Prior knowledge · Web viewIt needs healthy and thick walls during pregnancy. When a female reaches sexual maturity and her body is able to become pregnant this cycle begins. If the

Name: ______________________________ Class: ___________

Year 8 Topic 2b: Inheritance and Evolution (Biology)

Contents Contents.........................................................................................................................2

Prior knowledge........................................................................................................3Characteristic and variation...........................................................................................4

Environmental variation..............................................................................................5

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Inherited variation.......................................................................................................5Investigating inherited traits in humans...................................................................6

How organisms inherit....................................................................................................7DNA, genes and chromosomes....................................................................................8Asexual reproduction: one parent ( ).................................................................10

Asexual reproduction in plants...............................................................................11Asexual reproduction in bacteria............................................................................12Investigating conditions for asexual reproduction of bacteria................................13

Sexual reproduction: two parents (+ ).........................................................15Sexual reproduction in plants.................................................................................16Investigating effect of shape on speed dispersal...................................................18Sexual reproduction in animals..............................................................................21Sexual reproduction in humans..............................................................................22Reproductive organs...............................................................................................22Puberty...................................................................................................................23Menstrual cycle.......................................................................................................24Investigating absorbency of sanitary pads.............................................................25Human pregnancy..................................................................................................27

Sexual reproduction and genetic variation...................................................................28Evolution......................................................................................................................31

Evolution by Natural Selection..................................................................................32Evolution by Artificial Selection (selective breeding).................................................35Species......................................................................................................................37Extinction...................................................................................................................37Classification.............................................................................................................40

Knowledge Organiser Questions...................................................................................44

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Prior knowledge 1. Which of these is an example of inherited variation within humans?

a) Hair length

b) Favourite colour c) Accent d) Eye colour e) Tattoos

2. A characteristic that is not expressed when a dominant one is present?a) Recessive b) Weaker c) Stronger d) Inherited e) Allele

3. Differences that can have any number value e.g. height, temperature, mass?a) Continuous b) Categoric c) Integer d) Discrete e) Infinite

4. The mnemonic that tells us all things that all living organisms do?a) 8 kg

cement

b) 4 Mr He

c) Rich Men Use X-rays in Vegas

d) Dear Katie Please Come Over For Great Snacks

e) Mrs Gren

5. What type of cell does not have a nucleus e.g. bacteria?a) Eukaryotes b) Gametes c) Nerve d) Prokaryotes e) Plant

6. A version of a gene?a) Allele b) DNA c) Chromoso

med) Nuclei e) Base

7. Number of pairs of chromosomes in a human nucleus?a) 46 b) 23 c) 4 d) 1064 e) 180

8. The type of reproduction that only requires one parent?a) Cloning b) Intercourse c) Sexual d) Asexual e) Plant

9. An individual that is genetically identical to another?a) Clone b) Twin c) Asexual d) Copy e) Inherited

10. Which of these cells is not a gamete?a) Pollen b) Plant egg

cellc) Embryo d) Sperm e) Human egg

cell11. The process of a male gamete and female gamete fusing together during sexual

reproduction?a) Sexual

intercourseb) Sex c) Fertilisation d) Ovulation e) Pollination

12. The animal male reproductive organ that produce sperm?a) Penis b) Testes c) Brain d) Scrotum e) Ovary

13. Two organisms that cannot breed together to produce fertile offspring are called different…a) Breeds b) Species c) Animals d) Creatures e) Types

14. An organism with two different alleles for a specific characteristic e.g. Bb?

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a) Homozygous

b) Clone c) Dominant d) Recessive e) Heterozygous

15. What is the first stage of evolution by both natural selection?a) There is

variation in a population

b) Humans prefer some traits

c) Some traits give advantage

d) Successful individuals live and breed more

e) Organisms choose to change

ReflectionBefore the topic End of the topic Score: /

15What were you pleased with? What were you pleased with?

Characteristics and variation Characteristics describe features: how something looks, behaves and works. The term ‘characteristics’ is very similar to the term ‘properties’ used in Chemistry.Some of the characteristics of this animal nerve cell are: It is 0.01mm wide and 2cm long It is long

for its size It is surrounded by a cell membrane It

has a nucleus It contains mitochondria It contains cytoplasm It is found in the nervous system of It contains

ribosomes animalsVariation describes differences between characteristics of individuals.The Simpson family are all human and share many characteristics with each other. There are clearly differences between them which we call variation. There are two reasons for variation between individuals: Environmental variation – caused by

differences in the way each individual lives Inherited variation– different instructions

passed down from parentsUsually the two reasons for variation can work together. For example, an individual may be born with the genetic code to be tall but may have been given a very poor diet growing up so would

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remain short. Other examples of characteristics that can be affected by both variations include IQ, sporting ability, literacy etc.

16. What is the scientific word that describes differences between characteristics of individuals?

17. What is the type of variation where differences are caused by different instructions being passed down from parents?

18. What is the type of variation where differences are caused by differences between the ways that individuals live?

19. Look at the plants below from the same species. Identify which of these factors are more likely to have been caused by environmental rather than inherited reasons.

20. Reviewing other prior key Biology knowledge: a) List 3 similarities between plant and animal cells?b) List 3 differences between plant and animal cells?

Environmental variation Environmental variation is caused by the environment in which an organism lives. These variations may be chosen or inflicted upon an individual.Some of the environmental characteristics of this person: Accent Hair length Ear piercing Tattoos Stomach sizeIt is relatively easy to affect some environmental characteristics of an individual.

21. Which of these differences between two sheep can be caused by environmental variation?a) Length of wool b) Breed c) Age d) Natural wool

coloure) Speed over

10mf) Size g) Horns h) Speed

Inherited variation All plants and animals have characteristics that are in some way similar to their parents’. These characteristics are passed down

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a. Number of leaves b. White potsc. Single stem d. Scratch on stalke. One leaf has been eaten f. Lack of waterg. Both are Poisonous h. Smelly flowers

from parent to offspring in genes. We will look at how these genes are passed down through generations later in this topic.Some inherited traits such as natural hair colour are easy to spot. Here are some examples of animal characteristics which are determined only by genes: eye colour blood group ear lobe or no ear lobe sex at birthIt is very difficult to affect the inherited characteristics of an individual.

22. Identify if each characteristic in humans is caused by inherited or environmental variation or a mixture of both.

a) Height b) Accent c) Natural hair colour

d) Natural skin colour

e) Ear piercing f) Speed g) Broken bones h) How fast you grow

i) Fashion sense j) Favourite colour k) Finger nail length

l) Number of teeth

m) Weight n) Blood group o) Favourite food p) Time to run 100m

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23. Complete the visual organiser below comparing environmental and inherited variation.

Investigating inherited traits in humans Continuous variables: Differences that can have any number value e.g. temperature

and height are called continuous. If both variables in an experiment are continuous then you can

plot a graph of your results. Continuous variables are caused by genes and environment.Categoric variables: Differences that can only have certain values such as words or

whole numbers only are called categoric. E.g. tongue roller or not a tongue roller.

A characteristic of any species with a limited number of values shows categoric data.

If the data that you record is categoric you can use a bar chart to display it.

Categoric variables are caused by genes only.24. Pick a characteristic to investigate and write a hypothesis to test.

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25. Is hair colour a categoric or continuous variable? Explain why?26. Is length of arm a categoric or continuous variable? Explain why?27. Write a conclusion for your investigation. How could you check that this

conclusion was valid for the whole school?

28. Complete MultiChoice Questions Topic 7.1a. List 5Qs you are happy with and 5Qs you are not.

29. What is wrong with this student’s explanation? Can you correct it?

How organisms inherit All organisms reproduce. It is one of the 7 life processes that all living things do:M – Move – move part or all of their body under their own powerR – Reproduce – have offspringS – Sensitive – experience thingsG – Grow – get larger with ageR – Respire – transfer energy from reaction between oxygen and glucoseE – Excrete – release waste productsN – Nutrition – gain vitamins and minerals neededAll organisms inherit characteristics from their parents through genes.

30. Which of these items/organisms perform all 7 life processes?a) A tree b) Bacteria c) A fox d) Grasse) Humans f) A piece of

paperg) A stone h) A virus

31. Which of the items/organisms above are alive and which are not? Why do you say this?

32. Silent Debate. You will work in a group of 3 or 4 people. Each needs a different coloured pen.

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In my class most people have gaps between their teeth and speak English. Therefore, most people in the World will have gaps between their teeth and speak English.Being able to speak English must be inherited as my parents and their friends all spoke English when they were young as well.

In primary school students are taught about Mrs Gren (or sometimes Mrs Nerg). It is important to remember that this is a mnemonic that reminds us of the things that all living things do. Viruses only reproduce and do not complete the other six process of Mrs Gren. This means viruses are not living.

Rules: #1 You must write on each other’s sheets #2 Write in clear English no text-speak or abbreviations. #3 Stay on topic. #4 You must be silent. You can only write your argument points down on this paper. #5 Use arrows to challenge specific points and write next to them.

Question to debate: DNA, genes and chromosomes

Every organism is made of cells. Within these cells are long lengths of DNA which contain all the instructions on how to make new cells. Plant and animal cells are called Eukaryotes and keep their DNA inside a nucleus.

Eukaryote comes from the Greek ‘eu’ meaning ‘true’ and ‘karyon’ meaning ‘nut’ or ‘kernel’. The word Eukaryote means ‘true-nut’ which relates to the nucleus.

Some organism such as bacteria are called Prokaryotes and do not have a nucleus, the do still store DNA in a nucleoid within the cytoplasm of the cell. Bacteria are examples of prokaryotic cells.

Prokaryote combines ‘pro’ meaning ‘before’ so means ‘before-nut’ relating to the lack of nucleus.

DNA is grouped into genes. Each gene provides the instructions for a certain chain of amino acids to be formed. These make proteins which are the units of the structure and function of the cell.Different forms of the same gene are called alleles. Different alleles are expressed in different ways e.g. there is an allele for hanging ear lobes and an allele for joined earlobes.Genes are then grouped into chromosomes. These chromosomes are stored inside the nucleus of eukaryotic cells.

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Considering the seven life processes, is a car alive?

33. What is the difference between prokaryotic cells (like bacteria) and eukaryotic cells (like plants and animals)?

34. What are genes made of?35. Where are chromosomes stored in a eukaryotic cell?36. How many pairs of chromosomes do humans have?37. What do we call a version of a gene e.g. hanging ear lobes?38. Which of the two types of variation do different genes cause?39. Match the term to the correct information.

Made of twisted chains of 4 complementary bases

Eukaryotic cells

Contains DNA but no nucleus Prokaryotic cellsDifferent versions of the same gene DNALong length of DNA containing different genes

Allele

Contains chromosomes inside a nucleus Chromosome

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40. Complete MultiChoice Questions Topic 7.1b. List 5Qs you are happy with and 5Qs you are not.

41. Extended writing challenge. You score points by using key words. You can use words more than once.There are 30-50 trillion bacteria inside the human body compared to 13-30 trillion human cells. Even though bacteria cells are much smaller, about 1-3kg of your mass is actually bacteria!Many of these bacteria live in our digestive system and are essential to helping us live.Use your knowledge of this topic to explain how bacteria and human cells are different and how they survive inside us.

1 Point: 7 life processes Respiration Food chain2 Point: Oxygen Diffusion3 Point: Eukaryotic cells Prokaryotic cells Mitochondria

Asexual reproduction: one parent ( ) In asexual reproduction there is only one parent from which the offspring receives genetic information. This means that the offspring will have the exact same genes as that parent.Having the same genes as each other means that offspring are genetically identical to each other and their parent. Organisms that are genetically identical are called clones.Clones can still experience environmental variation so do not have to look identical.

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The Human Genome Project (HGP) was the World’s largest collaborative biology project. The project set out to list the order of all the bases in DNA in a human being (there are only four types of bases in DNA but they can be used in any order). This activity is known as sequencing or mapping the human genome. The total length of the human genome is over 3 billion pairs long spread across the 23 pairs of chromosomes. Former US president Bill Clinton and former UK Prime Minister Tony Blair announced completion of the first draft of the human genome on June 26th 2000.

Scientists at the Welcome Trust Sanger Institute near Cambridge, UK remain at the fore of this human genome research.

The distinctive double helix shape of the DNA within chromosomes was discovered in 1953. James Watson, Francis Crick and Maurice Wilkins published the first paper

Organisms that reproduce using asexual reproduction: Single celled organisms: bacteria, fungi and malaria protists –

use asexual reproduction Plants: strawberries, dandelions, ferns, mosses Insects: there are some insects that can use asexual

reproduction if a suitable mate cannot be found. They include aphids, midges, bees, ants and grasshoppers

Animals: there have been examples of some female animals who have been unable to locate a male using asexual reproduction. They include: frogs, chickens and hammerhead sharks

Since all individuals are genetically identical in asexual reproduction the species can be very slow to adapt to changes in their ecosystem or expand into new ones.

42. What are the 7 life processes that all living things perform?43. How many parents are involved in asexual reproduction?44. What is a clone?45. Identical twins are clones or each other. Why do they not look identical when

they grow up?46. What is the difference between eukaryotic and prokaryotic cells?47. What are the two types of variation between individuals caused by?


49. Which of these are likely to be evidence of asexual reproduction?a) Offspring are identical

to each otherb) Offspring look

differentc) Offspring are all the

same aged) Offspring all display

the 7 life processese) Offspring are all same

speciesf) Only one offspring

50. Look at the KO Questions. Practice Look, Read, Cover, Write, Check for 5 minutes. Then work with your partner and test each other for another 5 minutes. Write a list of the 5Q numbers you are most confident with. Write another list with the 5Q you are least confident with.

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Asexual reproduction in plantsMany plants can reproduce asexually naturally or with human interference.Plants use asexual reproduction as an effective way of quickly colonising new space without needing to rely on the wind or pollinators.Gardeners use asexual reproduction of plants to produce large quantities of identical plants.

Asexual reproduction in plants: cuttings

Asexual reproduction in plants: runners

51. Why might a gardener want to clone their award-winning tomatoes?52. What do we call the genetically identical offspring of a plant that reproduces

asexually?

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Asexual reproduction in bacteria Bacteria can reproduce very quickly (some as quickly as once every 10 minutes). They use asexual reproduction as it is simpler and requires less energy. In bacteria we call this process binary fission.

They rely on mutations (mistakes in cell division) to create variation. Since they reproduce so quickly there are lots of opportunities for mutations to occur and the ones that are useful to be passed on.

It is this mutating nature that concerns humans at present as some bacteria are becoming resistant to anti-biotics which means we will not be able to kill them or cure illnesses they cause.

Bacteria can also transfer genes from one to another. This could potentially mean that if a harmless type of bacteria became antibiotic resistant, it could pass this gene on to a more dangerous type.

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The banana is one of the worlds most consumed fruit. Whilst there are many breeds of banana around 99% of the ones grown and eaten are a breed called the Cavendish. Unfortunately, a new fungus called Tropical race 4 (TR4) threatens the entire world’s supply.

This is not the first time a fungus has threated the banana industry. In the 1950’s a disease called Banana Wilt almost completely wiped out the most popular banana of the time, the Gros Michel.

Asexual reproduction and intensive farming both make the banana very

Asexual reproduction in bacteria

53. What is a mutation?54. What other types of organism can reproduce asexually?55. If you had a single bacterium, how many generations would be needed before

there were 32 bacteria?56. Bacteria are prokaryotic. What is the difference between prokaryotes and

eukaryotes?57. Why are antibiotic resistant bacteria so scary?

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Question to debate: Investigating conditions for asexual reproduction of bacteria

Bacteria prefer warm, damp places to reproduce. You are going to investigate which other conditions they prefer.

Use the following structure strip to plan your investigation.

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The World Health Organisation (WHO) state that antibiotic resistant bacteria pose one of the biggest threats to global health, food security, and development today.

It can affect anyone, of any age, in any country Misuse of antibiotics in humans and animals is accelerating

the process A growing number of bacteria are becoming harder to kill It is leading to longer hospital stays, higher treatment costs

and more deaths

There have been cases in the UK of people contracting illnesses that we can no longer cure due to the bacteria that cause them being resistant to antibiotics.

To prevent and control the spread of antibiotic resistant bacteria humans need to use less antibiotics. This poses an issue though as antibiotics are used to keep humans and farm animals

In order to reduce the use of antibiotics, should we ban their use for all animals except humans?

59. Hypothesis Different bacteria prefer different conditions to reproduce.60. Independent

variable (IV - you change)

61. Dependent variable (DV - you will measure)

62. 3 control variables (ensures only the IV affects the DV – makes it fair)Do not pick same measuring device (e.g. ruler)

1)

2)

3)

68. Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

5)

6)

80. Risk assessment(3 most obvious hazards in your experiment and how you will reduce their risk)

1)

2)

3)

86. Now test your hypothesis using the method. It will take at least 2 days before you will see the results.

87. Does your investigation support the hypothesis? How can you tell?18

Sexual reproduction: two parents ( + ) Sexual reproduction involves the mixing of genetic information from a male and female to make an offspring. The genetic information is transferred by sex cells known as gametes. The female gamete is known as the egg cell (ovum) and contains one of each pair of chromosomes (half the genes of the female parent).The male gametes are called sperm cells in animals and pollen cells in plants. They contain one of each pair of chromosomes (half the genes of the male parent).When the male and female gamete meet and combine genetic material it is called fertilisation.Each offspring is genetically different. This means that there is genetic variation between individuals.Misconception: It is important to be aware that sexual reproduction does not mean sexual intercourse. Sexual intercourse is a mechanism for delivering the male genetic information to the female egg cell.

88. How many parents are involved in sexual reproduction?89. Match the correct terms below

Female gamete Fertilisation Sperm

Male and female genetic information

combine

Male gamete (animal)

Egg

Male gamete (plant)

Pollen

90. What is wrong with this student’s explanation? Can you correct it?

91. If a normal human cell contains 23 pairs of chromosomes, how many does a sperm cell contain?

92. What is an allele?

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Sexual reproduction means having sexual intercourse. In humans a man’s penis makes sperm which can swim. One sperm then fertilises the egg and a baby is made. This new cell then grows really big until it looks like a baby. An adult cell is even bigger and is made from food.

93. What is the word equation for respiration?94. What is the difference between eukaryote and prokaryote cells?


Sexual reproduction in plants Many plants reproduce sexually using a process called pollination. Flowers are the sexual reproductive organs of the flower. They produce both the male gametes (pollen) and female gametes (eggs).

96. How many gametes can be made from a single normal cell?97. What are the male plant gametes called?98. What are the female plant gametes called?99. How much of the offspring’s genetic information comes from the male parent

and how much from the female parent during sexual reproduction?100. What is the main reproductive organ of a plant called?101. What is a clone?102. Which type of reproduction produces clones?103. Use the graphic organiser below to compare asexual and sexual reproduction in

strawberry plants.

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At the cellular level, the process of sexual reproduction in plants is identical to that in animals. The main differences occur in how the

pollen reaches the egg cell.

Some flowers rely on

pollinators (insects or animals) to move pollen from the anther (male structure) of the plant to the stigma (female structure). These flowers are generally brightly coloured, smelly and contain nectar to attract pollinators.

Other flowers rely on the wind to blow their pollen from their stamen (male structure) onto a stigma (female structure). Grasses and trees often use this pollination method.

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Hay fever (allergic rhinitis) affects more than 1million people every year. Sufferers are allergic to breathing in pollen from wind-pollinating flowers.

105. What is the main difference between sexual reproduction in plants and animals?106. What two methods do plants use to move the pollen to the egg during sexual

reproduction?107. What is the name of a plant’s male gametes?108. What is the name of a plant’s female gametes?109. What do pollinators do?110. What do we call a version of a gene?111. How much of the offspring’s genetic information comes from the male parent

and how much from the female parent during sexual reproduction?112. Which type of reproduction produces clones?113. Why might a gardener want to clone their award-winning tomatoes?114. What are genes made of?115. Where are chromosomes stored in a eukaryotic cell?116. How many pairs of chromosomes do humans have?117. What do we call a gene which causes a particular characteristic e.g. hanging ear

lobes?118. Which of the two types of variation do different genes cause?119. Match the term to the correct information.

Made of twisted chains of 4 complementary bases

Eukaryotic cells

Contains DNA but no nucleus Prokaryotic cellsDifferent versions of the same gene DNALong length of DNA containing genes AlleleContains chromosomes inside a nucleus Chromosome

120. Is hair colour a categoric or continuous variable? Explain why?121. Is length of arm categoric or continuous variable? Explain why?Investigating effect of shape on speed dispersal Plants compete for space. To avoid competing with their own offspring many plants have developed methods to disperse their seeds over a larger area:

Using animals – either seeds are carried on skin or through the digestive system e.g. sweetcorn

Using water – seeds are waterproof and float on water e.g. coconut Using expulsion – seed pods explode/pop and throw seeds e.g. poppy flowers Using wind – seeds are small and light and carried by wind – e.g. dandelion

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You are going to investigate what the best design for a wind dispersed seed might be.

We will consider these five different seed designs.

Hypothesis: the more blades a seed has the further it can be dispersed.

Use the following structure strip to plan your investigation.122. Hypothesi

sThe more blades a seed has the further it can be dispersed.

123. Independent variable (you change)

124. Dependent variable (you will measure)

125. 3 control variables (ensures only the IV affects the DV – makes it fair)Do not pick same measuring device (ruler)

1)

2)

3)

131. Step by step method (start each line with a command verb e.g.

1)

2)

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measure, set-up, record)

3)

4)

5)

6)

143. Risk assessment(3 most obvious hazards in your experiment and how you will reduce their risk)

1)

2)

3)

149. Now test your hypothesis using the method. Write your results in the table below.

Seed design – number of blades

Horizontal displacement (cm)1st test 2nd test 3rd test Average

1 blade

2 blades

3 blades

4 blades

5 blades150. Are there any anomalous results (ones that do not fit the pattern)? How can you

tell? If you have some put a circle around them.151. What sort of errors cause anomalous results? Tick the correct box

Random errors – ones we cannot predict Systematic errors – ones we can predict

152. What should we do with anomalous results?153. Calculate the mean average value for the horizontal displacement (cm)

Be careful to round your answer to 1dp using mean = (1st test + 2nd test + 3rd test) ÷ 3

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Remember to ignore anomalies e.g. If 2nd test result is anomalous then mean = (1st

test + 3rd test) ÷ 2154. Plot a bar chart of your results. It should look something like this when

complete.

155. Does your investigation support the hypothesis? How can you tell?156. What could you do to increase your confidence in your conclusion?Sexual reproduction in animals

Sexual reproduction is common amongst animals although some can also reproduce asexually as well. Most species of animal have a separate male and female parent although in some parents can change sex e.g. wrasses, clown fish, moray eels and gobies. In animals the female gamete is called the egg (or ovum) and is produced in the ovaries. The male gamete is called sperm and is produced in the testes.

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As with flowers, the main differences between animals in terms of their sexual reproduction is in how the sperm reaches the egg for example: External fertilisation: sperm and egg meet outside the bodies of

the parents. An example is in the spawning of many water living creatures such as fish and corals who lay their eggs and then the male swims over and drops sperm onto them.

Internal fertilisation: sperm is placed inside the female. The most common example is copulation (sexual intercourse for humans) where sperm are inserted using a penis and then swim to the egg.

157. What is the animal male gamete called?158. What is the animal female gamete called?159. In what habitat do animals that use external fertilisation tend to live?160. How is the sperm cell adapted to its role?161. How many gametes can a single normal cell make?162. How many chromosomes does a fertilised cell inherit from its female parent and

how many from the male parent?163. In a eukaryotic cell, where are the chromosomes stored?164. What are the 7 life processes?


166. Identify if each characteristic in humans is caused by inherited or environmental variation or a mixture of both.

a) Favourite food b) Accent c) Natural hair d) Natural skin colour26

coloure) Ear piercing f) Speed g) Broken bones h) Ability to tongue rolli) Fashion sense j) Tattoos k) Hanging ear lobes l) Number of teeth

167. Complete the visual organiser below comparing sexual reproduction in plants and animals.

Sexual reproduction in humans Human reproductive organs

In a female, the ovaries produce female gametes (egg cells) and make the female reproductive hormones oestrogen and progesterone.In a male, the testes produce male gametes (sperm cells) and make the male reproductive hormone testosterone.

Females are born with 200 000-400 000 eggs already in their ovaries. Over their life they may develop and release around 300-500 of these. After menopause, the ovaries stop releasing eggs and shrink.

Males produce sperm throughout their lives. Once released an individual sperm can only live a few days inside a female. Sperm are the smallest human cells by volume and although millions of them are released during each act of sexual intercourse, only one can fertilise the egg to make a new human.

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168. What are the male reproductive organs that produce sperm and testosterone called?

169. What are the female reproductive organs that produce eggs, oestrogen and progesterone called?

170. Where are human eggs produced?171. Where is the reproductive hormone testosterone produced?172. What are the two main female reproductive hormones called?173. What is wrong with this student’s explanation? Can you correct it.

Puberty The reproductive system of a child is not mature. It needs to change as a boy or girl develops into an adult, so that the system is fully working. The time when the changes happen is called puberty.Puberty happens for different people at different times. Many girls begin puberty between ages 8 and 14, with an average of 11. Girls develop more quickly than boys and most finish puberty within four years. Many boys begin puberty between ages 9 and 14, with an average of 12. Most boys finish puberty within six years.

The changes happen because of sex hormones produced by the testes in boys and by the ovaries in girls. These changes happen to both boys and girls during puberty:

underarm hair grows pubic hair grows body smell gets stronger emotional changes growth rate increasesGirls and boys grow at different rates as they mature. The time between puberty and adulthood is called adolescence.

Some changes happen only to boys or only to girls. They are:

Changes in boys: Changes in girls voice breaks (gets deeper) testes and penis get bigger testes start to produce

sperm cells shoulders get wider hair grows on face and

chest

breasts develop ovaries start to release egg

cells menstrual cycle starts hips get wider

174. What do we call the time when the human reproductive system matures?28

The testes are a female sexual reproductive organ. Eggs are made here and then sent into the female to make her pregnant. Testosterone is the male sex hormone which is made in the testes.

175. What chemicals cause puberty to begin?176. In general, do boys or girls tend to go through puberty first?

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177. Complete this comparison of the changes in boys and girls as they go through puberty

Menstrual cycle The menstrual cycle is a process where the female body prepares the uterus for pregnancy. The uterus (or womb) is the organ in which an unborn baby will develop during pregnancy. It needs healthy and thick walls during pregnancy.When a female reaches sexual maturity and her body is able to become pregnant this cycle begins. If the egg cell is not fertilised by a sperm cell then the cycle will continue again for another 28 days (approximately).

178. How long typically is the human menstrual cycle?

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179. For how many days typically during the menstrual cycle is the uterus lining breaking down?

180. What is the organ in which an unborn baby develops in a human?181. What are the two main female reproductive hormones?182. What are the female gametes called?183. Where are the female gametes made?184. What are the male reproductive organs that produce sperm called?185. Where is the male reproductive hormone testosterone made?186. What are the human male gametes called?187. Where are the male gametes made?188. Extended writing challenge. You score points by using key words. You can use

words more than once.Non-identical twins are formed from two different eggs and two different sperm.Identical twins are formed from the same egg and sperm that then splits in two after fertilisation.

1 Point Sperm Egg Ovary

In Roman mythology, Romulus and Remus were identical twin brothers who, after birth, were reared by a she-wolf. Romulus killed Remus and then went on to create Rome and the Roman Empire.Describe the story of Romulus and Remus before they were born.

2 Points Chromosomes Genes Gametes3 Points Fertilisation Pairs of chromosomes Uterus lining

Investigating absorbency of sanitary pads A sanitary pad is an absorbent pad worn by women to absorb menstrual blood during days 1-5 of the menstrual cycle. A tampon is a similar device that is worn inside the vagina.You are going to investigate the absorbency of two brands of sanitary pad.

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Brand of sanitary pad

Use the following structure strip to plan your investigation.189. Hypothesis All the brands of sanitary pads have the same absorbency.190. Independent

variable (you change)

191. Dependent variable (you will measure)

192. 3 control variables (ensures only the IV affects the DV – makes it fair)Do not pick same measuring device (ruler)

1)

2)

3)

198. Step by step method (start each line with a command verb e.g. measure, set-up, record)

1)

2)

3)

4)

5)

6)

210. Risk assessment(3 most obvious hazards in your

1)

32

experiment and how you will reduce their risk)

2)

3)

216. Now test your hypothesis using the method. Write your results in the table on the previous page.

217. Plot a bar chart of your results.218. Does your investigation support the hypothesis? How can you tell?219. What could you do now to increase your confidence that everyone agrees with

your answer? What would you hope to find discover?220. Why might we not believe the conclusions if one of the manufacturers of the

sanitary pads did the same experiment?When we want to test a result to see if it is reliable or not, we often use repeats. A result that is repeatable and reproducible is considered reliable.

221. If other people in your class got the same results as you using a different technique (e.g. how does mass of sanitary pad change) would that make your results repeatable or reproducible? Say why?

222. What type of reproduction forms clones?


Human pregnancy The time for which an unborn offspring develops before birth is known as the gestation period. The human gestation period is 40 weeks. During that time the number of cells in the baby increases from 1 to a few trillion (1 trillion = 1 000 000 000 000). This causes the baby to grow.

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RepeatableSimilar results

using same method

ReproducibleSimilar results using

different method

While the baby is growing inside its mother it is provided with nutrients via the umbilical cord and is kept safe inside the amniotic sac. The umbilical cord is connected to the baby’s belly button and the womb. Some harmful chemicals can pass through the umbilical cord which is why pregnant women must be more careful with their diet and health choices.

224. What is the length of the human gestation period?225. How do nutrients reach an unborn baby in the womb?226. Why is it so important that pregnant women must be careful what they eat and

drink?227. Elephants can live for up to 70 years in the wild. They have a gestation period of

around 95 weeks. How long after fertilisation would an adult female elephant give birth assuming a normal pregnancy?

Sexual reproduction and genetic variation Some characteristics are controlled by a single gene. Every human has two sets of genes for every characteristic. One from their male parent and one from their female. Each different version of a gene is called an allele.A characteristic an individual can be seen to have is called the phenotype e.g. blue eyes. The word ‘phenotype’ comes from a Greek verb meaning ‘to hit’ and the word ‘type’. Phenotype therefore means ‘to hit (or be) a certain type’.Since each offspring inherits two alleles for every characteristic there are three possible outcomes. One with the same pair of alleles and two with different alleles. These possible combinations are called the genotype (meaning ‘gene type’). Both inherited alleles are the same. We call this a homozygous

genotype34

Both inherited alleles are different. We call this a heterozygous genotype

The roots of these words can be seen in ancient Greek. ‘Homo’ means ‘same’ and ‘Hetero’ means ‘different’. The term zygous comes from zygote meaning ‘to yolk or join together’ and ‘ous’ meaning ‘having’. So homozygous translates to ‘having the same joined together’.

Where both inherited alleles are the same and the offspring has a homozygous genotype, it is easy to predict how the characteristic will be expressed.Where an offspring has a heterozygous genotype, we must consider which allele is dominant and which is recessive. The dominant allele’s phenotype will be the one expressed.Here is an example looking at Polydactyl (having more fingers or toes) The allele for the polydactyl phenotype is dominant over the

allele for being non-polydactyl phenotype. We use capital and lower-case letters to help show which allele

is dominant. Polydactyl = P. Non-polydactyl = p.There are 3 possible genotypes for a new offspring: PP – Homozygous dominant genotype. Offspring will be

polydactyl. pp – Homozygous recessive genotype. Offspring will be non-

polydactyl. Pp – Heterozygous genotype. Offspring will be polydactyl. and

will carry instructions for non-polydactyl which it may pass on when it reproduces.

228. What do we call a gene that is responsible for a different characteristic?229. What does ‘homo’ mean in Greek? What does ‘hetero’ mean?230. If a person inherits both a dominant and a recessive phenotype, which will be

expressed?231. If a person inherits two recessive alleles (they have a homozygous genotype)

which will be expressed?232. Which of these are phenotypes and which are genotypes?

a) an allele for red hair and brown hair

b) brown hair c) alleles for blue eyes and green eyes

d) allele for blue eyes e) tongue rolling allele f) gap teeth and no-gap teeth alleles

g) HH h) Hh i) Rr233. Which of these genotypes below are heterozygous, which are homozygous?35

a) genotype: Tt whereT = tongue rollt = no tongue roll

b) genotype: bb whereb = blue eyes

c) genotype: BB whereB = brown hair

d) genotype: Hh whereH = blonde hairh = red hair

e) genotype: Bb whereB = brown eyesb = blue eyes

f) genotype: Ff whereF = 10 fingers and thumbsf = more fingers

234. For each genotype above, consider which allele is dominant to predict which phenotype will be expressed?

235. What do we call a genotype where both alleles are the same?236. What do we call a genotype where both alleles are different?237. How do we show that one allele is dominant over another?238. How many alleles does each person have for each characteristic, even if they

only present one of them?


240. What plant did Gregor Mendel famously experiment with?241. Why did Mendel choose pea plants?242. What is the word equation for respiration?

Using Punnett Squares to predict offspring genotypesIf we know the genotypes of two parents it is possible to predict the genotype of their offspring. If we know which alleles are dominant and which are recessive we can then predict the chances of certain characteristics being expressed. This is straight forward if the parents are homozygous with the same phenotype e.g. both parents have two alleles for blue eyes. The offspring will have blue eyes. It is more difficult when considering parents who either have different phenotypes or who are heterozygous. In this case we use Punnett squares. Here is an example showing the 4 stages of filling it in

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In the 1800s Gregor Johann Mendel, the son of an Austrian farmer carried out some inheritance experiments using pea plants.

Pea plants were chosen as they were easy to grow, had many offspring and had varieties in genotype and phenotype which were easy to observe such as pea size and flower colour.

He discovered that inheritance of traits followed a pattern and that the characteristics of offspring could be predicted. He became known as the ‘father

In this example both the mother and father are heterozygous for the tongue rolling allele. The ability to roll your tongue is dominant over not being able to. Both parents would be able to roll their tongues.

The 4 squares to the bottom right corner show the possible genotypes a child may inherit of these two parents are TT, Tt, Tt or tt. It is most likely (3 in 4 chance or 75%) that any offspring would be able to roll their tongue.

243. Complete the following Punnet square for a homozygous male and a heterozygous female.

Blonde hair = HRed hair = h

Female genotype Hh

244. What colour hair would each parent have?

245. What colour hair would each offspring have?

246. What are the chances of any offspring having Red hair?

247. How many offspring have a heterozygous genotype?

H h

Mal

e ge

noty

pe H

H H

H

248. Complete the following Punnet square for a heterozygous male and a homozygous female.

No gap between teeth = G

Gap between teeth = g

Female genotype gg

249. What gap would each parent have?

250. What gap would each offspring have?

Ma le

ge not

yp e Gg

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251. What are the chances of any offspring having a gap?


253. Which of these genotypes below are heterozygous, which are homozygous?g) Genotype: Tt where

T = Tongue rollt = No tongue roll

h) Genotype: bb whereb = Blue eyes

i) Genotype: BB whereB = Brown hair

j) Genotype: Hh whereH = blonde hairh = red hair

k) Genotype: Bb whereB = Brown eyesb = Blue eyes

l) Genotype: Ff whereF = 10 fingers and thumbsf = more fingers

254. For each genotype above, consider which allele is dominant to predict which phenotype will be expressed?

Evolution Evolution is gradual change in the inherited characteristics of a population over time and many, many generations leading to the production of new species. It has led to the huge variety of different living things on our planet.

As people began noticing more and more similarities between living things they started to wonder if they were related. The similarities between these unborn offspring is quite apparent.

The idea of evolution gained further evidence and support with the discovery of: Fossils – the remains of organisms from hundreds of thousands

of years ago Genetics and inherited variation The evolution of antibiotic-resistant strains of bacteriaWe can show how closely organisms are related using an evolutionary tree like this:

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255. What is evolution?256. Does evolution happen quickly?

Misconception: When people talk about evolution and the fact that humans evolved from apes some imagine it happened quickly and that once upon time, an ape gave birth to a human. This is not the case. The process took an incredibly long time with tiny changes, occurring each generation. The primates from which we evolved millions of years ago are long now-extinct.

257. Which species are our closest living relatives?258. Other than visual similarities, what three pieces of evidence are there for

evolution?259. What are the 7 life processes?260. What is the word equation for respiration?


Evolution by Natural Selection Charles Darwin first

explained his Theory of Evolution by Natural Selection in his book ‘On the Origin of Species’ in 1859. It is often also referred to as 'Survival of the Fittest’.

Darwin’s theory can be broken into 5 separate stages:39

1. Within a population there is variation – individuals are different2. Some traits are advantageous for survival3. Individuals with the advantageous characteristics survive and

breed more4. More offspring are born with the advantageous traits5. Over many generations the entire population end up with the

advantageous traitsFor organisms to evolve they need variation. This is easier with sexual reproduction. The quicker they reproduce, the more time around the stages they can go and the quicker they can evolve.

262. Why can it be more difficult for organisms that produce clones to evolve?263. Bacteria reproduce far quicker than humans. What does this mean in terms of

how quickly they can evolve?264. What is the successful phenotype shown in the giraffe evolution pictures above?265. Use bits from this example to explain how polar bears evolved to have white fur.

266. Human ancestors walked on all fours. Standing upright allowed us to see over long grass. Explain the evolutionary steps that led to all humans walking upright.

267. How can science ideas evolve? Do they fit the 5 steps?

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Example answer for how a cactus evolved to have spikes1. There was variation in cactus leaves. Some leaves were spikier than

others2. Spikier leaves were an advantage as they protected against

herbivores3. Plants with spikier leaves survived and bred4. More offspring with spiky leaves were born5. Eventually over many generations all cacti had spikes

An earlier theory for why living things evolved was put forward by Jean-Baptiste Lamarck. He suggested that organisms passed on desires for certain traits as a consequence of desires they had in their life. Using his theory adult giraffes would have really wanted longer necks as they competed for food so would have strengthened their necks. As a consequence of this they

would have passed on this desire for long necks to their offspring who would have been born with slightly longer necks.

Investigating evolutionary pressuresYou will investigate how a variation in beak shape can drive evolution by natural selection.

Beak shape

1st generation 2nd generation 3rd generation 4th generation

Popu

latio

n

Food

Offsp

ring

New

popu

latio

nFo

od

Offsp

ring

New

popu

latio

nFo

od

Offsp

ring

New

popu

latio

nFo

od

Offsp

ring

Toothpick 1Chopstick 1

Forceps 1

Spatula 1268. Predict what will happen to this species of creature eventually assuming the

type of food does not change?269. If we were to change the food type to spaghetti how might this affect the

investigation?270. This investigation uses a model to represent the beaks of birds. Complete this

pros and cons dial for the model. Add an arrow to show your final opinion on how useful the model is.

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271. What are the 7 life processes?272. Complete the following Punnet square for a heterozygous male and a

heterozygous female.Brown hair = BBlonde hair = b

Female genotype Bb

273. What colour hair would each parent have?

274. What colour would each offspring have?

275. What are the chances of any offspring having Brown hair?


Mal

e ge

noty

pe B

b

277. What is the difference between prokaryotic cells and eukaryotic cells?278. Which famous scientist wrote the Theory of Evolution by Natural Selection?

Artificial Selection (selective breeding) Artificial selection or selective breeding has been used by humans for thousands of years. It has allowed us to produce: Food crops from wild plants Domesticated animals from wild onesIt is the process by which humans breed plants and animals with desirable qualities such as fast growing, affectionate or with lots of milk.The stages of selective breeding are the similar as those for natural selection except this time humans decide which traits are best and which parents to breed1. Within a population there is variation –

individuals are different2. Some traits are advantageous to humans

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3. Individuals with the advantageous traits are bred together4. More offspring are born with the advantageous traits5. Over many generations the entire population end up with the

advantageous traitsIn the period 1957 – 2005 humans have been able to use selective breeding to increase the mass of chickens by over 400%. Over a longer period, humans have also been able to dramatically increase the size of corn cobs.

279. Use this example to explain how jersey cows were selectively bred to produce

so much milk.

280. Lap dogs are breeds that are small and relaxed. Describe the steps that have led to them being selectively bred to be this way.

281. Use the graphic organiser below to compare evolution by natural and artificial selection.

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Example answer for how carrots were selectively bred to be orange rather than purple

1. There was variation in carrot colours. Some were less purple and more orange

2. People thought the orange carrots were prettier3. Farmers bred the orange plants together4. More offspring with orange roots were born5. Eventually over many generations all carrots have orange roots

282. Extended writing challenge. You score points by using key words. You can use words more than once.

One of the observations made from the discovery of our ancestors’ fossils is that our brain capacity has grown.

Explain how sexual reproduction may have led to this evolutionary change to have happened

1 Point Sexual

reproduction Variation DNA2 Points Generations Reproduce Gametes3 Point Alleles Chromosomes Eukaryote

283. Label this animal cell and match the name of each component to its role. Controls what enters and

leaves cell Nucleus

Protein synthesis Cell

membrane

Controls the cell Cytoplasm

Performs respiration Mitochondria

Fluid that fills the cell Ribosome44

The wolf in our home. Over thousands of years humans have selective bred dogs until we have ended with the many breeds we have today. All these dogs have the same wolf ancestors. Originally, the friendliest individuals were bred together to produce offspring who were more likely to protect us than eat us. Since this time, we have selectively bred dogs to be tall or short, fast or slow, spotty and a whole range of other characteristics.

Species Eventually two groups of organisms from the same original population become very different due to natural selection. When they can no longer produce fertile offspring (offspring that can reproduce) they are called a new species. Humans and Chimpanzees are different species as are Cats and Dogs or Tigers and Lions. Some of these species can breed together but their offspring are not-fertile so cannot reproduce again. Another word for not-fertile is infertile.Organisms that look very different from others but are still able to produce fertile offspring are from the same species but are considered to be a different breed. For example, a poodle and a Labrador look very different but can breed together.

284. What does fertile offspring mean?285. The table below shows some different offspring and information about their

parents. In each case describe if the parents were the same species or not.a) Mule – not fertile

Results of breeding a male donkey and female horse

b) Cockapoo – fertileResults of breeding a cocker spaniel and poodle

c) Zebroid – infertileResults of breeding a male zebra and female horse

d) Liger – unable to have offspringResults of breeding a male lion and female tiger

e) Mule sheep – fertileCross between a Blue-faced Leicester male and a Mountain female

f) Centaur – imaginaryResults of human imagination. Part horse part human.

Extinction When the last individual of a species dies and there are no more left we say that species has become extinct.Species of organisms go extinct when their ecosystem changes and they are not able to adapt or evolve quickly enough to cope. The main causes of extinctions are: Predation (and hunting) – a new predator joins the ecosystem Competition – a new more successful competitor species joins

the ecosystem Disease - a new disease spreads throughout the species

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New species are often caused because of changes in the habitat in which an organism lives. This process of a new species being created is called speciation. Examples of changes that lead to speciation include separating groups of individuals and competition for food sources. Darwin famously

Habitat loss – they no longer have a place to live Climate change – drastic changes that the species cannot adapt

toIn each case above, humans can easily cause extinctions either deliberately or through unintended action.

286. What are the 5 causes of extinction?287. Which of the 5 causes of extinction do you think is having the greatest impact

on wildlife now? Why do you say this?288. Consider each species below. For each give the main reason it is

endangered/extinct.a) Western Lowland

Gorilla (Gorilla gorilla)Suffered a population decline of more than 60% since the early 1980s. Hunting and deaths caused by Ebola were the main causes of this decline and both these threats continue to affect the Western Lowland Gorilla population.

b) Sumatran Orangutan (Pongo abelii)Has suffered a population decline of more than 80% over the last 75 years. The species is seriously threatened by logging (both legal and illegal), conversion of forest to agricultural land, and oil palm plantations, and fragmentation by roads.

c) The Polar Bear(Ursus maritimus)Classed as Vulnerable. Recent modelling of the trends for sea ice extent, thickness and timing of coverage predicts dramatic reductions in sea ice coverage over the next 50 to 100 years due to global climate change. It is suspected that there will be a population reduction of at least 30% over the next 45 years as a result of this habitat loss and declining habitat quality

d) Cyanea superba is listed as Extinct in the Wild. This tree was endemic to the island of O'ahu in the Hawaiian Islands. There were around 60 plants in the 1970s, the species then declined to only five plants and these too have finally gone. The causes of the wild population’s extinction were

e) Maui Hesperomannia (Hesperomannia arbuscula)Is a small shrubby tree known only from the Hawaiian Islands of Maui and Oahu. There has been an observed population decline of 25-50% over the last three years and the number of known individuals is less than 25. Main threat is because of

f) Telestes polylepis is a Critically Endangered freshwater fish, known only from a very small stream (1 m wide and 2 km long) in Stanicka Jaruga, Croatia. Ongoing habitat degradation caused by water extraction and the presence of introduced trout species threatens the survival of this fish

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competition with alien plants, habitat degradation by feral pigs, slugs and wildfire

competition with alien plant species.

289. Silent Debate. You will work in a group of 3 or 4 people. Each needs a different coloured pen.Rules: #1 You must write on each other’s sheets #2 Write in clear English no text-speak or abbreviations. #3 Stay on topic. #4 You must be silent. You can only write your argument points down on paper. #5 Use arrows to challenge specific points and write next to them.

Question to debate:



The 5 mass extinctions of Earth

In the history of the Earth, there have been 5 mass-extinctions Each marks the end of a period of Earth’s history. Each was caused by a dramatic environmental change.

Current theories are that these events cause the mass extinctions:

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Should we try and prevent organisms going extinct? What about dinosaurs, should we try and bring them back?

Ordovician - An ice-age which dramatically decreased temperatures

Devonian – A huge algae bloom resulted in a lack of oxygen in the oceans

Permian – volcanic activity or meteor strikes caused dust which blocked the sunlight and cooled the Earth rapidly

Triassic – rising sea levels due to a greenhouse effect caused by carbon dioxide and methane released following volcanoes

Cretaceous – a huge meteor strike caused dust which blocked the sunlight stopping photosynthesis and cooling the Earth

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Classification We can sort organisms into groups according to their characteristics.

One method of sorting all living things was developed by Carl Linnaeus and then more recently added to by Carl Woese. They sort things into:

A mnemonic to help remember: Dear Katie Please Come Over For Great SnacksThree Domains: 1. Bacteria - prokaryotes (cells without a nucleus) 2. Archea – ancient prokaryotes3. Eukaryotes – all plants, animals, fungi and protists (cells with a

nucleus)Then Six Kingdoms: The Two prokaryotes, Plants, Fungi, Protists and Animals.The Latin name for living things has their Genus and their Species. For instance, humans belong to the Genus Homo and the species Sapiens so we are Homo Sapiens.

292. What are the three domains in the Linnaeus classification method?293. What is the mnemonic we use to remember the Linnaeus classification order?

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294. What are the six Kingdoms in the Linnaeus classification? Which are the four that have eukaryotic cells?

295. The Latin name for the Bald Eagle is ‘Haliaeetus leucocephalus’. What genus does it belong to? What species does it belong to?

296. The English Oak tree belongs to the genus Quercus and the species robur. What is its full Latin name?

297. Label this eukaryote (plant) cell.

Nucleus Cell wallCell

membrane Chloroplast

Cytoplasm Vacuole

Mitochondria Ribosome

298. Label this eukaryote (animal) cell and match the name of each component to its role.

Controls what enters and leaves cell Nucleus

Protein synthesis Cell membrane

Controls the cell Cytoplasm

Performs respiration Mitochondria

Fluid that fills the cell Ribosome Latin names for some common animals and plants

Homo sapiens - Human Loxodonta africana – African Elephant

Rattus rattus – Black Rat Panthera leo – Lion

Felis domesticus – Domestic Cat

Rhinoceros unicornis – Rhinoceros

Oryctolagus cuniculus – Rabbit

Canis lupus – Wolf

Bovidae ovis - Sheep Equus quagga – Zebra

Canis lupus familiaris – Dog Gorilla gorilla - Gorilla

Equus caballus - Horse Vulpes vulpes – Fox

Malus pumila - Apple Musa paradisicum - Banana

Cucumis sativas - Cucumber Citrus Limonium – Lemon

Citrus aurantium – Orange Lactuca sativa - Lettuce

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299. Lions (Panthera leo) are one species of animal. Read the statements in the table. Some are right and some are wrong.

Tick one box for each statement.

I am sure this is right

I think this is right

I think this is wrong

I am sure this is wrong

a) The members of a species have many characteristics in common.

b) All the members of a species live together in the same place.

c) Members of the same species can breed to make fertile offspring.

d) Members of different species cannot breed to make fertile offspring.

e) The characteristics of a species stay the same forever.

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This is the classification key you will remember doing in Primary School. It looks at:1. Domain Eukaryotes 2. Kingdom Animals3. Phylum: Animals usually fall into one of five different phylum

which are Cnidaria (invertebrates), Chordata (vertebrates), Arthropods, Molluscs and Echinoderms.

4. Class: Vertebrates are sorted into five classes which are amphibians, birds, fish, mammals, reptiles.

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300. What does vertebrate mean? Where in the human body are the vertebrae?301. Describe two differences between reptiles and amphibians.

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Question to debate: 303. Animals can be classified into groups called classes. The diagram shows some

classes of animals.

How do you feel about the statements in the table below? Use the diagram to help you decide.

Tick one box for each statement.I am sure this is right

I think this is right

I think this is wrong

I am sure this is wrong

a) All animals are vertebrates.b) All reptiles are vertebrates.c) All insects are invertebrates.d) Jellyfish are a type of fish.e) Some birds are mammals.f) Fish have more features in

common with birds than they do with starfish.

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What class does a duck billed platypus belong to? It lives in water, lays eggs, has fur, poisonous spur, feeds its young with milk and has a beak.

Knowledge Organiser Questions KQ.1. The differences between characteristics of

individuals?Variation

KQ.2. Variation caused by differences in the way that individuals live?

Environmental variation

KQ.3. Differences that can have any number value e.g. temperature and height?

Continuous

KQ.4. Differences that can only have certain values e.g. are words or whole numbers only?

Categoric

KQ.5. Cells that keep their DNA inside a nucleus? EukaryotesKQ.6. Cells that do not have a nucleus for their DNA e.g.

Bacteria?Prokaryotes

KQ.7. Long lengths of protein that contain all the instructions on how to make new cells?

DNA (Deoxyribonucleic acid)

KQ.8. A small length of DNA that controls whole or part of a characteristic

Gene (or allele)

KQ.9. A long length of DNA containing different genes. Humans have 23 pairs of these?

Chromosomes

KQ.10. Reproduction requiring only one parent. Produces clones?

Asexual reproduction

KQ.11. An individual that is genetically identical to another?

Clone

KQ.12. The variable we change in an investigation? IndependentKQ.13. The variable we measure in an investigation? DependentKQ.14. Variables that we keep the same so that only

the independent variable affects the dependent variable?

Control

KQ.15. Reproduction where genetic information from a male and female are mixed to make an offspring?

Sexual

KQ.16. The name for male and female sex cells? GametesKQ.17. Female gametes are called? EggsKQ.18. The process of male and female gametes

meeting and transferring genetic informationFertilisation

KQ.19. Human male gametes produced in the testes?

Sperm

KQ.20. Plant male gametes released by flowers? PollenKQ.21. A result that does not fit the pattern? Anomalous (or anomaly)KQ.22. Errors we cannot predict? Random errorsKQ.23. Errors or mistakes we can predict e.g. zero

error?Systematic errors

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KQ.24. The female reproductive organs that produce eggs, oestrogen and progesterone?

Ovaries

KQ.25. The male reproductive organs that produce sperm and testosterone?

Testes

KQ.26. Where eggs are produced and released by human females?

Ovaries

KQ.27. Where sperm are produced by human males? TestesKQ.28. The time when the human reproductive

system matures?Puberty

KQ.29. The two main female human reproductive hormones?

Oestrogen and progesterone

KQ.30. The main male human reproductive hormone?

Testosterone

KQ.31. The length of the average human menstrual cycle?

28 days

KQ.32. The organ in which an unborn baby develops before birth?

Uterus (or womb)

KQ.33. During sexual reproduction, every offspring inherits two sets of these one from each parent?

Chromosomes

KQ.34. An experiment that gets the same results using the same method?

Repeatable

KQ.35. An experiment that gets the same results using a different method?

Reproducible

KQ.36. An organism with two identical alleles for a characteristic?

Homozygous genotype

KQ.37. An organism with two different alleles for a characteristic?

Heterozygous genotype

KQ.38. A characteristic an individual can be seen to have e.g. blue eyes, brown hair?

Phenotype

KQ.39. Each different version of a gene for a certain characteristic?

Allele

KQ.40. The allele which will be expressed when an offspring has a heterozygous genotype

Dominant

KQ.41. The name for an allele which is not expressed when a more dominant allele is present?

Recessive

KQ.42. Chance of an offspring having a homozygous dominant genotype when both parents have heterozygous genotypes?

¼ or 25% or 1 in 4

KQ.43. Chance of an offspring having a homozygous dominant genotype when both parents have homozygous dominant genotypes?

1 or 100% or 4 in 4

KQ.44. The gradual change in the inherited characteristics of a population over time and many,

Evolution

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many generations?KQ.45. Another name for Darwin’s Theory of

Evolution which is sometimes known as survival of the fittest?

Natural Selection

KQ.46. In artificial selection (selective breeding) who chooses which individuals should breed together?

Humans

KQ.47. Why can bacteria evolve more quickly than humans?

Reproduce more quickly

KQ.48. Two organisms that are so different they cannot breed together to produce fertile offspring are said to be from different…

Species

KQ.49. The mnemonic to help remember how we classify all living organisms?

Dear Katie Please Come Over For Great Snacks

KQ.50. This group of animals have backbones and are from Eukaryote domain and the Animal Kingdom.

Vertebrates

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Documents

Prior knowledge · Web viewIt needs healthy and thick walls during pregnancy. When a female reaches sexual maturity and her body is able to become pregnant this cycle begins. If the