BIOLOGY FINAL REVIEW

Mooradian 2015

Food Chain orFood Web?

# trophic levels? 4Tertiary Consumer? Bird, Toad or snake# trophic levels?Tertiary Consumers?

Pyramid of Energy:• Shows the energy available at each trophic level.

– The size of the blocks represents the proportion of energy

– Measured in Joules or Calories

Important Terms

• Producer/Autotroph (Auto = self, troph = feeder)– organisms that produce their own food directly from the sun’s

energy.• Take in energy from their surroundings and and store it in

complex molecules such as carbohydrates.• Use the process of photosynthesis to make complex

molecules

Important Terms

• Consumers/Heterotrophs (hetero = other)– Organisms that obtain energy by consuming other

organisms. Feed on others (hetero-troph)• Feed on producers and other consumers• Can be:

– Herbivores– Carnivores– Omnivores– Decomposers

Population PyramidsBE ABLE TO READ GRAPH:MALE vs FEMALE

BE ABLE TO COMPARE DIFFERENT AGE GROUPS

Draw 3 PYRAMID SHAPES FOR: RAPID, SLOW, NEGATIVE GROWTH

Eukaryotic Cells are Larger than Prokaryotic cells

Organisms that are Eukaryotic:Every organisms that isnot bacteria

– Animals– Plants– Fungus– Protists

Organisms that are Prokaryotic:

Every bacterial cell– Eubacteria– Archeabacteria

Eukaryotic vs. Prokaryotic Cells

Eukaryotic Cells

• Large• Have chromosomes• Have membrane-

bound organelles– Nucleus– Mitochondria– Centrioles

Prokaryotic Cells

• Small• No chromosomes,

only small circle of DNA (plasmid)

• No membrane-bound organelles.

Compare and Contrast…….

Animal

• No cell wall• No chloroplast• Small vacuoles• Has centrioles

Plant• Cell wall• Chloroplasts• Large vacuole• No centrioles

Compare and Contrast…

Please review the function of the following organelles/cell parts:

• Cell wall• Cell membrane• Nucleus• Mitochondria• Chloroplast• Vacuole

• Ribosomes• Golgi apparatus• Flagella• Lysosomes• Endoplasmic

Reticulum

PHOTOSYNTHESIS (chloroplasts)

6CO2 + 6H20 C6H12O6 + 6O2

reactants products Carbon dioxide + water glucose + oxygen

The Formula:

Cellular Respiration (mitochondria) – Releases the energy in food and turn it into a form that can be used for the activities of life.

The Formula:

C6H1206 + 602 6CO2 + 6H2O + 36 ATP

ORSugar (glucose) + oxygen carbon dioxide + water + energy

Identify products and reactants*Reactants ALWAYS to the LEFT of the Arrow

.

Passive vs Active Transport

• Diffusion

• Osmosis

• Facilitated Diffusion

• Pumps

• Endocytosis

• Exocytosis

Pictures of Passive and Active Transport

Using a Protein Pump

Using a Protein Channel

Energy Added

Which is Diffusion, Facilitated Diffusion, Active Transport?

Endocytosis and Exocytosis

http://www.northland.cc.mn.us/biology/Biology1111/animations/transport1.html

Terms:• Equilibrium – when 2 given areas have the same concentration

of molecules.

• Concentration Gradient – the difference in concentration of molecules in 2 given areas.

(Ocean- swimming with the tide or against it- which requires energy?)

• Defines HOW molecules will move, if going WITH the concentration gradient (from high to low = passive transport) or AGAINST it (from low to high = requires energy = active transport

There are 3 types of osmotic solutions

• Isotonic - equilibrium• Hypertonic – there is a greater concentration

of solute (ie, salt, the ‘stuff’) in the solution than in the cell

• Hypotonic – there is a greater concentration of solute (ie, salt, the ‘stuff’) in the cell then in the fluid around the cell

Comparison of Plant and Animal Cells in Osmotic Solutions

What is the major differences between what happens in plant and animal cells when placed in solution A? Explain

For A,B,C which column represents a cell in a Hypertonic, Hypotonic, Isotonic Solution?

For 1,2 –which row represents an Animal cell? A Plant cell?

A. B. C.

1.

2.

Properties of Water: Adhesion vs CohesionDefine Cohesion: • Molecules have a strong tendency to

‘stick’ to one another. Attraction between like substances

-Water is attracted to Water: spherical shape of the mid air droplet/ dome shape on the penny/in the petri dishDefine Adhesion: • Molecules have the ability to stick

(adhere) to one another. Attraction between different substances

-Water ‘sticks’ to other substances: teardrop shape at the tip of the pipette/penny/sides of the petri dish/sides of the capillary tubes

?

?

Which is greater……A or C?

Surface Tensionand

Capillary Action

Define Surface Tension: The property of the surface of a liquid (water) that allows it to resist an external force, (adhesion) due to the cohesive nature of the (water) molecules. Define Capillary Action: The movement of water (in a tube) due to the forces of adhesion, cohesion, and surface tension.

Biogeochemical Cycles• Water Cycle (hydrological)

– How water is transferred from the atmosphere to earth, through organisms and back to the atmosphere

• Carbon Cycle– How carbon dioxide and oxygen are cycled from the

atmosphere through organisms and back to the atmosphere.

• Nitrogen Cycle– How organisms convert (fix) unusable nitrogen in the

atmosphere to usable nitrogen to make proteins

Carbon Cycle

TERMS• Respiration• Photosynthesis• Combustion• Decomposition• Fossil Fuels

FOSSIL FUELS• Fossil fuels are made from organisms that died

millions of years ago and were buried• They are “non-renewable”, meaning there is a

limited supply.• Examples:

– Coal, oil and gas(fossil fuels)-nuclear power**sometimes ConsideredRenewable, but we WILL run out of uranium

1.

2.

3.

Renewable Resources

• Resources that have unlimited supply.• Often considered “green”• Often do not release harmful pollutants

and/or carbon dioxide• Examples:

– Wind, solar, geothermal, hydroelectric (water)

Acid Rain• Acid rain is formed when nitric and sulfuric acid is released into the atmosphere

from coal-burning power plants.• An increase in the acidity of an ecosystem

causes many organisms to die• Ecosystems downwind from factories experiencethe most acid rain

Causes?

Global Warming….Climate Change• When fossil fuels are burned to make energy,

they release CO2 and other harmful substances into the troposphere

• High levels of CO2 have been linked to increasing temperatures on Earth (Greenhouse Effect)

• Important greenhouse gases: CO2, H2O, CH4

• Increasing greenhouse gases on Earth contributes to climate changes (Global Warming)

Destroying the Ozone Layer• The ozone layer is the outer part of the stratosphere that protects us from carcinogenic (cancer causing) UV rays from the sun.Primary Cause:• CFCs (Chloroflourocarbons)– found in aerosol can

products and coolants attack and destroy ozone

Bacteria vs Viruses

STRUCTURE

Bacteria Viruses Larger than viruses (smaller than Eukaryotes)

10-100X smaller than bacteria

Single-celled prokaryotes

Single chromosome (plasmid-DNA), cell wall, cytoplasm, cell membrane, ribosomes

LIVINGCan be Autotrophs or HeterotrophsMOST are Heterotrophs: feed on dead animals/plants/wastes or are parasiticReproduce by Binary Fission

Non-cellular

DNA or RNA in the middle surrounded by a protein coat (spiky outer skin or ‘envelope’). No organelles, no cell wall

NONLIVING INTRACELLULAR- Can ONLY Live INSIDE cellsAre parasiticMost viruses target a specific organ or host cell.

Bacteria vs VirusesTreatment/Response to Antibiotics

Bacteria VirusesRESPOND to ANTIBIOTICS

Overuse of antibiotics has created ‘superbugs

DO NOT respond to ANTIBIOTICS

Very Hard to fight- can’t kill the virus without harming the host cell.

Virus causes an infection- we fight THAT with antibiotics.

Fight infections by hand washing, sanitation, cooking, washing food/refrigeration

VACCINES: Work on specific Bacteria or Viruses- stimulates the immune system.Made from weakened or killed forms of the bacteria or virus. The immune system then recognizes it and can fight it when you are infected with the stronger/live version.

Structure of DNA

• DNA is made up of nucleotides. Each nucleotide Each consists of:– A sugar “deoxyribose”– A phosphate – A nitrogenous base:

• Adenine Thymine• Cytosine Guanine

‘A’ binds with ‘T’, ‘C’ binds with ‘G’Hydrogen bonds

A bonds to C bonds to

Joined together by:

.

When nucleotides are bonded, they compose a DNA molecule

• Double-helix/spiral ladder• Sugar-phosphate “backbone”• Bases are rungs of ladder• Long sequences of bases make up genes

Number of Chromosomes

• Organisms have 2 different types of cells–Body (somatic) cells: skin, liver, brain–Sex cells (gametes): sperm and egg

• Because sperm and egg need to meet and combine their chromosomes to form a new individual, they have ½ the number of chromosomes as body cells

CHROMOSOME NUMBERS

sex cells/haploid (N) Body cells/diploid (2n)

• 23• 12• 4• 20• 10• 22

• 46• 24• 8• 40• 20• 44

In Humans Sex cells have 23 (23 from Sperm + 23 from Egg = 46)

Cells are formed by Mitosis and Meiosis• Mitosis is the division of a cell into body cells. (End with TWO daughter

cells, EACH with diploid # of chromosomes- 46 in humans)• Meiosis is the division of a cell into sex cells. (End with FOUR daughter

cells, EACH with HALF the # of chromosomes – haploid- 23 in humans)

Chromosomes are counted on karyotypes

Normal Human Karyotype:• 46 chromosomes

– 23 pairs• 44 autosomes

– 22 pairs• 2 sex chromosomes

– 1 pair• XX = female• XY = male

Down’s Syndrome Karyotype“Trisomomy 21”

**THREE Chromosomes at 21**

Genetics Terminology

• Genes – segment of DNA that codes for a trait

• Alleles – different versions of a gene:– Allele for brown eyes, allele for blue eyes

• Both genes code for hair color, but have different versions

• Letters are used to indicate alleles. Ex. B, b

Genetics Terminology, cont.• Dominant – The allele that is expressed (B)• Recessive – The allele that is not expressed when

paired with a dominant. Only expressed when paired with another recessive gene (b)

Ex) Heterozygous brown mouse (Bb) 1. How do you know brown is the dominant

phenotype? 2. How do you know to use the letter “B” or “b”

3. Homozygous Dominant = Recessive =

Genetics Terminology, cont.

• Homozygous – an individual who has the same alleles for a trait. (CC or cc)– Ex. 2 genes for cystic fibrosis

• Heterozygous – an individual who has different alleles for a trait. (Cc)– Ex. One gene for cystic fibrosis, one for normal

Genetics Terminology, cont.

• Phenotype: the physical traits of an organism– Ex: brown eyes

• Genotype: the genes that an individual has– Ex: Bb, BB = Brown eyes bb = Blue eyes

*The phenotype is determined by the genotype

Carriers• When discussing diseases, heterozygous individuals are

often called “Carriers” • Carries means that an individual carries a gene that is

not shown (expressed).• An “affected” individual has the disease in question. If

it is a recessive disease, their genotype will be homozygous recessive.

• Ex. People who are carriers for cystic fibrosis, have the gene for the disease, but do not have the disease (because it is recessive)

• Ex. Cross a normal individual (NN) with a person who is a carrier (Nn) for cystic fibrosis.– Normal is dominant (N)

Cross two carriers of Tay-Sachs disease

Phenotype:

_______ % Unaffected

_______ % Affected

Genotype:

________% Hom. Dom

________% Carrier (HET)

________% Hom Rec.

Generations• Parent generation = P• Offspring of P generation = F1• Offspring of F1 generation = F2

Cross a homozygous dominant purple flowerwith a homozygous recessive white flower. Givethe F1 genotype and phenotype percents.

Purple = PP, white = pp

Practice Crosses: *Review Genetic Disorder Packet

1. Cross Bb x Bb (black and white)2. Cross a heterozygous black mouse with a

white mouse. 3. Cross two carriers (Nn) for cystic fibrosis4. Cross a normal/unaffected hemophiliac with a

carrier (Sex-linked trait)5. Cross a normal/unaffected with a carrier for

tay-sachs (Autosomal trait)6. REVIEW DIHYBRID CROSS/FOIL METHOD

Phenotype:

_______ % ___________

_______ % ___________

Genotype:

________% Hom. Dom.

________% Het.

________% Hom. Rec.

Pedigree Charts• Pedigree charts follow a genetic mutation/disease

through several generations of a family.• You can determine what chance offspring has of

having a disease based on family history and Punnett Square.

• The main diseases that are tracked this way are:– Tay-sachs– Huntingtons– Colorblindness– Hemophilia– Cystic fibrosis

Basic Symbols

How to read a pedigreePHENOTYPESClear = unaffectedShaded = affectedGENOTYPESNot usually indicated,

but often can be determined by the phenotypes

Pedigree:recessivegeneticdisorder

RULES:1. An individual that is affected may have 2 unaffected parents

2. All of the children of two affected parents will have the trait.

Pedigree:DominantInheritance

RULES:1. Every affected individual has at least one affected parent2. Affected mating with unaffected have a 50% chance of passing the trait3. 2 affected individuals can have unaffected children

EVOLUTION BY MEANS OF NATURAL SELECTION

5 Principles

1. Variation• All species have variations• Variation is the raw material for natural selection

2. Struggle for Existence• Organisms produce more offspring than can survive.• The environment produces struggles organisms must surpass to survive

3. Only some survive to reproduce• Some are better able to survive and reproduce (pass on their genes)

4. Natural selection results in genetic change• Each generation contains an increased proportion of individuals with traits

that promote survival and reproduction.

5. Species adapt to their environment• Selection makes a population better suited to it’s environment.• The environment determines the direction of genetic change.

Evidence of Evolution

• Fossils– Bones, casts, footprints, amber, ice

• Homologous structures• Comparative embryology• Vestigial structures• Biochemical (DNA and amino acids)

Fossils

• Fossils are often found in sedimentary rock, which is formed from layers of silt and sand covering dead organisms.

• The oldest are found on the lowest layers, youngest in the upper layers

Homologous Structures(Comparative Anatomy)

Similar structure and anatomical position

(but not necessarily the same function) in

different organisms suggesting a common

ancestry or evolutionary origin

(e.g. wings of bats and arms of humans are homologous).

Vestigial Structuresstructures or organs that seem

to serve no useful function

Organisms having vestigial structures probably share a common ancestry with organisms in which the homologous

structure is functional

Types of Selection

The types of selection relate to the bell curve. The bell curve is altered due to forces of nature favoring certain traits over other.

Life On Earth• Earth formed approximately 4.6

billion years ago (bya)• Primitive Earth provided inorganic

precursors (methane, ammonia, water, etc.) from which organic molecules could have been made due to the presence of available free energy (lightening) and the absence of a significant quantity of oxygen.

• Chemical experiments have shown that it is possible to form complex organic molecules from inorganic molecules in the absence of life.

Bioethics and Uses of DNA:

• 1. DNA Fingerprinting• 2. PGD/PIGD (Embryo Screening)• 3. Genetic Testing- After Birth• 4. Reproductive Cloning/Stem cells• 5. Therapeutic Cloning/Stem cells• 6. Genetically Modified Foods

GMO DEBATE:

• Positive• Color/size • Add Nutritional value• Increase crop yield• Longer Shelf Life

Negative• Decrease Biodiversity• Farmers must buy new

seeds after a couple of seasons

• GMO labeling not done…

SOMATIC CELL NUCLEAR TRANSFER (SCNT)

Reproductive, Therapeutic CloningWHOLE ORGANISM ‘REPLACEMENT PARTS’

PROS CONS• Used for Organs, Skin

Grafts• No Organ Rejection• Allow people to clone

loved ones who have died

• Clones can act as organ donors for one another

• Replenish extinct or severely endangered species

• Use of certain Stem cells considered unethical

• Cloning humans is considered unethical

• Diminish individual uniqueness and self-identity

• Against law in many states• Loss of genetic variation• Cloning superior or

important historical figures is too closely related to the practice of eugenics (“playing god”)

Vocabulary to Know:• IVF = In Vitro Fertilization

• 1978 “in glass” “Test tube baby”• Reproductive vs Therapeutic Cloning

• Genetic duplicate vs “Replacement Parts”• Umbilical Cord Stem Cells vs Other Stem Cell Sources• PGD: Pre-implantation Genetic Diagnosis• Reprogenetics (IVF + PGD)

• Combining reproductive technologies (IVF) with Genetic Screening (PGD)