The Study of Life The concepts and principles that allow people
to understand the natural environment form the core of Biology,
which is basically the study of life. One of the most basic aspects
of Biology is that living things do not live in isolation. There is
a direct link in all living things that help support the entire
planet. These things supply life to other organisms, medicine,
symbiotic relationships, etc. How does the study of life have
relevance to people? Does study of life need to include the study
of non living things? If so, how?
Slide 3
Interactions of Life There is order in the natural world. God
has designed living things to interact with each other to from a
natural environment that supports itself and His creation as well
as providing a way for life to thrive on Earth. Since the
beginning, God has expected man to be good Stewarts of the Earth.
Biologists term this relationship as the web of life. Please
indicate how human beings fit into this web and some of our
responsibilities in maintaining a healthy web, along with this list
the benefits of studying Biology. Energy is the ability to cause
change and all organisms get their energy from food.
Slide 4
Characteristics of Living Things Distinguishing between a
living thing and a non-living thing can be tricky at times. There
are non-living things that seem to have life but do not fit the
description, or parameters of living things. In order to be
considered an organism, the thing must have all of the following
characteristics. 1. Have an orderly structure. 2. Produce
offspring. 3. Grow and develop. 4. Adjust to changes in the
environment.
Slide 5
Determining living from Non-Living Consider the mildew that can
be found on the rotten fruit we used to attract the fruit flies.
Examine the structure under a microscope (teacher will set up).
Note: If you have allergies of any type have a fellow student
describe to you what they are seeing. Do not touch the slide. Write
an hypothesis about rather this is living or non- living. Examine
the slide again in a couple of days and write what changes you have
seen. Turn in with revised hypothesis, data, and what you inferred.
Research if you were correct and submit a paper with results
including the references.
Slide 6
Stimulus and Response/Environment Some of the abiotic factors
that make up an environment are air, water, weather, temperature.
Organisms (living things) within an area, have the capability of
responding to the environment and the abiotic factors present in
that environment. These organisms respond to their environment in
many ways. A tree may change its color and shape in weather. A fox
may pounce on a rabbit when hungry. In turn, a rabbit may run for
cover when it rains. Any response to a stimulus is normal and to be
expected in the natural world. The internal responses are
adaptations that God has placed in the organism.
Slide 7
Homeostasis and Adaptation All living things have a quality
they possess that can respond to internal and external stimulus in
order to survive and be able to reproduce. This adjustment is known
as homeostasis, and is the process of internal feedback. In order
to reproduce and live, organisms use energy which causes change.
The inherited structure, behaviors, and internal processes are able
to respond to environmental factors. These responses are known as
adaptations. Give an example of a species, and a stimulus that
would cause the species to adjust and respond to the stimulus
(adaptation). Remember the rolly polly?
Slide 8
Scientific Methods The gathering of information and attempts to
systematically answer questions is known as scientific methods.
Consider science as being an investigator, not unlike a detective
you see on television. An investigator can see a problem, or have a
question. He or she will then set out in a systematic way to answer
those questions and find the correct answer. The following slides
will explain the process of being a scientific investigator and
then you will investigate a question.
Slide 9
Steps of the Investigator Hypothesis. Is an explanation for a
question or a problem that can be formally tested. In order to form
a hypothesis the investigator (scientist) must be able to test it.
A hypothesis is NOT a guess. The investigator must be able to
consider a question, use previous knowledge, data, or research to
form a reasonable thought as to the answer of the question. He or
she must also be willing to accept that the hypothesis may not be
correct and may need to adjust the answer or answers. Otherwise
there is a built in bias (or tendency to follow down a wrong path
to come up with a preconceived idea). The investigator must be sure
that he or she does not allow for a bias to influence the testing,
results, or interpretation of data. In short, keep an open mind
young minds.
Slide 10
The Investigator and Experiments
Slide 11
A Controlled Experiment Experiments break down into two groups.
The control group and the experimental group. If you are testing
something like a plant, the control is the conditions similar to
all plants, like they would all have soil, same water, etc. The
experimental group would be a set of plants that had fertilizer
(but not all plants would have fertilizer). Then, you would collect
data by quantitative (measurements) and qualitative (observations),
and make inferences from that data which supports (either confirms,
rejects, or is inconclusive to your hypothesis).
Slide 12
How to Design an Experiment The designing of an experiment is
only limited to the depth of your imagination and creativity. Also,
researching other experiments and consulting with others can help
you design a unique and challenging experiment. In a controlled
experiment, only one condition can be changed at a time, because
you must be able to determine which factor is influencing any
changes you are seeing. If you try to test a hypothesis with more
then one condition (in the experimental group) then you will not be
able to determine which condition causes the data, or changes that
you may observe.
Slide 13
Independent Variable The condition in an experiment that is
tested is the independent variable (this condition takes place in
the experimental group). In other words, its the item that is not
consistent with both groups. There is also the chance that there
will be no difference in the experimental group as opposed to the
controlled group. This would result in an inference that
independent variable being tested is having no affect on the group.
Either way you have data and can make an inference.
Slide 14
Dependent Variable Say you are testing a group of plants and
you have a change that is observed or measured in the experimental
group. This change, or condition would be known as the dependent
variable. Think of the fruit flies and come up with a set of
variables that are the same for all, then add a variable that is
different from the other 2 communities. Explain what the
independent variable would be and what the dependent variable would
be. In some experiments it may be impossible to apply controls
without affecting the natural environment. Under these
circumstances the person conducting the experiment would need to do
an observational experiment which would rely on making direct
observations without interfering with what is occurring in the
natural settings. You see these types of studies when Biologists
study species in their natural environment. An example would be the
study of elephants. The Biologist would watch their behavior, make
notations on what theyre seeing and then try to make some sort of
inference based on what they see in the behavior and what responses
they may note.
Slide 15
Data and Safety
Slide 16
Chapter 2 The study of plants, animals, what they eat, where
they grow and live; and what they eat or what eats them is called
natural history. So, the branch of Biology that developed from
natural history is known as ecology. Ecology is the study of
interactions that take place between organisms and their
environment. Most ecologists use descriptive and quantitative
research. That is, descriptive is what they observe and
quantitative is what they can measure.
Slide 17
Continued When you think of the biosphere, think on a large
scale like in comparison to the galaxy and beyond (Toy Story, quote
from the famous Buzz Light-year.) Then, think of all the life that
is supported from the bottom of the ocean to the top of our
atmosphere. Biotic Factors are all the living organisms that
inhabit an environment. Remember that an environment is simply the
surroundings of organisms that are in interaction with each other.
For example, this classroom is considered an environment. Of course
there are factors contained within an environment such as weather,
temperature, other organisms, and non living factors, these are
known as abiotic factors. Abiotic factors. Do you know what abiotic
means? And, do you understand the importance of abiotic factors on
living organisms?
Slide 18
Terms
Slide 19
continued A habitat is simply the place where an organism lives
out its life. It could be a stream, a field, or a rotten log, but
its home. Habitats can be lost due to human neglect or natural
factors such as floods, etc. So, what is the difference between a
habitat and an ecosystem? How about a niche? What is it? How do we
define it? And why does it matter? A Niche is all the strategies
and adaptations that a species uses to live out its life. It
includes all of the interactions of Abiotic factors and Biotic
factors in its environment. Try to think of it as the history of a
species in a particular area. Who its friends are, what its
adaptations are, where it lives, how it thrives, etc.
Slide 20
Symbiosis Most species survive because of their relationship
with other species. It does not always have to be that there is
competition between species at all times. In fact, most of the time
the role of one species helps another for their mutual existence.
When there is a relationship with a permanent and close association
between species, it is known as symbiosis. Remember when we led
each other around with one person with closed eyes and the other
helping them to walk? That was an example to help your remember
this concept. There are basically 3 types of symbiotic
relationships that follow.
Slide 21
Symbiotic Relationships Continued Mutualism. Both species
benefit from their relationship. Mutual means to share so they are
sharing something to both benefit. A lady bug on a rose. The lady
bug eats a fungus that would kill the rose so the lady bug gets fed
and the rose gets protected. Commensalism. One species benefits and
the other is neither harmed nor benefitted by the relationship.
Consider moss at the base of a tree. The tree doesnt benefit nor is
it harmed by the moss, but the moss benefits from the habitat
supplied by the tree. Shade, etc. Parasitism. One species benefits
and the other is harmed. Imagine if a tick gets on your head. The
tick is living off of you, and is a carrier of say rocky mountain
fever. You are then harmed by this illness (no bueno).
Slide 22
Producers and Consumers The ultimate source of energy for all
life on Earth is the sun. Organisms that use light energy or energy
stored in chemical compounds to make energy rich compounds is known
as a Producer (Autotroph). Examples would be plants, fruits, etc.
An organism that feeds on other organisms in order to get its food
(energy) is known as a consumer (heterotrophs). An example of this
would be a Bison (Remember George????). Organism that are Consumers
can be broken down into 3 subcategories. A. Herbivore-only eats
plants. B. Carnivores-eats other animals. Note: Some animals do not
kill other animals, but they eat those animals which are dead or
dying, these are known as scavengers. C. Omnivore-Us humans, we eat
everything! Plants and Animals. Bacteria and fungi break down
complex compounds of dead and decaying plants and animals these are
called Decomposers.
Slide 23
Food Chain Energy is said to flow through an ecosystem and
never really decrease. It is looked at as converted into heat or
reabsorbed and reused, etc. But, our main thought is to know the
basic principal of a food chain. An example is berries being eaten
by a dear, who is then eaten by a black bear. The berries are on
the lowest form of this chain, the next level is the deer, and then
the bear. Interestingly, anything left behind by the bear will be
taken up by the Decomposers and thus starting the cycle again.
These levels of the food chain are known as trophic levels.
Slide 24
Chapter 3 Limiting factors are those things that affect an
organisms ability to survive in its environment, such as the
availability of water, food, predators, etc. A limiting factor is
any abiotic (non living) or biotic (living) factors that influence
an environment of an organism. Lets use the mouse as an example. A
lack of cover (abiotic) affects the mouse and his or her
opportunity to avoid the Hawk (biotic) that would swoop down and
scoop him or her up as a meal. Range of Tolerance is the ability of
an organism to withstand fluctuations in biotic and abiotic
factors. A population will survive according to its tolerance for
environmental extremes, and of course its tolerance for biotic
factors increasing or decreasing dependant upon the type of
symbiotic relationship.
Slide 25
Continued The natural changes that occur over time, or species
replacement is known as succession. Succession takes place over
time. Some organisms may move into an area, some may die out, etc.
These changes will affect the ecosystem, or that area that supports
the biological community. There are 2 types of succession: 1.
Primary Succession is an area where the land was barren of
organisms. At some point, when conditions are proper, the first
species to take hold in an area takes hold. These species are known
as pioneer species and are usually the smallest of organisms. Think
back to the example of a food chain and how small organisms attract
bigger organisms. 2. Secondary Succession is an area that has
already built up but is wiped out by an event, such as fire. The
species can survive or at least have microorganisms that will
survive and grow and eventually repopulate. Think of some of the
burn areas that have come back. The fire represented change but not
total devastation. It may look totally devastated but there is
still organisms within soil, etc. that will come back. A climax
community is a community that has reached a stable point where it
undergoes very little change.
Slide 26
Biomes A biome is a large group of ecosystems that have a bunch
of grouped and stable communities within them. They are subdivided
into 2 different types. Terrestrial biome (land & Air) and
Aquatic biome (seas, lakes, ponds, etc.) Approximately 75% of the
Earth is covered with water. These biomes are separated into groups
such marine biomes (saltwater) and freshwater biomes. The portion
of the aquatic biomes that can receive light (shallow enough for it
to penetrate) is known as the photic zone which is important for
life within those waters, much the same way that sun is important
for life on terrestrial biomes.
Slide 27
Chapter 4 A population is a group of species that all live in
the same area. Our fruit flies were considered a population. The
growth of populations generally start off slowly and then grows
faster as the organisms grow and the group has more organisms that
can reproduce. At some point the growth begins to grow
exponentially and if you were to graph to populations growth you
would have a J shaped curve. Populations do have growth limits and
these limits are availability of food, predators, disease, and lack
of space. When this happens the J shaped curve stabilizes as the
populations approaches its carrying capacity. Carrying capacity is
the number of organisms that an environment can support
indefinitely.
Slide 28
CHAPTER 4 CONTINUED There are 2 categorys for reproduction
patters of species. They are as follows: 1. Rapid life pattern.
These are organisms that tend to multiply very quickly, are small
in size, and then have a short life. Some examples of these are
mosquitos, flies, etc. 2. A slow life pattern. These organisms tend
to multiply slower, have less species born at a time, are larger in
size and live much longer. Examples are humans, elephants,
etc.
Slide 29
Carrying Capacity Remember that carrying capacity is what an
environment can hold in terms of population. Remember there will be
numerous species within an environment but the population is the
key here. How many organisms can be sustained. Recall that in an
environment too many predators, or too few predators can have an
impact in terms of limiting factors and growth. But, once the
population reaches a certain limit it cannot be sustained because
other factors such as availability of food, disease, etc. will come
into play.
Slide 30
Fluctuations When carrying capacity is reached, the population
will fluctuate because of limiting factors. At times the population
will exceed capacity, then die or disperse and then fall below
capacity due to these issues.
Slide 31
Dispersal Organisms disperse through an environment in 3
different ways, which are: 1. Random it just happens. It could be
the wind blowing seeds in a certain way, or a fox carrying seeds in
his digestion system to plant them where he relieves himself. 2.
Uniform is due to room. A group of trees for example needs a
certain space to grow, so they will grow but in a uniform
appearance. The limitation here is tied into available space for
them. 3. Clumped, is a form of dispersal of a source usually
brought about by either food needs, or safety. Mushrooms will clump
in the ideal growing space for them, or newborn animals will clump
together for warmth and protection.
Slide 32
Density Factors There are 2 types of limiting factors related
to dispersal. They are density dependent factors and density
independent factors. Density Dependent factors are directly related
to the population of an area. The heavier the population the more
likely that limiting factors will affect the area in a bigger way.
These limiting factors are disease and parasites will increase
their effect; competition for resources like hiding spots, food,
room to grow etc. Density Independent factors can affect an area
regardless of population. These are things like floods, pollution,
drought, temperature, volcanic eruptions, etc. NOTE: These factors
tend to be Abiotic factors.
Slide 33
Predation In a balanced ecosystem there is a proper balance
between predator and prey, or species that affect that environment.
But, imagine if you introduced a bunch of coyotes to an area that
has few rabbits. The coyotes would soon decimate that population of
rabbits and that would also harm those organisms that depend on the
rabbits for their survival. In a properly balanced system there is
enough birth and continuance of prey to support the predator and
keep things moving along in blissful harmony. But, tamper with it
too much and things will certainly change for the worse. This is
why hunting is carefully monitored for the good of an area.
Slide 34
Competition and Overcrowding Interestingly, overcrowding has
been studied and found to be a limiting factor. Although not
completely understood, studies have shown that when overcrowding
exists. If we had kept the fruit flies longer we probably would
have noticed this effect. However, individual animals have shown
patterns of increased aggression, decrease in parental care,
decrease in fertility and resistance to disease under circumstances
of crowding. Does this happen in humans?
Slide 35
Demography Demography is the study of human population size,
density, birth rates, death, and movement over time. What
significance do you think this type of study has for mankind?
Slide 36
Growth Rate Growth rate is simply adding the births and
immigration rate together and then subtracting the deaths and
emigration (people leaving). This will result in either a positive
growth rate, negative growth rate, or rarely no growth.
Slide 37
Chapter 5 Biological Diversity (Biodiversity) refers to the
variety, or different types, of species located within an area. For
instance, you would have more types of species in a rain forest
then you would in a corn field. The larger the number of species
within an area the greater the Biodiversity. Remember the
importance of symbiotic relationships amongst species, if an
organism is lost, it will affect other organisms.
Slide 38
Loss of Biodiversity Extinction is the loss of a species to the
last one, where they are lost forever and will never return again.
Endangered species are those that are at risk of becoming extinct.
There are numerous types of sea turtles that fit this definition
and need to be protected. Protection programs are designed to save
these species from extinction. For instance, in Hawaii its against
the law to touch a sea turtle while snorkeling or scuba diving.
Threatened species are those that are in danger of becoming
endangered and need conservation efforts as well.
Slide 39
Threats to Biodiversity Habitat loss is one of the biggest
reasons for decline in biodiversity. The Amazon rain forests, and
the coral reefs are examples. Habitat fragmentation is the
separation of wilderness areas from other areas. Building of roads
and other man made things cause most of the fragmentation. This
causes problems due to increased risk of fire, changes in local
climate, increased disruption of ecological processes, and new
opportunities for invasions by introduced species, which are also
known as exotic species. An edge effect is where 2 different types
of ecosystems come together. For instance, a new housing
development against a forest would change that edge effect,
possibly introduce new species, and possibly disrupt the species
that have been displaced or that live deeper in the forest.
Slide 40
Pollution Habitat degradation is simply the damage to a habitat
by pollution. There are three types of pollution that exist. Air
pollution is brought about by particles being put into the air by
man made processes such as manufacturing, etc. Occasionally,
however, abiotic factors such as large fires come into play and
pollute the air. This type of pollution is much easier on the
environment however because there is a natural cleansing process
such as winds, rains, etc that can more readily remove fire
pollutants. Land pollution is largely brought about by garbage. We
consume and then we have waste and there is an on going need to
balance and be innovative in managing this type of pollution. Water
pollution is brought about when contamination is brought into any
water source. It could be intentional dumping of wastes, or just
the washing off of pesticides by rain into water systems. Whatever
the cause, this affect can be devastating on aquatic biomes.
Slide 41
Chapter 6 NOTE: Add pages to slides covering 6, 7, 8. Elements
are substances that cannot be broken down into simpler chemical
substances. For instance, water is not an element because it can be
broken down into hydrogen and oxygen. The four most abundant
elements in the body are carbon, hydrogen, oxygen, and nitrogen.
These naturally occurring elements make up about 96% of the mass of
a human body. Question: How can that be? How can these elements
make up such a large portion of the body? Reference page 141.
Slide 42
Trace Elements and Atoms Some elements such as iron and copper
are present in living things in very small portions. These small
amounts are called trace elements. Trace elements are absorbed into
plants through the root system and transferred to animals, or
people. Trace elements aid in cellular metabolism, so although they
are found in small quantity they are vital to cell function and
life. Rather elements are found in living or non living things, the
smallest particle of the element is an atom. Atoms are the basic
building blocks of all elements. Page 142
Slide 43
Structure of Atoms The center of atoms is called the nucleus.
All nuclei are positively charged because of the presence of
protons. The different elements have different numbers of protons.
Electrons, which are negatively charged, circle the nucleus. There
are shells that circle the nucleus in rings. The first cell can
hold a maximum of 2 electrons, the 2 nd layer can hold 8, and the 3
rd can hold a maximum of 18. 143
Slide 44
Compound and covalent bonds A compound is simply 2 different
elements that combine. For example, when sodium and chloride
combine you have table salt. Elements combine when they are going
to be more stable. This simply means that the outer shell reaches
its maximum. There are 2 ways in which atoms bond. One is they
share electrons (covalent bond) and the other is to gain or lose
electrons (ionic bond). Page 147
Slide 45
Chemical Reactions In organisms, chemical reactions occur
within cells. Thats why we live and die one cell at a time.
(Rapidly of course!). All of these chemical reactions are known as
the organisms metabolism. We are constantly breaking down
substances, rebuilding new substances, using nutrients, getting rid
of wastes, etc. Page 147
Slide 46
Chapter 7 Read pages 171-176 in your text for these points: The
cell theory is made up of 3 main ideas. Pg. 172 1. All organisms
are composed of one or more cells. 2. The cell is the basic unit of
structure and organization of organisms. 3. All cells come from
preexisting cells. By duplication and forming identical cells. All
cells contain specialized structures called organelles. These break
down into 2 distinct types of cells. Those that do not have
membrane bound organelles called prokaryotes (example would be most
bacteria). And, those cells that do have membrane bound organelles,
which are known as eukaryotes. Most, but not all, eukaryotes are
multicellular organisms the exception would be some algae and
yeast, as well as amoebas.
Slide 47
Maintaining a Balance in Cells Your cells need nutrients such
as glucose, amino acids, and lipids to function. It is the job of
the plasma membrane to allow, or not allow, these into the cell.
Plasma membrane play an important role in cellular homeostasis by
allowing certain nutrients in, and letting waste out. One such
mechanism is selective permeability. Think of a screen in your home
that lets fresh air in, and keeps big nasty mosquitoes from getting
in and getting you.
Slide 48
Chapter 8 Read pages 195 through 200. Although cells have a
semi permeable membrane (in most cases), water moves freely into
and out of cells to reach a balance. This movement is called
Osmosis. It is simply water trying to reach a balance, between
whats inside the cell and whats outside (extracellular). Isotonic
solution the concentration of dissolved substances in the solution
is the same as the concentration of dissolved substances inside the
cell.
Slide 49
Chapter 8 Continued Hypotonic solution is the concentration of
dissolved substances is lower in the solution outside the cell then
the concentration inside the cell. Remember hypo means below, so a
hypotonic solution means the solution has less dissolved particles
in it then what is inside the cell. Hypertonic is the concentration
of dissolved substances outside the cell is higher then the
concentration inside the cell. Look at and discuss figure 8.2-8.4
page 197.
Slide 50
Continued When cells move across a membrane requiring no energy
the movement is called passive movement. Passive movement can occur
when a particle is transported by proteins. Transport protein help
substances move through the plasma membrane. The protein is
attached to the cell membrane and provides a bridge of sorts for
certain material to pass through and into the cell. This type of
passive movement is called facilitated diffusion. These channels
allow specific molecules to flow through. In facilitated diffusion
by carrier protein the movement is with the concentration gradient
and requires no energy input from the cell.
Slide 51
Active Transport A cell can move from particles of a lower
concentration to a region of higher concentration, but it must
expend energy to counteract the force of diffusion (like swimming
against a current). Movement of materials through a membrane
against a concentration gradient is called active transport and
requires energy from the cell. In active transport a transport
protein called a carrier protein first binds with a particle then
it carries it into the cell through a portal (or door) of a cell
and then releasing them. The cell uses energy to take in the
particle, and energy is used in picking up, binding, and carrying
the particle into the cell. There is also communication within the
cell, kind of like a door man that lets the cell know its OK to let
the particle inside.
Slide 52
Transport of Large Particles Endocytosis is a process by which
a cell surrounds and takes in material from its environment. The
material does not pass directly into the cell membrane, it is
engulfed and enclosed and eventually absorbed into the cell.
Exocytosis is the expulsion (or getting rid of) materials from a
cell. This is how the cell expels wastes. Cells also use this
method to secrete hormones. Both of these processes use energy and
move masses of material.
Slide 53
TO-DO This is an assignment! Starting 11/29 period 1 will
review 5 slides per day as homework. When class starts you will sit
down in your learning groups for 20 minutes and review the slides
you did the previous night as homework. You will use your
electronic gadgets, but once this time period is over you will put
them away and keep them OFF. Starting 11/30 period 6 will review 5
slides per day as homework. When you come to class break up in your
groups and review those slides as group study using your gadgets to
enhance learning for 30 minutes. Once this is over all gadgets are
OFF and put away. NOTE: If anyone is not working on their slides as
I monitor you, you will be broken up to study alone and will
receive NO participation points for this exercise. Participation
points will only be issue when you stay in your group, stay in your
seats, stay on track, and keep the noise volume down to inside
voices. This will help you prepare for the final in 2 weeks.