THE SCIENCE OF ZOOLOGY
I. What is Zoology?
A. Zoology is the study of _________________________________________
B. Zoology is a
science guided by two central principles
1.
2.
C. Characteristics of the study of zoology
1. Principles of genetics and evolution guide
much zoological study.
2. Principles learned from one animal group can
be applied to others.
3. We use the scientific method to conduct solid
research.
II. How do we define life?
A. This would seem
to be a simple thing, but it actually isn’t.
1. Many of
the characteristics of life can be found in nonliving things.
2. We
could define life on the basis of ___________________________
__________________________________________________________.
3. This
would exclude non-life, but also early
forms from which cellular life
descended.
a. Properties
exhibited by life today are different from those at its
origin.
b. Evolution (change
over time) has generated many unique living
properties.
B. We can describe the general properties of
living things.
1. ________________________________________
a. Living organisms are
made up of far more complex molecules
than nonliving matter.
b. These complex molecules are called _____________________
and include…
1) _____________________,
which in turn are made up of
chains of amino acids
2) _____________________,
which are chains of simple
sugars
3) _____________________,
which include DNA and RNA
4) _____________________,
which include triglycerides and
cholesterol
c. These macromolecules are common to all living things.
1) That means that the general structure of
macromolecules
evolved early.
d. These basic
building blocks of life, macromolecules, also
provide a potential for diversity.
2. Complexity and Hierarchical Organization
a. Life has an ascending order of complexity…
1) Macromolecules organize to become
2) _____________________ which organize
to become
3) _____________________ which organize to
become
4) _____________________ which organize
to become
5) _____________________ which organize
to become
6) _____________________ which organize
to become
7) Populations which organize to become
8) Species.
|
Ascending
complexity |
Example |
Explanation |
|
Cell |
|
Heart muscle cells |
|
Tissue |
|
The muscle tissue of your heart |
|
Organ |
|
The heart is composed of muscle, connective,
nervous, and epithelial tissues |
|
Organ system |
|
The heart and all the blood vessels |
|
Organism |
|
A human is made up of 11 organ systems
|
b. Each level has unique
abilities and requirements
1) Cells can replicate but are not independent in an
organism.
c. New characteristics
that appear at the next level of organization
are __________________________________________.
1) As we go through our survey of the animal
kingdom, we
will see animal life becoming ever more complex.
d. Emergent properties at higher levels are a result of
evolution.
1) e.g. We wouldn’t
expect animals without hearing to
develop vocal
communication.
3. __________________________________________
a. Genes replicate genes
b. Cells divide to produce new cells
c. Organisms produce new organisms
d. Reproduction can occur sexually or asexually
b. Reproduction is
not necessary of individuals, but if a species is
to survive, some members of the species must reproduce.
4. Possession of a __________________________________________
a. Genetic information in animals is contained in DNA.
b. DNA tells a cell
what to do, when to do it, & how to do it.
5. _____________________
– all the chemical reactions within a cell
a. Living organisms maintain themselves
by obtaining nutrients
from the
environment.
b. Breakdown of nutrients provides both
energy and molecular
components
for cells.
c. Most metabolic pathways occur in
specific cell organelles.
6. _____________________
describes characteristic changes an
organism undergoes from origin to adult.
a.
It involves changes in size and shape, and differentiation within
the organism.
b.
Some animals have uniquely different embryonic, juvenile and
adult forms.
1) The transformation from stage to stage is
_____________________.
2) e.g. Think of frogs. They
go from egg to aquatic larvae (a
tailed, gilled tadpole)
to a tailess, lung breathing adult.
7. Environmental
Interaction
a. _____________________ is
the study of an organism's
interaction
with the environment.
b. Organisms respond to stimuli in the
environment, a property
called _____________________.
c. We cannot separate life and its evolutionary lineage
from its
environment.
III. Zoology as a Part of Biology
A. Characteristics of
Animals
1. Animals are a
branch of the evolutionary tree of life.
2. Animals are _____________________
(their cells contain nuclei)
3. Animals are unique
in their nutrition.
a. They eat other organisms and therefore need to capture
food.
4. How are they different
from plants?
a. Animals lack _____________________ & do not have rigid
_____________________.
5. How are they different from fungi?
a. Animals lack the absorptive _____________________ of fungi.
IV. Principles of Science
A. Nature of Science
1. Science is a way
of asking about the natural world to obtain precise
answers.
2. Science is
separate from activities such as art and religion.
a. Science is guided
by _____________________.
b. Science has to be
explanatory by reference to natural law.
c. Science is _____________________
against the observable
world.
d. Science
conclusions are tentative; they are not necessarily the
final word.
e. Science is _____________________.
B. Scientific Method
1. Criteria for
science form a hypothetico-deductive method.
2. _____________________
are based on prior observations of nature or
derived from theories based on nature.
3. Testable _____________________
are made based on hypotheses.
4. _____________________ are conducted to
see if the hypothesis
explained the phenomenon we were interested in.
5. A hypothesis
powerful in explaining a wide variety of related
phenomena becomes a _____________________.
6. The
most useful theories explain the largest array of different natural
phenomena.
V. Theories of Evolution and Heredity
A. Darwin’s Theory of
Evolution
1. Evolution –
a. We can talk about this change as a
change in characteristics.
b. We can also talk about this as a
change in allele frequencies in
a population (we will
revisit this idea in lab).
2. Ernst Mayr describes five central theories of “Darwinism.”
a. __________________________________________
1) We do see how related species, across
generations,
have changed.
2) This fact is documented in the fossil record.
3) e.g. the horse lineage
b. __________________________________________
1) We can see that organisms that share common
characteristics often also share a common ancestor.
2) This is the simplest explanation for shared
characteristics.
3) e.g. We know when
we’re looking at a bird. They have
feathers, forelimbs modified as wings, a horny beak,
etc.
a) Some common ancestor had these
characteristics.
b) From this ancestor, birds diversified and
filled the
many niches we find them in today.
4) This idea of branching lineages forming a
phylogeny is
confirmed by expanding research on morphological and
molecular similarities.
c. __________________________________________
1) If some members of a species get isolated
(perhaps on
an island) they will continue to evolve (become better
suited
to their particular environment) in isolation.
2) Over time, differences between the two groups
will
accumulate to the point that the two groups will no longer
interbreed.
3) From one original species, we now have two.
d. __________________________________________
1)
oceans of time in which natural selection occurs.
2) Small incremental changes, over long periods
of time,
cause gradual evolution.
3) There are some researchers who have found
evidence
that some evolutionary changes do not occur gradually.
e. __________________________________________– the
driving force of
1)
Members of a population show natural variation.
2)
Some variations are beneficial to survival.
a) Those with beneficial traits will be more
successful
i) They will obtain
more food
ii) They will obtain better living space
iii) They will attract more desirable mates
b) Because they are more successful, they will
be
more
successful at raising offspring.
i) They will have
more resources to devote to
ensuring
the survival of their young.
3)
Offspring resemble their parents
a) The offspring of better adapted parents will
inherit
successful
traits from their parents, and likewise have
greater
success in reproduction.
4)
Individuals with less favored traits will be less successful
and leave
behind fewer offspring.
5)
Over time, the species as a whole will become better
adapted to
their environment due to…
a) Differential _____________________
b) Differential _____________________
2. There was only one
fly in the ointment. Why do offspring
resemble their
parents?
a.
b. He assumed the current theory of blending inheritance was
correct
3. This problem was resolved when Mendel’s
theory of particulate
inheritance became well known in the very early 1900s.
3.
Darwinism.”
B. Mendelian
Heredity and the Chromosomal Theory of Inheritance
1. Chromosomal
inheritance is the foundation for genetics and evolution.
2. Mendel developed particulate inheritance from
working with garden
peas. He
discovered…
a. If you cross a purple-flowered and
white-flowered plant, you do
not get a
blended light purple plant.
1) The plants were not passing on traits that
were mixed
together
in their offspring.
2) This refuted blending inheritance.
3) We now know that we pass on traits to our
offspring as
“particles” that are
called _____________________, carried
on _____________________.
4) Recessive traits are masked by dominant
traits.
3. Since Mendel’s work, scientists have
continued to learn about heredity.
4. Improvements in microscopes allowed
observation of sperm and the
location of the _____________________ line (eggs and
sperm).
5. We have discovered that body cells have
chromosome pairs (one from
your mother and one from your father), but germ cells
only a single set of
chromosomes.
a.
e.g. In humans, normal body cells have 46 (23 pairs) of
chromosomes. Eggs or sperm only have 23 chromosomes.
6. These discoveries have clarified the mode of
heredity.