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Transcript
Biology 11
Elgin Park Secondary
2016/2017
Name: _______________________ Block: ___
Teacher: _____________________ Room: _____
Biology 11
Teacher: Ms. Trevelyan
Website : mrstrevelyan.com
Office hours: Mondays, Wednesdays after school
E-mail: [email protected]
Room : 243C
Welcome to Biology 11! Over the next few months, you are going to explore a world of science
you’ve probably never experienced before!
BIG IDEAS:
Characteristics of Living
Things
All living things have common
characteristics
Process of Evolution
Living things evolve over
time.
Taxonomy
Organisms are grouped on the
basis of identifiable similarities.
Materials Covered
1. Scientific Method
2. Evolution
3. Taxonomy
4. Cells
5. Viruses
6. Bacteria
7. Plants
8. Animals
EVALUATION
Tests and Quizzes
Assignments, labs
Final Exam
45%
30%
25%
TOTAL
100%
CLASS EXPECTATIONS
1. Students are expected to arrive to class on time and be seated before the bell rings. If
you are late, please wait outside the door until the teacher comes and lets you into the
class.
2. Students are expected to attend class on a regular basis. If you miss a class for any
reason, it is your responsibility to talk with your teacher on the day of your return to
school so that you can collect missed work. If you miss a test, please bring a note signed
by your parents/guardian explaining the reason for your absence.
a. Late work with a valid excuse will be accepted for full marks
b. Late work without a valid excuse that is handed in after the assignment has been
marked and returned to students will be given a maximum of 50% of the mark.
2
3. Be respectful of your fellow students and your teacher. When someone is speaking, pay
attention. Do not use cell phones or other electronic devices during lecture time or group
work.
4. Please be aware that cheating and/or plagiarism will result in a mark of zero being
assigned to all students involved. This includes sharing test questions/answers with
other students who have not yet written the test, copying homework or lab work from
another student, or copying information from the internet without giving your source
proper credit. Your parents/guardians and the school administration will be notified.
5. Food and/or drink are not permitted during labs. This is for safety reasons!
WHAT TO EXPECT FOR WORK LOAD
Biology 11 is a senior science class. As such, it will have a heavier workload than any of the
junior science classes you have experienced. This means you will probably have to do
homework almost every night, and in addition may have to do some review too. There is a
lot of vocabulary in Biology, so expect to have to learn a lot of new words. There is also a lot of
reading. By the end of the course, you will have hopefully improved your skills to read and write
in a scientifically precise and objective orientated manner.
Biology 11 will also have many labs. You will be expected to attend these and participate. There
will be some animal dissections, please inform the teacher right away if you are not
comfortable with these for religious or personal reasons. It can be expected that every lab
will have a lab report that must be handed in for marks. The ultimate goal of labs is to reinforce
the course material and provide you with an opportunity to develop your lab skills.
TEXTBOOK AND SUGGESTED SUPPLIES
3 ring binder
Pencils
Pencil crayons
Rulers
Calculator
Glue sticks
Pens
Lots of lined paper
Colored pens
Biology 11 Textbook
My textbook number is _____________________.
FROM THE TEACHER
There are a lot of exciting and interesting things to learn in Biology 11- I hope you enjoy
the course!! I encourage you to try your best. If you do, I will always be willing to help
you!
Best Regards,
Ms. Trevelyan
3
4
Building a Science Vocabulary!
This is the longest word in the English language! What do you suppose it means? Do you think
there are hints in the word itself?
____________________________________________________________________________
____________________________________________________________________________

One challenge of biology to students is that it introduces a large
number of new words. These words are used to name or
describe living things and their parts, functions, and processes.

In biology, many words are built from Greek and Latin terms
that serve as root words

Word roots can be added to other word roots. Prefixes can be added at the beginning of the
word, and suffixes can be added to the end. In this way, words are produced which other
biologists can understand, and which otherwise might take one or more whole sentences to
express.

The root cyto is a good example. It comes from a Greek word meaning hollow vessel. In
biology, cyto always means cell. This gives rise to words like cytology. The suffix –ology
means the study of. Therefore, cytology is the study of cells.

On the next page is a list of some greek and latin root words commonly used in biological
terms. You are NOT expected to memorize these! However, you might start to recognize
some of these as you develop your vocabulary in biology.
1.
2.
3.
4.
5.
dicephalosis is superior to monocephalosis
gymnopodosis
erythrocephalis
postautocardosis
rhinorrhea
two heads are better than one
barefootedness
redhead
after his own heart
runny nose
5
ROOT WORK LIST: MEANING OF WORD ROOTS, PREFIXES, AND SUFFIXES
USED IN BIOLOGY
a, an without anemia
ab away from abnormal
ad, af near, toward adrenal, afferent
alb white albumin
algia pain neuralgia
amphi both amphibious
anti against antitoxin
aqua water aquatic
archae ancient Archaeopteryx
arthr joint arthritis
ase enzyme lipase
auto self autobiography
bi two or twice biceps
bio life biology
blast that which will germinate
blastula
brachi arm brachial
card heart carditis
carn flesh carnal
caryo nucleus of a cell eucaryote
cephalo head cephalothorax
chloro green chloroplast
chondr cartilage Chondrichthyes
chromo color chromosome
cide kill bactericide
coel cavity coelom
com, con with community
costa rib intercostal
cyst capsule nematocyst
cyto, cyte cell leukocyte
decid to cut off deciduous
dendr tree dendrite
dent, dont tooth denture, orthodontist
derm skin epidermis
di two diatomic
dis, dys ill or bad disease
eco household ecology
ecto outer ectoderm
ectomy removal appendectomy
emia blood anemia
endo inner endoderm
enter intertine enteric
epi on, at, beside epidermis
erythro red erythrocyte
eu true eucaryote
ex out exterior
fer bearer Rotifera
gastro stomach gastric juice
gen producing antigen
gymno naked gymnosperm
hemo blood hemoglobin
herb non-woody plant herbarium
hepato liver hepatic duct
hetero other heterosexual
homo, homeo same homogeneous
hyper above, excessive hyperacidity
hypo below, not enough
hypothyroidism
ia, iasis disease pneumonia
ichthys fish ichthyology
inter between interspecies
intra within intraspecies
iso same isoptera
itis inflammation of appendicitis
kin motion cytokinisis
lac milk lactose
leuco, leuko white leukocyte
logy study of biology
lysis dissolving cytolysis
macro large macronucleus
mal bad malnutrition
mega very large megaspore
meso middle mesophyll
meta beyond or after metamorphosis
micro small microbe
mito thread mitochondrion
mono one monoculture
morpho shape, form morphology
myo muscle myofibril
nema thread nematocyst
nephr kidney nephritis
neuro nerve neurology
oma tumor or swelling sarcoma
omni all omnivore
ophth eye ophthalmology
orni bird ornithology
ortho straight orthoptera
osis act, condition acidosis
osteo bone osteopath
oto ear, otitis
ovi, oo egg, oviduct oocyte
para beside parathroid
patho disease pathology
ped, pod foot milliped
peri around pericardium
phago eating phagocyte
pheno to show phenotype
photo light photograph
phyll leaf mesophyll
phyto plant saprophyte
pino to drink pinocytosis
plasma form cytoplasm
plast particle chloroplast
poly many polysaccharide
post after, behind posterior
proto first protozoa
pseudo false pseudopod
pter wing diptera
pulmo lung pulmonary
renal kidney adrenal glands
rhea, rrhea flow or discharge
diarrhea
rhino noserhinoceros
sal salt saline
sclero hard arteriosclerosis
soma body chromosomes
stom mouth stomata
sym, syn binding together sympathy
therm heat thermometer
trop turn phototropic
troph nourishment autotrophic
viv living viviparous
vore to devour carnivore
xeros dry xerophyte
zo animal zoology
zyg united zygote
6
PART A:
Your task is to analyse each of the following words with the help of a good
dictionary. Separate each word into its parts, looking up and recording the meaning
of each part. Then look up and record the meaning of the combined term.
1. biology
2. ecology
3. biosphere
4. autotrophic
5. heterotrophic
6. photosynthesis
7. saprophyte
8. carnivore
9. herbivore
10. omnivore
11. commensalism
12. bacteriophage
13. gametophyte
14. sporophyte
15. mesophyll
16. monocotyledonous
17. dicotyledonous
18. parthenogenesis
19. metamorphosis
20. ectothermic
21. endothermic
22. hypothalamus
23. leukocyte
24. erythrocyte
25. pericardium
7
PART B:
The names at various levels of classification are often made up of Greek or Latin
roots. Follow the same procedure as above with these terms:
1. Tracheophyta
2. Gymnospermae
3. Basidiomycetes
4. Ascomycetes
5. Chiroptera
6. Orthoptera
7. Porifera
8. Arthropoda
9. Coleoptera
10. Homoptera
11. Hemiptera
12. Hymenoptera
13. Echinodermata
14. Platyhelminthes
15. Rotifera
16. Osteichtyes
17. Chondrichthyes
Part C: Now it is your turn. Using Greek or Latin root words, create four of your own biological
terms!
Word
Definition
1.
2.
3.
4.
8
OVERVIEW:
1. Observation
2. Question
3. Prediction/
Hypothesis
4. Experimentation
5. Conclusion

Review of the Scientific Method

Science is ultimately based on observation (perceiving objects or events
using one of the five senses).

Observations often lead to questions, which lead to experiments to
answer the questions.

A prediction is an expected outcome. A hypothesis is a testable
statement that proposes a possible explanation for an observation. You can
make a hypothesis using a prediction.
Formal hypotheses use an if (statement or relationship is true) then (you would expect a
certain result) format.
e.g. If Fertilizer A causes plants to grow, then plants given Fertilizer A will be taller than plants
that do not receive it


Fertilizer A is the independent variable; it is the thing being tested (goes on x-axis)
Taller is the dependent variable, it is thing being measured (goes on y-axis)
**The dependent variable depends on the independent variable**

The hypothesis is then tested by experimentation. An experiment compares two groups:
1. Experimental Group- receives some kind of treatment (e.g. Fertilizer A)
2. Control Group- receives no treatment (e.g. no Fertilizer A)
Everything about the two groups except the treatment you are testing must remain exactly the
same. Why do you think this is?
____________________________________________________________________________
____________________________________________________________________________
The variables that are kept the same are called controlled variables. Examples in this case
include same temperature, same amount of water, same amount of sunlight for the treatment
group and the control group.
Collecting Data
You can collect numerical data such as height in centimetres (quantitative data) or nonnumerical data such as red (qualitative data)
Key terms:
prediction
Fertilizer A
experimental
If…then
experimentation
question
observation
hypothesis
qualitative
quantitative
experiments
independent
taller
dependent
control
9
Quantitative data is usually organized into a table and/or graph. Draw a linear graph below
using the data from the table. Remember to include a title and label the x-axis and y-axis.
Day
1
Average height of
Treatment (cm)
10
Average height of
Control (cm)
7
5
25
15
10
45
20
15
60
35
20
68
45
treatment
control
Which form of data presentation do you find easier to read, the table or the graph? Explain why.
____________________________________________________________________________
____________________________________________________________________________
Conclusion
 Scientists will examine the data to determine whether the hypothesis was rejected or
accepted. Often, they use statistics to see if the difference between treatments was real or
just happened by random chance. A large number of replications (30+) helps reduce errors
in data.

Technically, a hypothesis can be supported but never “proven” true. You would say, rather,
you failed to reject your hypothesis if your data supported it.

The conclusion should include:
1. A statement of the purpose of the experiment
2. If the hypothesis was accepted or rejected
3. Relevant data to support or reject #3, or if data was inconclusive
4. Any problems that occurred during experimentation
5. The next step in building on what was learned- future experiment(s)
What is a Theory?
A theory is an explanation for natural events that is based on a large number of observations. It
is important to realize that theories explain what we observe. Theories must be falsifiable and,
if new data does not support it, theories can be modified or changed.
Example: the Germ Theory explains why we get sick and why we get infections. It uses
observation of viruses and bacteria as well as data from those who get ill to create a theory on
what causes the illness.
Key terms:
replication
graph
explanation
accepted
table
Failed
rejected
Germ theory
large
modified
falsifiable
10
The Scientific Method (aka the Process of Science)
1. Put the following steps of the scientific method in the proper order:
____
Organize and analyze the data
____
State the hypothesis
____
Identify the problem
____
State the conclusion
____
Design and carry out an experiment
____
Make an original observation
____
Ask a question
2. Match the term with its definition
1.
Theory
____
A. Suggested explanation to a problem or observation
based upon known information
2.
3.
Law
Hypothesis
____
____
4.
Experiment
____
5.
Variable
____
6.
Control
____
7.
Data
____
B. Used to test a hypothesis
C. Anything that can affect the results of an
experiment
D. Observations and measurements made during an
experiment
E. Part within the experiment that is maintained
without change in order to provide a comparison
for the part of the experiment containing the
variable
F. Many hypotheses that have been tested and
supported by a great amount of evidence over a
long period of time
G. Statement describing (but not explaining) a natural
event or phenomenon
8.
Conclusion
____
9.
applicaiton
____
H. New use to which results are put or new technique
developed
I. A summary that explains whether or not the data
support the hypothesis
11
3. A hypothesis statement may start with “if” (referring to cause), followed by the word
“then” (referring to effect). For example: If I brush my teeth twice a day, then I can
protect my teeth from decay. Complete the following hypothesis statements:
a. If heat is applied to a liquid, then_______________________________________
b. If _____________________________________________ then living things in that
ecosystem will be affected
c. If a student misses many summer school classes, then _______________________
___________________________________________________________________
d. If a wet rag is wrung out in outer space, then ______________________________
___________________________________________________________________
4. Develop a hypothesis for what may happen in the following situations:
a. You have a long distance to travel when your gas needle signals empty
Hypothesis: ________________________________________________________
__________________________________________________________________
b. The element on top of your stove is a bright red colour
Hypothesis: ________________________________________________________
__________________________________________________________________
c. The soup you are eating is much too salty
Hypothesis: ________________________________________________________
__________________________________________________________________
5. The table below lists observations made of a candle, both before and after burning.
Check QL for qualitative observation (characteristics) or QT for quantitative observations
(measurements). Add a comment or explanation if you need to justify your choice.
Observation
1. The candle is cylindrical in shape
2. It is 2 cm in diameter
3. The length is about 15 cm
4. The length decreases during the
observation period
5. The candle is translucent
6. The last 2 mm of the wick glowed red
QL
QT Comment/Explanation
12
6. What can you conclude from the following graphs?
Conclusion from table: Student’s Favourite
Juices: _____________________________
___________________________________
___________________________________
___________________________________
___________________________________
Conclusion from table: Unemployment
Rates: _____________________________
___________________________________
___________________________________
___________________________________
___________________________________
7. In the 1950’s scientists were running field experiments to compare three insecticides:
Zap, Rid and KFB Formula 9 (KFB-9 for short). The scientists were employed by Y.U.K.
Chemicals Inc., makers of Zap. They designed the field tests in order to see whether or
not further research into the problem was necessary. The chemicals were sprayed on 3
separate fields and the experiment was repeated three times. Sometime after spraying,
the scientists swept the area above the fields with large nets to capture any surviving
flying insects. The bugs were counted and the table and graph that follows shows the
data obtained from those field tests.
Field
Number
Insecticide
Used
# of Surviving bugs found
1
Zap
Trial 1
48
Trial 2
63
Trial 3
52
Trial 4
54.3
2
Rid
119
103
136
119.3
3
KFB-9
110
130
114
118
13
Comparing Average
Effectiveness of 3 Insecticides
120
100
80
60
40
20
0
ZAP
Rid
KFB-9
a. Give one possible hypothesis for this experiment
b. Why would some scientists argue that this was not a fair test?
c. What factors must be controlled in this experiment?
d. Do you think this was a controlled experiment? Why or why not?
e. What is the conclusion for these results?
8. Think of a testable question you have and describe how you would design an
experiment to test it.
Question: __________________________________________________________________
Hypothesis: _________________________________________________________________
Treatment: ________________________________________________________________
Control: ___________________________________________________________________
Independent Variable: _______________________________________________________
Dependent Variable: ________________________________________________________
(Proposed) Conclusion: ______________________________________________________
14
Unit 1: Process of Evolution






Living things evolve over time.
Evolutionary change:
-role of DNA in evolution as a hereditary material
-five agents of evolutionary change
 Mutation
 Genetic drift
 Gene flow
 Non-random mating
 Natural selection
Development of the theory of evolution
 Lamarck
 Darwin
Models of evolution
 Gradual change model
 Punctuated equilibrium model
Speciation:
-divergent evolution
-convergent evolution
-co-evolution e.g. flowers and pollinators
Trends in complexity
 Body transport
 Gas exchange
 Cephalization
 Reproduction
 Symmetry
 Coelom
 Tissue development
 Vascularization
Artificial selection and genetic modifications
 Plant and animal breeding
 Gene therapy and GMO’s
 Ethical considerations
What is the role of DNA in evolution and biodiversity?
What characteristics allow organisms to live in unique environments?
How might the range of abiotic and biotic characteristics on Earth help us to
understand space exploration (ex. Extreme environments…Mars or the moon?)
What will the discovery of new fossils and genes reveal about the early evolution of
plants and animals?
15
16
Section 1: CHARACTERISTICS OF LIVING THINGS
Sometimes it is not easy to tell if something is alive
e.g. fire-> “eats”, “grows”, needs oxygen, “dies”, but we know it is not living (it is in fact a chemical
reaction)
How do we define “living”? It must:
1. Respond to the environment e.g. poke- ouch!
2. Need energy (aka “food”)
a. Plants are AUTOTROPHS and get food automatically using photosynthesis
e.g. sunlight + CO2 + H2O  C6H12O6 (sugar) + O2
b. Animals are HETEROTROPHS and obtain their food from other organisms
e.g. eating other animals and plants
3. They grow
e.g. baby  child  adult (bigger, more cells)
4. They reproduce
-old organisms die and need to be replaced
-some reproduce asexually (one parent producing a genetically identical offspring)
-some reproduce sexually (two parents producing a genetically different offspring)
-some species can do both! E.g. fungi
5. They must get rid of waste
-animals  sweat, feces, urine, CO2
6. They are made up of cells
-viruses are NOT made up of cells!
-cells are the building blocks of all living things
-PROKARYOTIC cells are the most primitive and are lacking many structures
-no membrane bound organelles (e.g. mitochondria, chloroplasts…) or nucleus
-very small
-include the Kingdoms Archaeobacteria and Eubacteria (bacteria)
-EUKARYOTIC cells are more complex
-have membrane bound organelles and a nucleus
-bigger than prokaryotes
-include the Kingdoms Animalia, Plantae, Fungi, and Protista
Key terms:
energy
reproduce
cells
grow
fire
prokaryotic
respond
asexually
heterotrophs
sexually
waste
bacteria
autotrophs
eukaryotic
17
Review Questions- CHARACTERISTICS OF LIVING THINGS
1. How do autotrophs differ from heterotrophs?
2. How are prokaryotic cells different from eukaryotic cells? Which one are you made up
of?
3. Which of the above characteristics do you think is most critical in defining a living
organism? Explain why.
4. Viruses are in the “grey area” between living and non-living things. Research the
characteristics of viruses and decide whether you categorize viruses as living or nonliving. Support your decision.
5. Movement is often used as a criteria to determine if an organism is living, but this is not
always accurate. Explain why.
18
Section 2: DNA and Protein Synthesis
Part I- The Nucleus and DNA: Control Centre of the Cell
 Every cell in your body has a specific _JOB__- but how do they become specialized?
E.g. hair cells vs. skin cells vs. retina in the eye

The _NUCLEUS_ in the cell contains the master set of
instructions that tells the cell:
a. what it will _DO (IT’S JOB)
b. how it will function
c. when it will _REPRODUCE_ and _GROW_
d. when it will die
But how does the nucleus do this? How does it send messages to the rest of the cell?
* The nucleus contains _DNA_, which carries the master set of _INSTRUCTIONS__for cell
function *

DNA (_DEOXYRIBONUCLEIC ACID__) is a double stranded helix that looks like a twisted
ladder

the sides of DNA are made of _SUGAR_ and _PHOSPHATE___

the steps of DNA are made up of 4 _BASES__:
Adenine
Cytosine
Guanine
Thymine
Base Pairing Rules

ADENINE (A) always pairs with __THYMINE_ (T)

CYTOSINE (C) always pairs with _GUANINE_ (G)
The bases in DNA are held together by weak
HYDROGEN bond. These are cut apart by enzymes
to allow for DNA REPLICATION and PROTEIN
SYNTHESIS.
Key terms:
job
phosphate
instructions
Guanine
Protein synthesis
grow
hydrogen
Cytosine
sugar
replication
do
Thymine
dna
bases
Nucleus
reproduce
Deoxyribonucleic acid
adenine
19
Part 2- The Role of DNA in Hereditary Traits and Evolution
1. DNA has many functions:
A. DNA contains INSTRUCTIONS for all CELL FUNCTIONS and, therefore, DNA indirectly
controls all of the functioning of all living things.
B. DNA determines the HEREDITARY TRAITS of an individual
C. DNA _EVOLVES__ (changes through mutations and recombination). This allows for new
characteristics & abilities to appear which may help an individual to survive &
reproduce.
D. Self replication: DNA has the ability to make COPIES of itself
2. The arrangement of bases in DNA directs all cell activity
-the bases are like letters that carry a message (_CODE_)
-the code gives instructions for a specific task.
3. Genes are found on chromosomes
 A _GENE_is a small segments of DNA found at specific places on a
chromosome that code for a protein. Each chromosome carries 1000s
of genes!

genes can vary in length from 100s to 1000s of BASES

the arrangement of bases will decide what kind of protein is produced
e.g. ACCATAGG  makes protein “A”
AGGCGTTA  makes protein “B”

only certain genes are _ACTIVATED_ in each type of cell. Depending which genes are
active, different proteins are produced, and this causes cells to have different functions.
E.x. You do not have skin pigment genes being used by your stomach cells
ONE GENE  ONE TYPE OF PROTEIN  ONE FUNCTION
4. MUTATIONS can change DNA and affect protein structure and function
 If a mutation is beneficial and helps survival, it can lead to EVOLUTION!
 mutations are RARE, RANDOM and usually HARMFUL…more on this later!
Key terms:
Gene
Cell functions
instructions
bases
evolves
evolution
activated
hereditary
code
mutations
traits
Copies
20
Section 3: Introduction to the Theory of Evolution
Why is evolution important and relevant?
Without evolutionary theory as a guiding framework, biology is just a
collection of facts.
“Seen in the light of evolution, biology is perhaps, intellectually
the most satisfying and inspiring science. Without that light, it becomes
a pile of sundry facts – some of them interesting or curious but making
no meaningful picture as a whole.” Theodosiuos Dobhansky, 1973
What do we mean by the term evolution?
1. All species share a common ancestor.
2. Species have changed through time, ie they have adapted to different habitats.
These 2 ideas are sometimes referred to as “descent with modification.”
Today we sometimes use a more specific definition which refers to genetics:
Evolution is … “A change in the frequency of alleles in a population over time.”
We will study the 4 aspects of evolution, we will look at evidence for evolution, we will look at
theories of evolution, how new species evolve, and finally patterns of evolution.
Theories of evolution- Chp 15 pg. 376 (Lamark) and pg. 386, pg. 398 (Darwin)
Evidence for evolution –Chp 15-3 pg. 382 – 385
Speciation –Chp 16-3 pg. 404-410
Patterns of evolution – pg 435- 439
Vocabulary
Here are some terms that you should familiarize yourself with as we go through this unit:
Evolution
Theory
Fossil
Natural Selection
Artificial Selection
speciation
Reproductive isolation
Coevolution
Fitness
Struggle for existence
Adaptation
Survival of the fittest
Descent with modification
Behavioural isolation
Geographical isolation
Common descent
Homologous structure
Vestigial organ
Directional selection
Stabilizing selection
Temporal isolation
Adaptive radiation
Disruptive selection
Genetic drift
Founder effect
Convergent evolution
Genetic equilibrium
Allelic frequency
Punctuated equilibrium
Hardy-Weinburg
principle
Because evolution follows changes in the environment, to gain an appreciation of evolution it is
helpful to review the changes that have occurred on earth since its formation
21
Section 3.1- A BRIEF OVERVIEW OF HISTORY OF LIFE ON EARTH
1. Formation of the earth’s__OCEANS__ and __ATMOSPHERE___ filled up.
2. Ancient atmosphere consisted of __CH4___, NH3, CO, CO2, N2, and H2O, but lacked free
O2. There was intense ___LIGHTENING___and UV radiation.
3. Rocks 3.5 bya contain fossils of _ARCHAEOBACTERIA__. Organisms are heterotrophic
absorbing organic molecules from surrounding water. Survived anaerobically
(without_OXYGEN___) as photosynthesis had not yet occurred.
4. First photosynthetic eubacteria found. _OXYGEN__is produced.
5. Oxygen began to accumulate in the__ATMOSPHERE__.
6. Origin of aerobic metabolism and eukaryotes.__PROTOZOANS__, algae, fungi and
simple, worm-like soft bodied animals evolved.
7. Animals with _HARD PARTS__(shrimp-like arthropods) evolved in the ocean. As well as
primitive chordates (animals with backbones).
8. Invasion of land begins. _PLANTS_first and then lobe-finned fish.
9. Origin of__AMPHIBIANS_.
10. Major radiation of insects, amphibians, cone-baring plants, and reptiles with
__AMNIOTIC__eggs evolve.
11. A few reptile lineages give rise to ___MAMMALS__ and dinosaurs.
12. Dinosaurs rule!
13. Mass __EXTINCTION__of Dinosaurs.
14. Mammals undergo adaptive radiation. Mammals found on all_CONTINENTS__.
Key terms:
Plants
Lightening
Oxygen
extinction
Mammals
Amniotic
Oxygen
amphibians
CH4
4.6 billion
Hard parts
oceans
Protozoans
Years ago
Continents
Amphibians
Atmosphere
archaeobacteria
22
Section 3.2- The Theory of Evolution is Born!
Consider the following:
1. At one time, there was no life on Earth. Today, the Earth is full of living organisms
2. 99.9% of all organisms that ever existed are extinct
3. Organisms that exist today did not necessarily exist millions of years ago
These concepts suggest that organisms have changed through time= EVOLUTION
Where did the theory of evolution come from?
Early time- 17th Century
 Most people believed in _CREATIONALISM__, which considered that all life was
created just as it is now. Essentially, all plants and animals _APPEARED__ at the same
time and have never changed.
 Creationism suggests that species are “_FIXED_.” Creationism also implies that earth
itself also has never changed, mountains have always been _MOUNTAINS__ and the
age of the earth is only about _10,000__ years old. These ideas were _NOT_ based on
any evidence, but instead on a _BELIEF_.
18th Century
 Naturalists began systematic classification systems, especially _LINNAEUS_ (17071778). Many naturalists noticed that groups of organisms had similar
__CHARACTERISTICS__, appeared to be _RELATED_ and appeared to be suited to their
particular _ENVIRONMENT__.
 European naturalists travelled more widely and discovered more fossils, which clearly
showed that organisms have _NOT_ always looked the same. _EXTINCTIONS_were
also observed (eg the Dodo bird), so species were not “fixed.”
19th Century
 During this time, exploration and science flourished even further
 Lamarck, Wallace and Darwin developed theories about how a species can change over
time
Key terms:
millions
mountains
extinctions
Linnaeus
appeared
characteristics
belief
not
No life
theories
99.9
fixed
environment
theory
10,000
creationism
23
1. JEAN-BAPTISTE LAMARCK (1774-1829)
 Lamarck proposed animals evolve
through inheritance of acquired
characteristics (not true!).
 Suggested individuals capable of
transforming through want/need
 For example, if a giraffe stretched his
neck a lot, his neck would become
longer and his offspring would inherit
longer necks.
2. CHARLES DARWIN (1809-1882) and ALFRED WALLACE (1823-1913)
 In 1831, Darwin went on a voyage around the world on the HMS Beagle.
The trip took 5 years!
 Darwin collected plant and animal samples and studied the new species
etc. discovered on the journey
 Darwin noticed there was a pressure on organisms to survive and that
the most well adapted organisms are more likely to survive and pass on their
traits to their offspring.

He coined the term NATURAL SELECTION to explain this process. It suggested that
individuals were fixed and unchanging, and those well adapted survived and passed on
their traits to their offspring.

Darwin published a book called THE ORIGIN OF SPECIES in 1859 together with ALFRED
WALLACE, who had developed the same theory of natural selection independently.
20/21st Century
 Discovery of the structure of _DNA_, ability to compare DNA and proteins of different
organisms, and the information from _GENETIC_ studies support the theory of natural
selection. Geologists prove the earth is about __4.6 BILLION_ years old, plenty of time
for species to evolve.
Key terms:
HMS Beagle
Natural
selection
DNA
adapted
Origin of species unchanging
transforming
pressure
inherit
genetic
Alfred Wallace
collected
Pass on
4.6 billion
24
Acquired
characteristics
Review Questions- LAMARCK’S THEORY
1. Describe Lamarck’s three assumptions (see page 376) :
a) Tendency towards perfection
-all organisms have an inborn tendency toward complexity and perfection. They
are continually changing and acquiring features that help them live more
successfully. Ex. urge to fly  flying birds
b) Use and Disuse
-if an organ or body part is used, it will change accordingly; if not used, it will
decrease in size
c) Acquired Traits
-Lamark believed that acquired traits could be passed on (inherited) by offspring
Why Life Changes According to Lamarck





One of the earliest theories of change (evolution) was proposed by LAMARK.
He observed that each kind of animal had ADAPTED to live efficiently in its
environment.
These adaptations occurred gradually, through time due to the way the animal USED its
body parts.
Those body parts not regularly used would DISAPPEAR because they were not needed
for survival . (Law of use and disuse.)
Lamarck explained evolution through INHERITANCE of acquired characteristics ie.
Characteristics are passed on to the next GENERATION.
For example:
 The giraffe is a leaf-eating animal
 The giraffe lives in regions where vegetation is not abundant and leaves are not near the
GROUND.
 Giraffes have to STRETCH to reach the leaves.
 Through time this stretching would cause the neck and the front legs to ELONGATE.
 Changes in body shape caused by the way giraffes stretched their bodies was passed on to
their OFFSPRING.
 Therefore, all future GENERATIONS would have these characteristics.
 At the same age, the YOUNG would have longer necks and legs than the previous
generation.
Keywords
Stretch
Young
Disappear
Ground
Lamark
25
Used
Generations
Generation
inheritance
Offspring
Elongate
adapted
Review Questions- DARWIN’S THEORY
Describe the 5 points of Darwin’s Theory of Evolution (pg 386):
1. Individual organisms differ, and some of this variation is heritable
2. Organisms produce more offspring than can survive, and many that do survive do not
reproduce
3. Because more organisms are produced than can survive, they compete for limited resources
4. Each unique organism has different advantages and disadvantages in the struggle for
existence. Individuals best suited to their environment survive and reproduce, passing on their
traits to their offspring, causing populatinos to change over time.
5. Species alive today are descended with modification from ancestral species that lived in the
distant past.
Why life Changes according to Darwin






Charles Darwin recognized the importance of the TRAITS/CHARACTERISTICS
Darwin observed much VARIATION within a species eg. the height of people.
He also had read Malthus and realized that way more babies in most species were born
than survived to adulthood
The differences between individuals made it possible for some to be more
SUCCESSFUL than others in finding food, escaping predators and ultimately surviving.
This idea is called “NATURAL SELECTION.”
If the environment CHANGES, natural selection will result in different individuals
surviving.
For example:
 The ancestors of modern day giraffes had SHORTER necks.
 Those ancestors had VARIATION within their population.
 Longer necked giraffes were able to reach the highest leaves where MORE food was
available.
 Therefore, longer-necked giraffes were HEALTHEIR and able to produce more
BABIES.
 The subsequent generation of giraffes had a HIGHER proportion of individuals with
longer necks.
 The PROCESS occurred over and over again through thousands of generations until
today giraffes have very long necks (but with the same number of vertebrae).
Keywords
Babies
Variation
Natural selection
Traits/characteristics Environment
26
Shorter
More
Healthier
Changes
Successful
higher
Process
Variation
Section 3.3 EVIDENCE FOR EVOLUTION
At this point (18th and 19th centuries) evolution meant:
Organisms change over time
Organisms have a common ancestor
1. FOSSILS
 Can be dated
 Older organisms are simpler in form than modern organisms
 show gradual series of changes in form
 Indicate that mass extinctions occurred
2. HOMOLOGOUS STRUCTURES
 Body parts of different organisms that on the surface look
different, but anatomically are very similar.
 Often have different functions
 E.x. forelimbs of mammals (human, cat, whale, bat)
 Suggests that all mammals evolved from a common ancestor
and that they adapted to different habitats. Fossils evidence has
supported this idea. This process is called divergence.
3. ANALOGOUS STRUCTURES
 Body parts of different organisms that have
similar functions and superficial
appearance but very different anatomy.
 Ex. the flippers of penguins, sharks and
dolphins
 Suggests that if 2 unrelated organisms
occupy a similar environment then they will
face similar selective pressures and will
begin to look like one another.
4. VESTIGIAL STRUCTURES
 Structures with no current function,
 Are homologous to functional structures in related
organisms.
 Ex. ear muscles and body hair in humans, remnant
leg bones in whales
 Structure may have had a function in an ancient
ancestor
 Over time the structures gradually disappear.
Key terms:
changes
leg
dated
different
similar
27
similar
no
extinction
Common ancestor
pressures
function
simpler
disappear
divergence
5. ARTIFICIAL SELECTION
 Rapid, heritable changes have been produced in domestic
animals and plants by selectively breeding organisms with
desired features.
 If differences as vast as those occurring between the Chihuahua
and the Great Dane can be produced in a few thousand years of
artificial selection by humans, it seems likely that much larger
changes could occur in hundreds of millions of years.
6. MOLECULAR BIOLOGY
 Biological molecules such as proteins (amino acid sequence) or DNA (genetic code) can
be compared between different organisms.
 The more similar the biological molecules, the more closely related the different
organisms are
7. EMBRYOLOGY




Embryology= the study of embryos (an unborn or unhatched animal)
Embryos of many different kinds of animals look very similar and it is often difficult to
tell them apart. Many traits of one type of animal appear in the embryo of another type
of animal.
E.x. fish embryos and human embryos both have gill slits. In fish they develop into gills,
but in humans they disappear before birth.
This shows that the animals are similar and that they develop similarly, implying that
they are related, have common ancestors and that they started out the same, gradually
evolving different traits, but that the basic plan for a creature's beginning remains the
same.
Key terms:
proteins
similar
larger
domestic
closely
28
embryology
ancestors
breeding
traits
DNA
Desired features
similar
related
EVIDENCE FOR EVOLUTION ASSIGNMENT
Instructions:
For this assignment, you will present images that illustrate evidence for evolution. Your pictures
may be hand drawn or printed from the internet. They should be coloured and include a brief
description of what they are showing and how this supports the theory of evolution.
Images should include:
1. Fossils – Make a photo gallery of fossils that show:
a. The oldest organisms are simple in form
- check out the oldest fossils or fossils of the Cambrian period
b. Organism change over time
- this will require several images showing an organism changing over
time
- check out the Burgess shale fossils as a starting point
c. There have been mass extinctions
-find a fossil of a species that no longer exists today- like a dinosaur!
2. Homologous Structures
-Find a picture illustrating homologous structures and colour the bones in the forelimb
of each mammal
3. Analogous Structures
-Find pictures of unrelated organisms with similar appearing body parts. Explain the
origin of each organism.
4. Vestigial Structures
-Find a diagram of a person showing at least 5 vestigial structures. State the original use
of each structure.
5. Artificial Selection
-Choose a domesticated animal to illustrate the numerous varieties of a single species.
6. Similarities in Embryology
-find images of 3 organisms that look similar in the early stages of development
You can present your images as a booklet, poster, or pamphlet. Give your assignment a title and
be sure to include your name, block and date.
Due date: _____________________
Total Marks: _________
29
USING COMMON MOLECULES TO COMPARE SPECIES
Examining the relationships between biological molecules, such as proteins or DNA can tell scientists how closely
related organisms are. The more similar these molecules are, the more recently the organisms had a common
ancestor. Follow the directions for each table.
1.
There are 146 amino acids in the protein hemoglobin. This table shows a portion of the amino acid sequence for
hemoglobin for 6 different mammals. Circle or highlight the amino acids in the chimp, gorilla, monkey, horse, and
kangaroo sequences that differ from those in the human sequence.
Amino Acid #

Human
Chimp
Gorilla
Rhesus
Monkey
Horse
Kangaroo
Amino Acid #

Human
Chimp
Gorilla
Rhesus Monkey
Horse
Kangaroo
2.
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
thr
thr
thr
leu
leu
leu
ser
ser
ser
glu
glu
glu
leu
leu
leu
his
his
his
cys
cys
cys
asp
asp
asp
lys
lys
lys
leu
leu
leu
his
his
his
val
val
val
asp
asp
asp
pro
pro
pro
glu
glu
glu
gln
leu
ser
glu
leu
his
cys
asp
lys
leu
his
val
asp
pro
glu
ala
lys
leu
leu
ser
ser
glu
glu
leu
leu
his
his
cys
cys
asp
asp
lys
lys
leu
leu
his
his
val
val
asp
asp
pro
pro
glu
glu
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
asn
asn
asn
asn
asn
asn
phe
phe
phe
phe
phe
phe
arg
arg
lys
lys
arg
lys
leu
leu
leu
leu
leu
leu
leu
leu
leu
leu
leu
leu
gly
gly
gly
gly
gly
gly
asn
asn
asn
asn
asn
asn
val
val
val
val
val
ile
leu
leu
leu
leu
leu
ile
val
val
val
val
ala
val
cys
cys
cys
cys
leu
ile
val
val
val
val
val
cys
leu
leu
leu
leu
val
leu
ala
ala
ala
ala
ala
ala
his
his
his
his
arg
glu
The table shows the number of amino acids in cytochrome c that differ between several organisms and humans.
Cytochrome c is a protein found in mitochondria. It is often studied because most organisms have mitochondria and
therefore they have cytochrome c. Rewrite the information in the blank table by listing the organisms IN ORDER with the
greatest number of differences at the top and the least at the bottom.
Species Comparison
Human—chimp
Human—fruit fly
Human—horse
Human—pigeon
Human—rattlesnake
Human—red bread mold
Human—rhesus monkey
Human—screwworm fly
Human—snapping turtle
Human—tuna
Human—wheat
# of differences
0
29
12
12
14
48
1
27
15
21
43
Part IV Questions:
Use all of the above tables to answer the questions below.
1. On the basis of hemoglobin similarity, which organism appears to be most closely related to humans? Least related?
2.
On the basis of cytochrome c similarity, which organism appears to be most closely related to humans? Least related?
3.
If the amino acids sequences in the proteins of two organisms are similar, why will their DNA also be similar?
30
Species Comparison
4.
# of differences
Many biologists believe that the number of
differences between the proteins of different
species indicates how long ago the species
diverged from a common ancestor. Why do these
same biologists believe that humans, chimps, and
gorillas diverged from a common ancestor only a
few million years ago?
Section 3.4- EVOLUTION BY
NATURAL SELECTION in FIVE STEPS
STEPS:
1) Variation within a Species
-Individuals within the species are not _IDENTICAL__
-Variation in colour, size, _SMELLING ACUITY (sharpness)_, RESISTANCE to disease, speed,
allergies.
2) _Environmental Pressures/Changes_
Ex. Flooding, increase/decrease temperatures, predators, drought, lack of food, lack of
space.
3) _ Differential Reproduction __
Selection occurs, you have babies or you don’t have babies
Who selects? ….Nature or the _ENVIRONMENT_.
4) __Survival of the Fittest__
-Only some individuals get to reproduce and leave viable offspring, (VIABLE_-offspring that
can have their own babies ie. Not _STERILE_)
-Some traits (those that are NOT advantageous) _DISSAPEAR_ from the species.
5)_ Evolution Occurs _
-The next generation exhibits an increase in the frequency of the “best” traits.
31
Key terms:
Differential Reproduction Sterile
disappear
Environment
identical
viable
ability
resistance
smelling acuity
Evolution Occurs
Survival of the fittest
Environmental Pressures/Changes
HOMEWORK: Using the 5 Steps of Natural Selection explain how:
1. the length of the giraffe’s neck evolved.
2. the polar bear’s fur color evolved
3. the vocalizations of the killer whale evolved.
Section 3.5 -THE SELECTION PROCESS
BACKGROUND
1. Genetics
 Natural selection acts separately on each trait or characteristic of an organism.
 Every trait or feature of an organism is determined by at least one gene.
 Most organisms have 2 copies of every gene.
E.x. eye color  one gene that has 2 possible alleles or trait of a gene
 a blue allele (b)
 a brown allele (B).
 Typically, there is dominance between the different alleles so
that person with:
B B – brown eyes
Bb – brown eyes
bb - blue eyes


Selection can change in frequency of a particular trait eg. eye color and or the frequency
of a particular allele of a gene eg.”b” the allele for blue eyes. The % of a particular allele
in a population is called allelic frequency.
We use the term phenotype to describe the obvious characteristic or trait, while we use
the term genotype to describe the combination of alleles.
2. The Bell Curve
 The bell curve refers to the shape of a graph that illustrates the normal
distribution of traits in a population.
 Works for all traits E.x. foot length.

When environmental conditions change a certain less common phenotype can become
advantageous, as a result the curve can change or shift.
32


Populations do not decide to adapt, or
mutate, after an environmental change.
The phenotype has to already be there by
chance; otherwise the population may
become extinct.
Natural selection can change the
distribution of a trait along three paths:
directional, stabilizing, or disruptive.
Key terms:
gene
genotype
decide
characteristics
dominance
shape
change
phenotype
allele
Allelic
frequency
extinct
shift
distribution
3. THREE TYPES OF SELECTION
a) Directional selection – causes a shift in a populations phenotypic
distribution
 An extreme phenotype that was once rare is now common
 The mean value of a trait shifts in direction of the more
advantageous phenotype
b) Stabilizing Selection – the intermediate phenotype is favoured and
becomes more common
 Decreases genetic diversity
 Extreme phenotypes may be lost
c) Disruptive Selection – occurs when both extremes are favored
and the intermediate are selected against.
 Intermediate forms are selected against
 Can lead to the formation of a new species
Key terms:
advantageous
disruptive
common
against
directional
favoured
shift
stabilizing
decreases
Extremes
33
EXAMPLES OF SELECTION
For each scenario below decide which type of selection is at work.
Grass plants in Welsh Copper mines. Soil contaminated by copper from
the mines is lethal to normal grass plants, but a chance mutation
allowed one plant to grow. This plant prospered and reproduced, but
only on the contaminated soil. On normal soil it grew more slowly than
the normal plants and was easily out-competed. So now there are two
varieties growing close together
TYPE OF SELECTION:
Pesticide Resistance Warfarin is a poison used to kill rats. When warfarin was introduced, some
rat populations already contained rats with a chance mutation that gave them resistance to the
poison. Without warfarin, stabilising selection favors normal rats – resistant rats are selected
against, because they need a lot of vitamin K in their diet. Warfarin was a new environmental
factor that killed normal rats. A few resistant rats survived, reproduced and passed on the
resistance gene. They produced a new population of resistant rats.
TYPE OF SELECTION
34
The Coelacanth. This fish species was known only from ancient fossils and was assumed to have
been extinct for 70 million years until a living specimen was found in a trawler
net off South Africa in 1938. So this species has not changed in all that time.
TYPE OF SELECTION
Bacterial resistance to antibiotics. Antibiotics kill bacteria, but occasionally a chance mutant
appears that is resistant to that antibiotic. In an environment where the antibiotic is often
present, this mutant has an enormous selective advantage since all the normal (wild type)
bacteria are killed leaving the mutant cell free to reproduce and colonize the whole
environment without any competition. Some farmers routinely feed antibiotics to their animals
to prevent infection, but this is a perfect environment for resistant bacteria to thrive. The best
solution is to stop using the antibiotic so that the resistant strain has no selective advantage,
and may die out.
TYPE OF SELECTION
Sickle-cell anemia. People homozygous for this recessive allele usually die before reproducing.
Their red blood cells contain abnormal hemoglobin which makes them become sickle-shaped
and stick in their capillaries. People heterozygous for the allele
should be at a disadvantage, because their red cells can sickle
during exercise. However, people heterozygous for sickle-cell
anaemia are more resistant to malaria than people homozygous for
the normal allele. Where malaria is found, people heterozygous for
sickle-cell have an advantage and are likely to survive, reproduce and pass on the allele. This
produces populations with an equilibrium for numbers of people heterozygous for sickle-cell
and non-carriers
TYPE OF SELECTION
The Peppered Moth (studied by Kettlewell). These light colored moths are well camouflaged
from bird predators against the pale bark of birch trees, while rare mutant dark moths are
easily picked off. During the industrial revolution in the 19th century, birch woods near
industrial centers became black with pollution. In this changed environment the black moths
had a selective advantage and became the most common color, while the pale moths were
easily predated and became rare.
TYPE OF SELECTION
Birth Weight: In humans, birth weight can be represented by a typical bell curve. Babies of low
weight lose heat more quickly (surface area to volume ratio) and get ill from infectious disease
more easily, whereas babies of large body weight are more difficult to deliver through the
pelvis.
TYPE OF SELECTION
Rabbit Fur Colour: Suppose there is a population of rabbits. The color of the rabbits is governed
by two incompletely dominant alleles: black fur represented by “B” and white fur represented
by “b”. A rabbit with genotype “BB” would have a phenotype of black fur, a genotype of “Bb”
would have grey fur and a genotype of “bb” would have white fur. What type of selection
35
would occur if this population migrated to an area that has very dark rocks as well as white
colored stone?
TYPE OF SELECTION
Homework: Choose an example of each type of selection, and draw the appropriate graph to
illustrate the example. Make sure to label the axes.
Section 3.6- MECHANISMS OF EVOLUTION
-evolution occurs at the population level, with genes as the raw material
-a non-changing population is said to be in genetic equilibrium
-there are 5 mechanisms that cause a population to change, potentially leading to evolution.
These are: natural selection, genetic drift, gene flow, mutation, and non-random mating
-Hardy and Weidnberg proved mathematically that evolution will not occur in a population
unless allelic frequencies are acted upon by forces that cause change= Hardy-Weinberg
principle
-there are 5 conditions for the Hardy-Weinberg principle to work:
1. there must be no genetic drift (less likely in larger populations)
2. there must be no gene flow (no immigration or emigration)
3. there must be no mutations
4. mating must be random
5. there must be no natural selection (all individuals are equally adapted to the
environment)
-hardly any population meets all of these 5 principles in the “real world” (unlike computer
programs)
1. Genetic Drift
-any change in allelic frequency in population due to chance
-in larger populations, genetic drift is averaged out; in smaller populations, genetic drift may
lead to the loss of an allele all together
Two extreme examples of genetic drift are:
a. Founder Effect: when a small sample of a population settle in a separate location
and this leads to large genetic variation between the separated populations
36
b. Bottleneck: this is when a population declines to a very low number and then
rebounds, often having reduced variability because it originated from a low
number of individuals
Key terms:
‘real world’
allele
mechanisms
population
random
Large
conditions
declines
equally
founder
bottleneck
chance
equilibrium
Hardy and Weidnberg
2. Gene Flow
-few populations are isolated- there are individuals moving in and out of a population
-the random immigration and emigration of individuals increases genetic variation within a
population and reduces differences between populations
37
3. Non-random mating
-organisms usually mate with individuals in close proximity.
-there may also be selectivity among mates (strongest/fastest/brightest colours
etc)
-this may lead to inbreeding, which could lead to a change in allelic proportions
favouring individuals that are homologous for particular traits
4. Mutation
-a gene mutation is a RANDOM insertion, deletion or substitution of bases
in the DNA code
-a chromosomal mutation is a deletion, duplication, inversion, or
translocation of an entire chunk of a chromosome
-mutations are usually harmful, but if beneficial, a mutation may lead to a
change in allelic frequencies
5. Natural Selection
-acts to select the individuals that are best adapted for survival and
reproduction
-acts on an organisms phenotype (visible physical traits) and changes allelic frequencies
-can occur through stabilizing selection, directional selection, and disruptive selection
-a fourth type, called sexual selection, is also considered a type of natural selection
Key terms:
selectivity
beneficial
moving
increases
adapted
frequencies
gene
isolated
Chromosomal
proximity
inbreeding
reduces
phenotype
38
Section 3.7 MODELS OF EVOLUTION
-Gradualism and punctuated equilibrium are two ways in which the evolution of a species can
occur.
-A species can evolve by only one of these, or by both.
-Scientists think that species with a shorter evolution evolved mostly by punctuated
equilibrium, and those with a longer evolution evolved mostly by gradualism.
1. Gradualism
 Slow change over time with no rapid periods
 Continuous series of small mutations
 Intermediary forms showing gradual change
 Can take a long time
2. Punctuated Equilibrium
 Rapid change interspersed with long periods of no change
 Fewer, bigger mutations
 No intermediary forms
Questions
1. Bacteria are prokaryotic cells with relatively small genomes that can reproduce in as
little as 20 minutes under favourable conditions. Suppose a bacterium had a mutation
that made it resistant to an antibiotic drug. What model of evolution does this
demonstrate?
2. Give an example of evolution that demonstrates gradualism.
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Keywords
longer
both
ways
rapid
small
Long time
shorter
no
intermediary
No rapid
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Section 3.8 DIFFERENT PATTERNS OF EVOLUTION
Factors such as environment and predation pressures can have different effects on the ways in
which species exposed to them evolve. As a result, evolution over time can follow several
different patterns. These include three main types of evolution: divergent, convergent, and
parallel evolution.
1. Divergent Evolution (see “A”)
 occurs when one species diverges into multiple
descendant species.
 Darwin's finches are an example of this.
 Aka adaptive radiation
2. Convergent Evolution (see “B”)
 occurs when species have different ancestral origins
but have developed similar features.
 Example: sharks and porpoises (dolphins too!)
3. Parallel Evolution (see “C”)
 Occurs when species have a common ancestor and
develop similar features
 Example: Wooly Mammoth and modern elephant
Another pattern observed is Coevolution. Coevolution occurs when two species influence each
other during evolution. For example, an insect may evolve specialized parts that allow it to feed
on a specific flower, whereas the flower evolves to facilitate pollination by that particular
insect.
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Keywords
parallel
B
divergent
coevolution
adaptive
ways
C
convergent
patterns
similar
influence
different
A
Section 4: Artificial Selection and Genetic Modifications




In the past, humans
developed the skills
to selectively breed
plants and animals to
suit their needs.
The gray wolf, for
example, was bread
to assist humans with
herding animals,
hunting, and for
companionship.
This human-lead
process of selective
breeding is called
artificial selection.
Artificial selection of the gray wolf ultimately lead to the development of the many
breeds of dogs that exist today.
Artificial selection differs from natural selection in several ways:
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One the ethical concern for artificial selection is that organism are modified for human gain
rather than to the benefit of the species. Bull dogs, for example, have been bred to have such
large heads that pregnant bull dogs often need caesarians to be able to give birth successfully.
Keywords
artificial
benefit
dogs
selectively
companionship
caesarians
gain
natural
Recently, scientists have developed the technology to isolate and modify the genetic code of
life, DNA.
This has enabled them to develop genetically modified organisms.
The process of building a genetically modified organism are as follows:
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What are some of the Uses for Genetic Engineering?
Grow human hormones in bacteria cultures
Make artificial sweeteners using bacteria
Study human diseases by inserting human DNA into mice
Replace incorrect DNA sequences and cure genetic diseases
Replace harmful bacteria on plants with non-harmful bacteria
Use nitrogen bacteria in the soil & plants to make fertilizer
Improve transport of fruits by extending the time it takes for them to ripen
Create plants and animals that are resistant to diseases
Increase protein production of cells ex. Insulin for diabetics
Assist in human reproduction by fixing broken genes in the egg/sperm
Assist in human organ transplants by reducing rejection of the organ by the host
What are some concerns around Genetic Engineering?
Introduced genes may escape into non-modified organisms ex. Cross pollination of GM plants
with non-GM plants
Pesticide resistant crops may cause excessive use of pesticides
People with allergies may inadvertently be exposed ex. Eat a tomato with a peanut gene
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Section 5: Trends in Complexity
As we continue learning in this course, we will be taking a closer look at trends in complexity in
the evolution of life. In particular, we will focus on the following.








Body transport
o How do organisms transport materials inside the body?
o Diffusion? Osmosis? Transport vessels?
Gas exchange
o How do organisms obtain oxygen?
o How do organisms release carbon dioxide?
o How does this process change as organisms move from water to land
and become larger?
Cephalization
o Why is the development of a head so important?
o What advantages does having a brain bring to the table?
Reproduction
o What form is used? Asexual? Sexual? Both?
o How does this connect to the type of environment lived in by the
organism?
Symmetry
o Radial? Bilateral? Non-uniform?
o How does symmetry connect to the type of environment lived in by the
organism?
o How does symmetry affect mobility?
Coelom
o Does the organism have a coelom? Pseudocoelom? None?
o Why is the coelom so important?
Tissue development
o Does the organism have tissue? How many layers?
Vascularization
o Does the organism have a blood vessel syste
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