Transcript MP4 Quarterly Review

MP4 Quarterly Review
By: Mrs. Tokmajian & Mrs. Jackson
1. Define genetic drift: Change in allele frequencies due
to chance
Define both types of g.d. and give examples:
Bottleneck Effect: Random event decreases population and
genetic variation in population. Ex.: Overhunting of
elephant seals
Founder Effect: Individuals leave old population and start
new population with decreased genetic variation. Ex.: Owl
Island
2. Define gene flow
Exchange or transfer of alleles/genetic
information between populations
3. Define natural selection. How
does it affect species diversity?
-Organisms with traits that make them wellsuited to their environment are more likely to
survive, reproduce, and pass their beneficial
traits on to the next generation.
-Natural selection increases species diversity
(led to 2 types of tortoises on diff. islands those with long necks/legs, those with short
necks/legs)
4. Explain how environment can cause a shift in the phenotype of a
species (think of the black and white pocket mice in the desert).
-Environment can cause an increase in the
number of individuals with beneficial
phenotypes and a decrease of individuals
without beneficial phenotypes.
-Black pocket mice increased due to phenotype
helping them blend in with new dark
environment from black hardened lava rock
while white mice decreased.
5. What are the sources of genetic
variation in a population?
-Mutations
-Combination of gametes formed by meiosis
during sexual reproduction
6. Which produces more genetic variation:
sexual or asexual reproduction?
Sexual reproduction. Asexual reproduction
produces genetically identical offspring with NO
variation.
7. What is reproductive isolation?
What does it lead to?
When two populations of a species can no
longer successfully mate - leads to speciation.
7. (continued) 3 isolating
mechanisms...
-Behavioral isolation: differences in courtship or mating
behaviors.
-Geographic isolation: physical barriers that divide a
population into two or more groups.
-Temporal isolation: timing prevents reproduction between
populations.
8. What type of selection favors phenotypes at both
extremes and selects against intermediate phenotypes?
Disruptive selection
Selection FOR brown and
blue, AGAINST
intermediate (brownish
bluish)
9. What type of selection favors phenotypes at only one
extreme?
Directional selection
10. What type of selection favors intermediate phenotypes
and selects against extreme phenotypes?
Stabilizing
11. DNA & proteins can be used to determine evolutionary relationships. 3 different species have a similar
protein. Explain how you could tell which 2 species are less closely related by looking at the protein.
Compare the amino acid sequences of the proteins - species with more differences are less closely related
12. Explain embryology and how it
shows evidence of evolution
Embryology compares similarities in
developmental stages of different organisms to
provide evidence that they share a common
ancestor.
Embryo
Fetus
13. Explain what vestigial structures are and what they
tell us about evolution (think of wings on flightless
birds).
Structures that had a function in an ancestor
but don’t in modern day organisms.
Ex.: Wings on flightless birds show they
evolved from ancestors that flew. They’ve since
evolved adaptations to travel efficiently in other
ways.
14. Explain what homologous structures are and how they provide
evidence for evolution
Homologous structures are structures in
different organisms that share similar structures
but perform different functions - provides
evidence of a common ancestor. Ex.: forelimbs
of humans and cats.
HONORS: What is required for
natural selection to occur?
-Variation
-Overpopulation
-Adaptation
-Descent with modification
(VOAD)
Ecology
1. The 5 levels of ecology in order are listed below. Next to
each category name, write the biotic or abiotic factor
that belongs with each level.
1. Organism: Alligator
2. Population: 5 Alligators
3. Community: Alligators, Birds, Grass, Frogs, Trees
4. Ecosystem: Alligators, Birds, Grass, Frogs, Trees, Soil, Water, Sunlight
5. Biome: Temperate Deciduous Forest
Ecology
2. Bacteria plays a major role in nitrogen fixation in the nitrogen cycle.
Bacteria in the soil and in plant roots fixing the nitrogen into ammonia
so that plants can readily use it. How does nitrogen get into the soil so
that bacteria can use it?
Answer: Besides fixation of
atmospheric nitrogen,
decomposers break down
dead plants and animals.
This process returns nitrogen
to the soil so that bacteria can fix it
for plants.
*Also returned through animal urine
(not shown on diagram)
Ecology
3. How is the carbon cycle related to the oxygen cycle?
Answer: In the carbon cycle, plants take
in carbon. Plants receive this carbon
in the form of carbon dioxide from the
process of photosynthesis.
Remember: CO2 + H2O + light
(all inputs of photosynthesis)
Ecology
4. Draw a food chain and a food web and explain the similarities and
differences between them. A.: Food web = many connected food chains
Food Web
Food Chain
Ecology
Question 4 Continued:
Similarity: A food web contains multiple related food chains. (Both
show feeding relationships)
Difference: Food chains show one feeding relationship, food webs
show multiple feeding relationships.
Ecology
5. Symbiotic relationships between organisms are relationships where
the 2 organisms have close interactions with each other usually in a
positive way. Name and explain the 3 types of symbiotic relationships.
A. Mutualism: Both organisms benefit from the relationship. Ex: bee
and flower
B. Commensalism: One organism benefits and the other is neither
helped nor harmed. Ex: clownfish and sea anemone
C. Parasitism: One organism benefits from the relationship while the
other is harmed. Ex: tick and human
Ecology
6. Define the terms Biotic and Abiotic and give
examples.
A. BIOTIC: Living (animals, plants, etc)
B. ABIOTIC: Non-Living (water, light, soil,)
Ecology
7. According to this food web, if the grasshoppers were removed, how
would the other organisms be affected?
Answer: Most obvious answer is that
lizards and hawks would go down.
*Which populations would be affected
if grass was removed?
ALL OF THEM
Ecology
8. Give an example of competition between two organisms and
predation between two organisms.
Answer:
Competition: 2 male lions fight for a female, or for food. 2 species of
plants fight for the same sunlight and soil.
Predation: A fox hunts, kills, and eats a rabbit.
Ecology
9. Use the graph to determine when this population reached its carrying
capacity?
Answer: Approximately on Day 22
Ecology
10. According to the diagram, if lizards were
removed, what would happen to the locusts
and the snakes?
Answer: Snakes would DECREASE because they have nothing
to eat. Locusts would INCREASE because nothing is eating
them. *Ecosystem thrown off balance
Ecology
11. Using your knowledge of renewable
resources from class, explain 2 ways in which
humans can reduce the waste/pollution
produced on Earth.
Answer: Reduce CO2 emissions to cut back
on global warming, use renewable energy like
solar energy to cut back on burning fossil fuels
like oil and gas. Recycle to cut down on
waste,etc.
Ecology
12. Give 2 reasons why invasive/non-native
species can be harmful to a new area.
Answer: They have no natural predators so
they can easily take over a new area. They
take space and food away from the native
species that lives there.
BONUS: What is biodiversity?
Variety of living things – different species live in
different environments