Biology lecture 1

Question 1

Novel Allels

Answer 1

New version of genes created (Mutation)

Question 2

Individual Fitness depends on its environment. The same ______ (Physical expression of a gene) has different fitness in different environments.

Answer 2

Phenotype

Question 3

Can selection CREATE variation?

Answer 3

Selection can only be used for existing genes. It CANNOT CREATE variation

Question 4

Name the FOUR trade-offs/constraints in natural selection?

Answer 4

1) Constraint- previously selected event limits ability do do something else.
2) Trade-off- Cant do “blank” because you can do “Blank”
3) Physical constraints- nerve reception not fast enough,etc.
4) Genetic Variation-Selection can only choose pre-existing traits

Question 5

Define Adaption

Answer 5

Adaptions are inherited characteristics that enhance reproduction, survival in specific environments.

Question 6

Darwin developed his theory of evolution to understand…
1)
2)
3)

Answer 6

1) Diversity of life on earth
2) Ways organism are suited to their environments
3) Shared characteristics of different life-forms.

Question 7

What does the AGENT OF SELECTION do for phenotypes?

Answer 7

Selection determines which phenotypes succeed.

Question 8

What does the ENVIRONMENT do for selection of phenotypes?

Answer 8

Environments influence fitness of a particular phenotype.

Question 9

Darwin’s theory of descent with modification.

Why do different species have similar appearances.

Answer 9

Offspring resemble parents-Shared characteristics among groups of organism due to descent from common ancestor.

Question 10

In natural selection, what are FIVE sources of Variation?

Answer 10

1) Mutation
2) Gene Duplication
3) Sexual Reproduction
4) Error during Meiosis
5) Gene Flow

Question 11

What is GENE FLOW?

Answer 11

Gene Flow is the transfer of genes from one population to another.

Result of migration of a new species into/out of a population.

Question 12

Descent with modification

If more young are born than can survive?

Answer 12

If more born are young then can survive, they will compete for limited resources.

Question 13

Descent with modification

If there is unequal ability to survive and Reproduce then?

Answer 13

Unequal ability to survive and reproduce leads to accumulation of favorable traits among population over generations. Those with the better traits out produce those that don’t.

Question 14

Diversity is rich in species today. True/False

Answer 14

True

Question 15

Natural Selection requires THREE things

Answer 15

1) Individuals must VARY in characteristics
2) Variation must be HERITABLE
3) Individuals differ in RELATIVE FITNESS in a particular environment.