MOD 2 Test Questions

Question 1

Mutation

Answer 1

A random change in the DNA code that might change the resulting protein

E.g growing a third arm

Question 2

Gene

Answer 2

A code in the DNA that determines how a protein is built

E.g the trait of having blue eyes

Question 3

Allele

Answer 3

The code for one of several variations of the protein coded for by a gene (a single base or a segment of bases)

E.g brown eyes are the dominant version of the gene (allele) and blue eyes are the recessive version

Question 4

Mutation

Answer 4

A random change in the DNA code that might change the resulting protein

E.g growing a third arm

Question 5

Protein

Answer 5

A biological structure that determines how a cell is built and how it functions

Question 6

Evolution

Answer 6

The change in the genes of a population over time

E.g humans have evolved to be taller over generations

Question 7

To determine that the behaviour depicted on the left was shaped by natural selection (Mother bird feeding her baby birds food she caught), we must know that the trait is beneficial in the face of selective pressure in the environment.

Identify the selective pressure that would reduce the fitness of baby waxwing birds who did not exhibit this behaviour.

Explain why it functions as a selective pressure.

Answer 7

Starvation

Because the baby birds who don’t get fed starve to death, so they can’t grow up to reproduce and pass on their genes.

Question 8

To determine that the behaviour depicted on left (Mother bird feeding her baby birds food she caught) was shaped by natural selection, we must know that the trait has genetic variation in the population.

Describe what an unfavourable genetic variation in this behaviour might look like in this population.

Explain why that unfavourable genetic variation is probably the result of a new mutation rather than inherited from the parents.

Answer 8

The baby bird looks away from mom, doesn’t open its mouth,
etc:

If either parent had that trait, it would not have
lived to reproduce as it would have starved

Question 9

To determine that the behaviour depicted at left (Mother bird feeding her baby birds food she caught) was shaped by natural selection, we must know that the trait generates differential survival and reproduction in the population.

Explain why differential survival alone is insufficient to generate a natural selection.

Answer 9

Survivors who don’t reproduce and pass on their genes
do not contribute to making the next generation more
suitable to their environment/better adapted