Biology · Unit 7 · Paper 2

Natural Selection unit test

A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.

Paper 1 Paper 2 Paper 3

Each paper is built from this unit’s 38 terms and is the same for everyone, so a teacher can assign “Unit 7, Paper 2” and every student sits the identical test. Multiple choice is marked objectively; the written sections you mark yourself against the model answer and rubric.

Suggested time 36 min 33 points0/17 attempted

Stabilizing selection

Hardy-Weinberg equations

Convergent evolution

Frequency-dependent selection

Sexual selection

Heritability requirement

Adaptive radiation

Artificial selection

Variation as the raw material

Antibiotic and pesticide resistance

Mass extinction and its effects

Phylogenetic tree

Short answer 1. Define or explain: Speciation

3 pts

Short answer 2. Define or explain: Gene flow

3 pts

Short answer 3. Define or explain: Natural selection

3 pts

Short answer 4. Define or explain: Molecular clock

3 pts

Free response

9 pts

In a beetle population, dark body color (D) is dominant to light body color (d). Among a random sample of 1,000 beetles, 360 are light-colored.

Calculate the frequencies of the D and d alleles, showing your work.

Calculate the expected numbers of homozygous dominant and heterozygous beetles in the sample.

State two conditions that must hold for a population to remain in Hardy–Weinberg equilibrium.

After ten generations on a dark volcanic substrate with heavy bird predation, only 90 of 1,000 beetles are light-colored. Calculate the new frequency of the d allele and identify the mode of selection acting on the population.

Explain why the d allele is unlikely to be eliminated from the population entirely.