Unit 7: Natural Selection
Biology · Unit 7 · Paper 3

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 1Paper 2Paper 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 3” 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 31 min 28 points0/17 attempted
1

Cladogram and shared derived characters

2

Hardy-Weinberg equations

3

Hardy-Weinberg conditions

4

Lab: Artificial Selection

5

Allopatric vs sympatric speciation

6

Genetic drift

7

Fitness

8

Gene flow

9

Bottleneck effect

10

Variation as the raw material

11

Reproductive isolation

12

Mutation as the ultimate source of alleles

Short answer 1. Define or explain: Endosymbiosis as evolutionary evidence

3 pts

Short answer 2. Define or explain: Convergent evolution

3 pts

Short answer 3. Define or explain: Molecular clock

3 pts

Short answer 4. Define or explain: Natural selection

3 pts

Free response

4 pts

Two populations of a fish species become separated when a river changes course. After many generations, individuals from the two populations can no longer produce fertile offspring.

Identify the type of speciation described.

Explain how the geographic barrier contributed to divergence.

Identify whether the isolating mechanism described is prezygotic or postzygotic, and justify your answer.