Assertion and reason

Exercise and reference answers

Questions

1. Reason

   Without differences in fitness there is nothing to select between.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Natural selection needs variation to act on.

2. Reason

   Genetic drift operates independently of fitness.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Small isolated populations can change by chance alone.

3. Reason

   Chemical evolution formed biomolecules first.

   Verdict

   The assertion is false and the reason is true.

   Assertion

   Life appeared before any biomolecules existed.

Explanation