Question

for questions 14 - 20, fill in the blanks using the word bank below. fitness evolution meiosis variation mutations selected competition pressure allele frequency 14. according to darwins theory of natural selection, every population has heritable __ in their traits. 15. these differences are caused by meiosis and . 16. predators, competition, changing environments will exert on individuals in a population. 17. some traits will be beneficial and increase an organisms . 18. eventually favorable traits will be for, while harmful traits will not. 19. this will cause a shift in the of a population over time. 20. this shift in the genotypes and phenotypes of a population is known as __.

Explanation:

1. Darwin's natural - selection theory is based on heritable variation in traits.
2. Meiosis and mutations cause genetic differences.
3. Predators, competition, and changing environments are selection pressures.
4. Beneficial traits increase an organism's fitness.
5. Favorable traits are selected for.
6. Natural selection causes a shift in allele frequency.
7. A shift in genotypes and phenotypes over time is evolution.

Answer:

1. variation
2. Mutations
3. pressure
4. Fitness
5. Selected
6. allele frequency
7. Evolution