1. Cystic fibrosis is the most common serious genetic disease in the USA. If the frequency, q, of the recessive cystic fibrosis allele, c, in the USA is 0.04, what is the frequency of people with cystic fibrosis? Remember that if C is the normal allele with a frequency p, then p + q = 1 and and the frequencies of the homozygous dominant, heterozygous and homozygous recessive genotypes are p2, 2pq and q2 respectively.
2. Explain the difference between homologous and analogous structures in animals or plants and describe what each tells us about the relatedness of the species involved.
3. Explain how the impact of a large meteor or asteroid colliding with the earth could have caused the Cretaceous extinction 65 million years ago. What is the evidence for such a collision?
4. Describe the four stages in the in the four stage hypothesis for the origin of life. Why is RNA a likely candidate for the original self-replicating molecule?