In humans, albinism (unpigmented skin, hair, and eyes) is due to an enzymatic deficiency, and it is an autosomal recessive trait. Suppose that in a small country of one million people (“Generation 1”), there are 500 aa albinos and 9000 Aa heterozygous carriers. What is the probability that a child will be albino if: Both parents are members of Generation 2, and one parent is albino and the other is non-albino.

#Question id: 3826

#Unit 3. Fundamental Processes

Which scientists first gave experimental evidence that DNA is the genetic material?

#Question id: 3827

#Unit 3. Fundamental Processes

It takes about the same amount of time for eukaryotic chromosomes to be replicated in vivo as it does for E. coli. Why is this true?

#Question id: 3828

#Unit 3. Fundamental Processes

Why does E. coli need both DNA polymerase III and DNA polymerase I?

#Question id: 3829

#Unit 3. Fundamental Processes

Why is only one copy of DNA made per cell division cycle in eukaryotes despite the presence of multiple origins of replication?

#Question id: 3830

#Unit 3. Fundamental Processes

Why is DNA damage in skin cells from exposure to excessive UV light not completely reversed by photoreactivation?

#Question id: 3831

#Unit 3. Fundamental Processes

State whether the following statements is true/false regarding DNA replication.

1. In E. coli replication begins at the origin of replication and proceeds in one direction until the entire circular DNA molecule has been copied.

2. The chromosome of the fruit fly (D. melanogaster) is about twice as large as the E. coli chromosome.

3. Prokaryotic DNA replication occurs in two steps. First, ATP provides a phosphate to the growing DNA chain. This is followed by addition of a nucleoside.

4. DNA polymerase III is the largest DNA polymerase in E. coli.

5. The β subunits of E. coli DNA polymerase form a sliding clamp that surrounds the DNA strands at the replication fork.