amitvocational2001

Why is RNA necessary to act as a messenger? Why can't the code be taken directly from the DNA? How do some cells become brain cells and others become skin cells, when the DNA in ALL the cells is exactly the same? In other words, if the instructions are exactly the same, how does one cell become a brain cell and another a skin cell?

DNA: ...3' A C C A A G T C T 5'...

The strand of DNA used above undergoes a mutation, such that the second C from the 3' end is changed to a T. What would change in the polypeptide?

Listed below are a serious of disorders that are caused by a vitamin deficiency. What vitamin is missing in each disorder, and what are two or three of the presenting symptoms?

a.) Scurvy

b.) Multiple carboxylase deficiency. (Can also be caused by a missing enzyme)

c.) Pernicious anemia

d.) Megaloblastic anemia

e.) Pellagra

f.) Ariboflavinosis

g.) Wernicke-Korsakoff syndrome

A nerve impulse is

1. Two persons with the sickle cell trait marry and want to have children, but concerned about them having sickle cell anemia. What is the probability of sickle cell anemia in their children? What proportion of their children would you expect to be carriers?

2. If a person with the sickle cell trait marries a person with a normal hemoglobin, what is the probability they will have a child with sickle cell anemia? What proportion of their children would you expect to be carriers?

A person without the allele for sickle cell anemia has children with a person who is a carrier for sickle cell anemia but doesn’t have the disease. What percentage of their children will have sickle cell anemia? What percentage of their children will be carriers for sickle cell anemia? Show your work with a Punnett square. You can copy/paste the blank table below or create a table in the submission box to complete the Punnett square.