Which of the followings are true of human genomic libraries? (Two correct answers).

A. They contain DNA copies of the mRNAs present in a particular cell or tissue.

B. They contain the equivalent of the entire human genome, cloned into a vector.

C. The use of the enzyme reverse transcriptase is crucial in their construction.

D. They are likely to contain sequences derived from introns.

Which is an advantage of having memory cells when a pathogen is encountered for a second time. a) the memory cells are what proliferate into clones of cells in response to the binding of an antigen. b) memory cells are vital to the primary immune response in that they immediately recognize pathogens even at the first encounter. c) memory cells are essentially effector cells that are short lived and attack antigens even without having a receptor specific to that antigen. d) it ensures that more lymphocytes with a receptor specific to a particular antigen will be present than in a host that had never encountered that pathogen.

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes

Give two examples of what would occur if one of the pairs did not match or had an extra chromosomes. explain how this might occur, and if it would be dangerous to the individual. fast.