Question 4 of 10 Which of these is not a function of some membrane proteins?
O A. Catalyzing chemical reactions in the cell
B. Receiving messages from other cells
C. Recognizing other types of cells
O D. Keeping polar molecules out of the cell

Adigestive system that is a series of tubes beginning at the mouth and ending at the anus is a digestive system.

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.

What does polymerase chain reaction (pcr) do? o a. separates dna fragments by size o b. cuts a dna sample into fragments o c. provides an overall picture of a person's chromosomes o d. makes more copies of a sample of dna