Choose all the answers that apply. The cell membrane . does not exist in plant cells
is made of phospholipids
is a single layer
is embedded with proteins
controls the transfer of materials into and out of the cell

The reactions that occur in the ribosome, where amino acids are combined to form proteins are anabolic or catabolic?

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.

Which of these is not a nucleotide base found in dna?