What is the correct definition of the term systemic circulation?
a. a yellowish fluid, the watery portion of blood.
b. circulation that carries the blood from the heart, through the lungs, and back to the heart.
c. circulation that sends oxygen-rich blood to all the body tissues except the lungs.
d. the force of blood pushing against the walls of the blood vessels.

Which element is found in both dna and proteins

New york city has 2,181 inhabitants per square mile. the state of alaska has 1.03 inhabitants per square mile. ecologists would say alaska has a low exponential growth population density birth rate carrying capacity

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.