Which type of anatomic structure are bird wings and butterfly wings when compared to each other?
a. vestigial
b. homologous
c. analogous
d. heterologous

Which of the following is a difference between active transport and facilitated diffusion? view available hint(s)which of the following is a difference between active transport and facilitated diffusion? facilitated diffusion can move solutes against a concentration gradient, and active transport cannot. active transport involves transport proteins, and facilitated diffusion does not. facilitated diffusion involves transport proteins, and active transport does not. active transport requires the expenditure of cellular energy, and facilitated diffusion does not.

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 do living things obtain phosphorus