Eggs, sperm, urine and wastes all empty into what structure?

The energy of blowing wind can be harnessed to create electricity. why is wind considered a renewable energy source? a) wind does not cause destruction of the environment.b) wind turns the blades of a windmill that creates electricity.c) wind provides only a very small amount of electricity to the united states.d) wind comes from atmospheric conditions that are available indefinitely.

What is the name of the two satelites on mars

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.