Which statement is true with respect to protonema?
it gives rise to sporophyte.
it produces male gametes.
it gives rise to gametophyte.

An example of internal feedback working to maintain homeostasis is your a. decreased respiration rate when you are studying b. decreased heart rate when you are sad c. increased respiration rate when your muscles need more oxygen d. increased heart rate when your lungs need more oxygen

Cells destroy body cells infected by a virus or bacteria. killer t t memory t none of the above

The vaccine in a flu shot contains weakened flu viruses. how does a flu shot work with the immune system? a. it destroys lymphocytes. b. it destroys macrophages. c. it activates macrophages. d. it activates lymphocytes.