What organelle converts food into a form of chemical energy the cells can use in chemical reactions? A) endoplasmic reticulum
B) mitochondria
C) chloroplasts
D) nucleus

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.

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

The same agricultural practices are used in every country of the world. select the best answer from the choices provided t f