An enzyme is a protein that-A. increases the rate of a chemical reaction b. transports nutrients across a membrane
C. provides structure for the cell's organelles
D. receives and sends signals across a cell

How does an angiosperm prevent self pollination

Which of the following statements about archaea and bacteria is true? a. neither is single-celled. b. they both have nuclear membranes. c. neither reproduces by binary fission. d. they both lack a nuclear membrane.

How long does it take a skateboarder going 6.0 m/s to come to a complete stop if she slows down at a rate of 2.0 m/s^2