The parasympathetic nervous system decreases heart rate by:
A. releasing norepinephrine.
B. opening sodium gates.
C. closing sodium gates.
D. opening potassium gates.
Answer: D. opening potassium gates.
You might also like to view...
A cell duplicates its chromosomes during the ________ phase
A) Go B) G1 C) G2 D) Gm E) S
Which of the following effect the rate of gas exchange?
a. partial pressure gradient b. surface area for exchange c. diffusion distance d. solubility of the gas e. all of the above
What is the best explanation for the observation that mitosis occurs in the deepest layers of the epidermis?
A. Cells are dead in the top layer of the skin. B. Protein granules accumulate in the cytoplasm of cells as they move up the layers. C. Mitosis requires oxygen and nutrients supplied by blood vessels. D. Cells undergo apoptosis in upper layers of the epidermis. E. The cells in the deepest layer of the epidermis are metabolically active.
This is the site of protein synthesis in the cell
A) Ribosomes B) Mitochondria C) Lysosomes D) Golgi apparatus