Skeletal muscle contraction is stimulated by the neurotransmitter ______, which is released by nerves at the neuromuscular junction
a) acetylcholine
b) nitric oxide
c) dopamine
d) glycine
Ans: a) acetylcholine
You might also like to view...
You might infer from packages of commercial fertilizer that which of the following nutrients are most limiting to plant growth?
a. Carbon, nitrogen and phosphorous. b. Nitrogen, phosphorous and potassium. c. Hydrogen, phosphorus and magnesium. d. Iron, Magnesium and nitrogen. e. Phosphorus, potassium, and calcium.
The smooth endoplasmic reticulum
a. is the site where lipids destined for other cellular compartments are manufactured. b. produces the energy needed to run chemical reactions in the cell. c. converts sunlight into chemical energy. d. stores water, nutrients, and enzymes.
How do DNA repair enzymes typically find mismatched base pairs?
a. by scanning for Okazaki fragments b. by scanning for distortions in the newly synthesized chain c. by scanning for missing hydrogen bonds d. by scanning for unsealed nicks in the DNA strands
An _______________ cannot survive in the presence of oxygen.
A. Obligate Aerobe B. Facultative Aerobe C. Facultative Anaerobe D. Obligate Anaerobe