In the disease myasthenia gravis, there is a deficiency of acetylcholine receptors at the neuromuscular junction. This shortage blocks contraction by preventing
A. generation of action potentials in the muscle fiber.
B. the interaction of troponin with tropomyosin.
C. release of Ca2+ from the sarcoplasmic reticulum.
D. opening of the T-tubule system.
E. generation of action potentials in the motor neuron.
Answer: A
You might also like to view...
In a stream that flows over limestone you would predict there would be higher
A) solute concentrations. B) temperatures. C) flows. D) biodiversity.
How many chromosomes do Klinefelter and Turner syndromes have, respectively?
What will be an ideal response?
Which enzyme speeds up the formation of carbonic acid from carbon dioxide and water?
A) cyclo-oxygenase B) hydrogenase C) carboxylase D) carbonic anhydrase
Which of the following statements correctly describes a portion of the pine life cycle?
A) Female gametophytes use mitosis to produce eggs. B) Seeds are produced in pollen-producing cones. C) Pollen grains contain female gametophytes. D) A pollen tube slowly digests its way through the triploid endosperm.