What is released by an excited presynaptic neuron and then diffuses across the synaptic cleft?
A. A neurotransmitter
B. Electrons
C. Potassium ions
D. Sodium ions
Answer: A
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Atoms composed of the same numbers of protons and electrons, but different numbers of neutrons, are called
a. isomers. b. ions. c. isotopes. d. organic atoms.
The connective tissue that is found in the tendons is:
a. mesenchyme b. reticular c. dense regular d. dense irregular
Which of the following statements regarding neural regulation of gastrointestinal function is TRUE?
A. Networks of neurons in the wall of the GI tract innervate the wall's smooth muscle. B. Smooth muscle of the GI tract is innervated by both sympathetic and somatic motor nerves. C. If the autonomic nerves to the GI tract were cut, digestion and absorption of food could no longer take place. D. The nerve plexus of the GI tract exists in a single layer, just outside of the serosa. E. There are no afferent neuronal pathways from the GI tract to the central nervous system.
What is the correct order for the vertebral regions, from superior to inferior?
A. Thoracic - cervical - lumbar - coccygeal - sacral B. Cervical - thoracic - sacral - coccygeal - lumbar C. Thoracic - sacral - lumbar - cervical - coccygeal D. Cervical - thoracic - lumbar - sacral - coccygeal E. Thoracic - coccygeal - cervical - lumbar - sacral