How is it that norepinephrine (NE) can inhibit smooth muscle action in airways, yet stimulate contractions in smooth muscles everywhere else in the body?
What will be an ideal response?
Airway passages have smooth muscle cells that are unique in that they have two receptor sites on their outer membrane. One receptor site accepts ACh as the neurotransmitter. When excited it causes the smooth muscle to contract. The second site accepts NE and the inhibitory effect is that the ACh dilates the airway.
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An example of keratinized stratified squamous epithelium would be
A) exposed skin. B) air sacs of the lungs. C) the lining of the anus. D) the outer covering of the intestines. E) the lining of the oral cavity.
Curare blocks neuromuscular transmission by preventing the release of neurotransmitters from the motor neuron
Indicate whether the statement is true or false.
How could you best improve the contrast of this specimen?
What will be an ideal response?
The skull contains ________ bones
A) 32 B) 22 C) 42 D) 12 E) None of the answers is correct.