Compare and contrast the various types of autonomic receptors
What will be an ideal response?
Nicotinic and muscarinic receptors both bind acetylcholine. Nicotinic receptors are always excitatory and are located on all postganglionic cell bodies and the adrenal medulla. Muscarinic receptors can be excitatory or inhibitory and are located on cardiac and smooth muscle and glands. Alpha and beta receptors bind norepinephrine or epinephrine. Alpha-1 receptors are located on most target tissues and are excitatory. Alpha-2 receptors are found on digestive organs and are inhibitory. Beta-1 receptors are found on the heart and are always excitatory. Beta-2 receptors are found on arterioles and bronchioles and are inhibitory. The alpha receptors have a higher affinity for norepinephrine over epinephrine. Beta-1 receptors bind norepinephrine equally to epinephrine. Beta-2 receptors bind only epinephrine.
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In electrocardiography, a lead is a(n)
A) cable that attaches between the ECG machine and the body. B) electrode. C) pair of electrodes.
A joint with articulating surfaces that are nearly flat is a ________ joint.
Fill in the blank(s) with the appropriate word(s).
Which is true regarding the mediated transport of a substance across a plasma membrane?
A. It depends upon the binding of that substance to a specific site on the membrane protein. B. It depends upon movement of proteins from one side of the membrane to the other. C. It always increases in direct proportion to the increasing concentration of the substance on one side of the membrane. D. Both "depends upon the binding of that substance to a specific site on the membrane protein" and "depends upon movement of proteins from one side of the membrane to the other" are correct. E. All of the choices are correct.
Which is not a tropic hormone?
A. Prolactin B. Adrenocorticotropic hormone C. Follicle-stimulating hormone D. Thyroid-stimulating hormone