Which statement about precapillary sphincters is CORRECT?
A. They contract when oxygen levels in the tissue are low.
B. They can close off the capillaries by contracting.
C. They are openings that allow large molecules and blood cells to leave the capillary.
D. When the precapillary sphincters are open, blood flows only through the thoroughfare channels.
E. They are voluntary.
B
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Stimulation of the Golgi tendon organs result in which of the following changes in the reflex arc?
A. stimulation of a stimulatory association neuron B. stimulation of an inhibitory neuron C. decreased action potentials in alpha motor neurons D. contraction of skeletal muscle fibers E. stimulation of an inhibitory neuron and decreased action potentials in alpha motor neurons
The membranes that line the cavities of freely movable joints are referred to as ________.
A. mucous membranes B. synovial membranes C. cutaneous membranes D. serous membranes
One of the important functions of muscle in the body is the regulation of blood glucose.
Answer the following statement true (T) or false (F)
All of the following are muscles of the arm or forearm except which one?
A. Deltoid B. Erector spinae C. Brachialis D. Extensor carpi ulnaris