Draw a diagram of the cerebral motor cortex and descending input to spinal motor neurons. Voluntary suppression of the knee jerk reflex originates in the motor cortex, which can send inhibitory signals to the motor neurons. If the left motor cortex is active, is the left or right knee jerk reflex suppressed or are both suppressed? Explain your answer. If the left side of the spinal cord at the
level of leg muscle control is damaged, is it the left or right knee jerk reflex that is suppressed or are both suppressed?
What will be an ideal response?
The diagram should resemble Figure 13.11 in the chapter. The left motor cortex controls the right spinal motor neurons and therefore the right knee reflex. The left side of the spinal cord controls the reflex on the left side.
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Indicate whether the statement is true or false.
Liz is 5 weeks pregnant. During an ultrasound of her ovaries, which of the following can be seen?
A. No follicles B. One large corpus luteum and no other follicles beyond primordial stage C. No follicles beyond primordial follicle stage D. 10-25 mature follicles E. Several follicles in primordial, primary, and preantral stages and one corpus luteum
A difference between mucous membranes and serous membranes is
A) whether the cavity is open to the exterior or not. B) the amount of blood vessels lining the cavity wall. C) whether the tissue is epithelial or connective. D) the density of collagen fibers in the cavity wall. E) whether the membrane is thick or thin.
Micturition involves both ________ and ________ nerve signals.
A. sympathetic; parasympathetic B. somatic; enteric C. sympathetic; somatic D. somatic; parasympathetic