Homeostasis - QA
Which of the following is a way in which the somatic and autonomic nervous systems are similar?
a) both systems have motor fibers
b) both systems send the same target organ responses to their neurotransmitters
c) both systems share common effectors
d) both systems share common efferent pathways
*both systems have motor fibers, but the somatic and autonomic nervous systems differ (1) in their effectors, (2) in their efferent pathways, and (3) to some degree in target organ responses to their neurotransmitters
For which activities is the parasympathetic nervous system generally responsible?
Resting and digesting.
*the parasympathetic division, sometimes called the "resting and digesting" system, keeps body energy use as low as possible
Which of the following is NOT an autonomic nervous system effector?
a) skeletal muscle
b) smooth muscle
c) cardiac muscle
*the somatic nervous system stimulates skeletal muscle, whereas the autonomic nervous system innervates cardiac muscle, smooth muscle, and glands
Which of the following is not a result of parasympathetic stimulation?
a) elimination of urine
c) increased peristalsis of the digestive viscera
d) dilation of the pupils
*parasympathetic stimulation is the "rest and digest" system
The ANS stimulates smooth and skeletal muscles and glands, whereas the somatic nervous system innervates cardiac muscles only.
Most blood vessels are innervated by the sympathetic division alone.
Autonomic ganglia are motor ganglia only.
Conduction through the autonomic efferent chain is faster than conduction in the somatic motor system.
*conduction through the autonomic efferent chain is slower than conduction in the somatic motor system
Which of the following best demonstrates an example of cooperation of the parasympathetic and sympathetic nervous systems?
a) sympathetic stimulation causes vasodilation of blood vessels in the clitoris, leading to erection; parasympathetic stimulation then causes reflex contractions of the vagina
b) parasympathetic stimulation causes vasodilation of blood vessels in the penis, leading to erection; sympathetic stimulation then causes ejaculation
c) parasympathetic stimulation causes copious sweating; sympathetic stimulation causes epidermal pores to dilate
d) sympathetic stimulation causes vasodilation of blood vessels in the penis, leading to erection; parasympathetic stimulation then causes ejaculation.
*the best example of cooperative ANS effects is seen in controls of the external genitalia [parasympathetic stimulation causes vasodilation of blood vessels in the external genitalia, and is responsible for erection of the male penis or female clitoris during sexual excitement] [sympathetic stimulation then causes ejaculation of semen by the penis or reflex contractions of the vagina]
Thermoregulatory responses to increased heat are mediated by the sympathetic nervous division.
The stimuli causing endocrine glands to secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients are called:
a) humoral stimuli
b) endocrinal stimuli
c) hormonal stimuli
d) neural stimuli
*humoral stimuli [are endocrine glands that secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients], hormonal stimuli [are also bloodborne chemicals]
Which of the following hormones stimulates the adrenal cortex to release glucocorticoids that help the body to resist stressors?
b) thyroid-stimulating hormone
c) follicle-stimulating hormone
d) adrenocorticotropic hormone
*adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to release corticosteroid hormones, most importantly glucocorticoids that help the body to resist stressors
Which gland is found atop the kidneys?
*the paired adrenal glands are pyramid-shaped organs perched atop the kidneys, where they are enclosed in a fibrous capsule and a cushion of fat
What is required for the production of anterior pituitary gland hormones?
a) humoral stimuli
b) neural stimuli (from the sympathetic division of the ANS)
c) hormonal stimuli
d) all of these
* the anterior pituitary gland requires specific regulating hormones produced by the hypothalamus to stimulate its cells to produce hormones
Several hormones are synthesized in the hypothalamus and transported to the anterior pituitary gland. The mechanism of transportation from hypothalamus to anterior pituitary gland is through the:
a) general circulatory system
b) hepatic portal system
c) hypophyseal portal system
d) feedback loop
The neurohypophysis or posterior lobe of the pituitary gland is not a true endocrine gland because:
a) it is unable to function as an endocrine tissue because it is actually part of the neural system due to its location
b) embryonically it was an endocrine tissue, but in the adult human it is no longer functional
c) it is strictly a part of the neural system and has little or nothing to do with hormonal release
d) it is only a hormone storage area that receives hormones from the hypothalamus for release