Exam 2
The autonomic nervous system carries out many somatic reflexes that are crucial to homeostasis
false
Under normal circumstances, both divisions of the autonomic nervous system are active simultaneously
true
The autonomic nervous system is composed of ganglia in the central nervous system and ganglia in the periphery
false
Most autonomic efferent pathways involve one neuron
false
the parasympathetic division stimulates digestion
true
most preganglionic fibers synaps with postganglionic fibers in the dorsal root ganglia
false
all preganglionic fibers of the ANS pass through the sympathetic chain of ganglia, synapsing at least once there
false
the adrenal medulla is a modified sympathetic ganglia
true
fibers of the vagus nerve end very near or within their target organs
true
the autonomic effect on a target cell depends only on the neurotransmitter reaching that target cell
false
all sympathetic postganglionic adrenergic fibers secrete adrenaline
false
acrtylcholing (ACh) binds to both muscarinic and nicotinic receptors
true
acetylcholine (ACh) always has an excitatory effect
false
binding of norepinephrine (NE) to an alpha-adrenergic receptor is usually excitatory, and binding to a beta-adrenergic receptor is usually inhibitory
true
all autonomic output originates in the central nervous system
true
The autonomic nervous system controls all of the following except the __________.
skeletal muscle in the rectus abdominis
Autonomic nervous system fibers are involved in all of the following except __________.
maintaining tonicity of the muscles of the neck
Which one of the following best describes the order of a visceral reflex?
Sensory receptor → afferent nerve fiber → interneuron → efferent nerve fiber → gland
Which of the following statements is true regarding parasympathetic tone?
It holds the resting heart rate below its intrinsic rate.
Sympathetic nerve fibers are not associated with situations involving __________.
digestion
The background rate of sympathetic and parasympathetic activity is called ___________.
autonomic tone
The neurotransmitter(s) associated with autonomic ganglia is(are) __________.
acetylcholine (ACh)
The effect of autonomic fibers on target cells is _________. The effect of somatic fibers on target cells is __________.
excitatory or inhibitory; always excitatory
Which of the following is true regarding the autonomic nervous system?
Its denervation would cause hypersensitivity.
In response to high blood pressure, stretch receptors called __________ in the walls of arteries carrying blood to the head, will trigger a reflex that causes the heart to __________ its beats per minute.
baroreceptors; decrease
The motor pathway of the autonomic nervous system usually involves __________ neurons.
two
Preganglionic fibers run from the _________ to the __________.
gray matter; autonomic ganglia
Preganglionic fibers of the autonomic efferent pathway are _________ and secrete __________.
myelinated; acetylcholine (ACh)
Which of the following is not a reason that somatic reflexes act faster than visceral reflexes?
The effector organs in the somatic reflex are closer to the spinal cord.
Most fibers of the parasympathetic nervous system travel in the __________.
vagus
Sympathetic fibers arise only from the __________ region(s) of the
thoracic and lumbar
The sympathetic chain of ganglia is found at the __________ levels of the spinal cord.
cervical, thoracic, lumbar, sacral, and coccygeal
Which of the following is not a feature of the sympathetic division of the ANS?
It has long preganglionic fibers.
Which of the following is not a characteristic of the parasympathetic division of the ANS?
It has short preganglionic fibers.
Which of the following structures releases neurotransmitter molecules in a paravertebral ganglion?
Preganglionic sympathetic fiber
Which of the following structures is not associated with the autonomic nervous system?
All of these are associated with the autonomic nervous system.
Most preganglionic fibers in the sympathetic nervous system synapse with __________.
10-20 postganglionic neurons
The solar plexus is used as a name for the __________.
the celiac and mesenteric ganglia
The adrenal medulla secretes mostly ___________.
epinephrine (adrenaline)
The parasympathetic division arises from the __________ regions of the spinal cord.
brain and sacral
Damage to the __________ may affect near vision accommodation.
oculomotor nerve (CN III)
White rami carry _________ neurons, while gray rami carry _________ neurons.
myelinated preganglionic; unmyelinated postganglionic
Which of the following is not a characteristic of the enteric nervous system?
Its reflex arcs are associated with the spinal cord.
If a cell has α1 adrenergic receptors, it is sensitive to __________.
norepinephrine (NE)
Which of the following is not under dual control of the ANS?
Adrenal medulla activity
Propranolol, a beta-blocker, is typically used to __________.
decrease heart rate
Which of the following is more effective in producing bronchodilation?
Norepinephrine
Muscarinic receptors bind __________.
acetylcholine
The binding of __________ to a nicotinic receptor of a muscle fiber will __________ it.
acetylcholine; excite
Atropine is sometimes used to dilate the pupil for an eye examination. Which receptor would atropine block?
Muscarinic receptor
Antagonistic effects of the two divisions of the autonomic nervous system are exemplified in the control of __________.
gastrointestinal motility
__________ is an example of the cooperative effect between the two autonomic nervous system divisions.
Orgasm
Sympathetic fibers do not release __________.
nitric oxide (NO)
Sympathetic effects tend to last __________ than parasympathetic effects. One reason is that __________.
longer; norepinephrine can diffuse into the bloodstream without being broken down
The enzyme that breaks down norepinephrine (NE) is called __________.
monoamine oxidase (MAO)
A neuron that synapses in the adrenal medulla is a ___________ neuron, and releases the neurotransmitter ___________.
preganglionic; acetylcholine (ACh)
Drugs that are monoamine oxidase (MAO) inhibitors would most likely __________.
decrease the amount of NE destroyed and may be used as an antidepressant
A possible explanation for the effect of caffeine is that it blocks the receptor for a neuromodulator in the brain called __________, which inhibits ACh release by cholinergic neurons.
adenosine
Which one of the following is made up of primarily adrenergic fibers?
Postganglionic neurons of the sympathetic division
The __________ is an especially important center of autonomic control.
hypothalamus
Autonomic function receives input from all these except __________.
spinal cord
__________ nerve(s) pass(es) throughout sympathetic ganglia without synapsing.
Splanchnic
Which of the following is associated with the "flight-or-fight" reaction?
Reduced urinary output
The enteric nervous system controls the digestive system with no extrinsic control necessary.
false
Vasomotor tone is controlled by using the sympathetic division for vasodilation and the parasympathetic division for vasoconstriction.
false
Transduction begins with an action potential in a sensory receptor.
false
Sensory receptors sense only stimuli external to the body, such as light, sound waves, olfaction, and touch.
false
Most somesthetic signals in the right side of the body reach the cerebral cortex in the contralateral primary somesthetic area.
true
Fast pain is a localized response mediated by myelinated nerve fibers
true
Divergent sensory pathways explain the phenomenon of referred pain
false
Olfaction results from the stimulation of chemoreceptors.
true
Gustatory signals travel from the tongue through the facial and glossopharyngeal nerves.
true
The ossicles belong to the middle ear.
true
The macula sacculi is nearly horizontal and the macula utriculi is nearly vertical.
false
The vestibule contains organs of hearing and equilibrium.
false
The middle ear consists of a fluid-filled chamber.
false
The middle ear consists of a fluid-filled chamber.
true
Light falling on the retina is absorbed by rhodopsin and photopsin in the pigment epithelium.
false
Rods secrete glutamate from the base of the cell when exposed to light.
false
Vitamin A is necessary for the synthesis of rhodopsin.
true
The output energy of all receptors is a type of __________ energy.
electrical
The initial effect of a stimulus on a sensory receptor is a local electrical change specifically called a(an) __________.
receptor potential
What is a sensation?
A subjective awareness of a stimulus
Changes in cerebrospinal fluid pH are detected by __________.
chemoreceptors
Changes in blood pressure are detected by __________ in certain arteries.
mechanoreceptors
You can smell the fragrance of your deodorant when you just put it on, but after a little while the smell fades. What explains this phenomenon?
the phasic nature of olfaction
Which organ does not have nociceptors?
brain
Pain, heat, and cold are detected by __________.
free nerve endings
Which of the following is not an analgesic (pain reliever) found naturally in the central nervous system?
Bradykinin
Where do most second-order somesthetic neurons synapse with third-order neurons?
thalamus
Which of the following is not involved with spinal gating of pain signals?
lower motor neurons
In a taste bud, which cell produces a receptor potential?
Gustatory cells
Which of the following structures is visible to the naked eye?
Lingual papilla
Which taste sensation is produced by amino acids such as aspartic acid and glutamic acid?
Umami
What do pheromones stimulate?
olfactory cells
Where is the primary olfactory cortex located?
Temporal lobe
What is the only sense in which signals can reach the cerebral cortex without passing first through the thalamus?
Olfaction
The human ear can detect what frequency of vibrations?
20 to 20,000 Hz
Which of the following structures belong to the inner ear?
Semicircular duct
Which of the following structures houses the spiral organ?
Cochlea
The incus articulates with which bone(s)?
Malleus and stapes
Which structure acts as a transducer in the spiral organ?
Inner hair cell
The spiral organ is housed within which of the following structures?
Cochlear duct
Which structure allows upper respiratory infections to spread from the throat to the tympanic cavity?
Auditory (eustachian) tube
Stimuli produced by sound waves reach the brain following which pathway?
Auditory canal → tympanic membrane → ossicles → oval window → cochlear duct → spiral organ → fibers of cochlear nerve
Which of these is most vulnerable to irreversible damage caused by a very loud noise?
Cochlear hair cells
Each upward movement of the basilar membrane causes the stereocilia of the inner hair cells to bend, opening __________ gates.
K+
A 100 dB sound (loud) of 150 Hz (low pitch) would cause which of the following to occur?
The basilar membrane to vibrate vigorously near its distal end
When you spin while sitting in a swivel chair with your eyes closed, you can sense this movement by means of your __________.
semicircular ducts
When you travel in an elevator, what senses when the elevator is moving?
The hair cells of the otolithic membrane of the macula sacculi
The hair cells of the otolithic membrane of the macula sacculi
Dynamic equilibrium in angular acceleration
Which of the following does not contribute to the sense of equilibrium?
Vallate papillae
What is the correct order of cells in the retina from back to front?
Photoreceptor - bipolar - ganglion
Human vision is limited to wavelengths ranging from __________ nm.
400 to 700
Which of the following is not considered an accessory structure of the eye?
Cornea
Which of the following is not considered an optic component of the eye?
Retina
Glaucoma is a state of elevated pressure within the eye that occurs when the __________ is obstructed so the aqueous humor is not reabsorbed as fast as it is secreted.
scleral venous sinus
Nerve fibers from all regions of the retina converge on the __________ and exit the eye by way of the optic nerve.
optic disc
When you view objects close to the eye, the eye makes an adjustment called __________.
accommodation
An eye with which of the following conditions does not need a corrective lens to focus the image?
Emmetropia
Which cells are responsible for photopic (day) vision as well as trichromatic (color) vision?
cones
What event causes rhodopsin to go from violet to clear in color?
Cis-retinal straightens to become trans-retinal
Why do cones exhibit less neuronal convergence than rods?
Photopic vision has higher resolution than scotopic vision.
What are the only retinal cells that produce action potentials?
ganglion cells
Which of the following describes the duplicity theory of vision?
A single type of receptor system cannot produce both high sensitivity and high resolution.
What are the first-order neurons in the visual pathway?
bipolar cells
Half of the fibers of each optic nerve decussate at the __________.
optic chiasm
Adjustment to close-range vision involves all of the following except __________.
light adaptation
Which of the following are unencapsulated endings?
free nerve endings
Which of the following correctly describes the vestibular projection pathway to the brain?
Vestibular nerve - vestibulocochlear nerve - vestibular nuclei - thalamus - cerebral cortex
The three types of cones in the retina are differentiated from one another by what feature?
The absorption peak of their photopsin
Hormones are normally secreted via ducts into the bloodstream.
false
Hormones serve as intracellular messengers.
false
Testosterone is a gonadotropin
false
Many effects of growth hormone are mediated by insulin-like growth factors (IGFs) secreted by the pancreas.
false
Both the thymus and the pineal gland shrink after childhood.
true
Thyroid hormone has a calorigenic effect.
true
Epinephrine is said to have a glucose-sparing effect.
true
Cholesterol is essential for the synthesis of steroid hormones.
true
Peptide hormones are synthesized by cytoplasmic ribosomes as active enzymes.
false
Regardless of the cause of stress, the body reacts in a fairly consistent way to different stressors.
true
The exhaustion stage of the general adaptation syndrome (stress response) sets in only if protein reserves are depleted.
false
Eicosanoids are derived from steroids
false
Prostaglandins are considered paracrines.
true
Myxedema is characterized by low metabolic rate, sluggishness, and sleepiness
true
Addison disease is a consequence of a tumor of the adrenal medulla.
false
The nervous system reacts to stimuli __________ compared to the endocrine system, adapts __________ compared to the endocrine system, and has __________ effects compared to the endocrine system.
quickly; quickly; specific
Which of the following is true regarding endocrine glands?
They release their secretions into the blood.
_________ are secreted by one cell into the tissue fluid, diffuse to nearby cells in the same tissue, and stimulate their physiology.
Paracrines
The ___________ can be found as part of the epithalamus, near the superior colliculi of the midbrain.
pineal gland
The _________ secretes growth hormone, which is also known as somatotropin.
anterior pituitary
The __________ is not an endocrine gland but it has a role in endocrine function.
kidney
Which of the following is the correct abbreviation for the hormone that stimulates the anterior pituitary to secrete ACTH?
CRH
What makes a cell responsive to a particular hormone?
The presence of a receptor for that particular hormone
The posterior pituitary secretes _________.
oxytocin (OT)
The anterior pituitary is __________ than the posterior pituitary and has __________ connection to the hypothalamus.
larger; no nervous
Thyrotropin-releasing hormone targets the __________.
anterior pituitary
The hypophyseal portal system connects the _________ with the _________.
anterior pituitary; hypothalamus
Which of the following is not a hypothalamic hormone?
Luteinizing hormone (LH)
Antidiuretic hormone (ADH) targets the __________.
kidneys
Of the following hormones, which has more target cells in the body than the others?
Growth hormone (GH)
Target organs most often regulate the pituitary gland via _________.
negative feedback inhibition
The infundibulum is a ___________.
projection of the hypothalamus from which the pituitary gland hangs
__________ secretion is controlled by neuroendocrine reflexes, whereas __________ secretion is controlled by negative feedback mechanisms.
Oxytocin (OT); antidiuretic hormone (ADH)
Negative feedback inhibition occurs when __________.
thyroid hormone (TH) targets the anterior pituitary
Which hormone stimulates glucocorticoid secretion?
ACTH
Which of these hormones does not stimulate the release of another hormone by its target cells?
PRL
The hormone called _________ plays an important role in synchronizing physiological function with the cycle of daylight and darkness.
melatonin
The __________ secretes several hormones that stimulate the development of lymphatic organs and regulates development and activity of T cells (white blood cells).
thymus
The __________ secretes a hormone that increases the body's metabolic rate, promotes alertness, quickens reflexes, and stimulates the fetal nervous system.
thyroid gland
The __________ secrete(s) a hormone as a response to hypocalcemia.
parathyroid glands
The __________ secrete(s) __________, which promotes Na+ and water retention.
adrenal cortex; aldosterone
The zona fasciculata in the adrenal gland secretes ___________.
cortisol
The zona fasciculata in the adrenal gland secretes ___________.
glucagon; raises
Which of the following is not secreted by the pancreas?
Somatotropin (growth hormone)
Which of the following organs has both endocrine and exocrine functions?
the ovary
Which of the following is not a steroid hormone?
insulin
Which of the following is synthesized in the rough endoplasmic reticulum?
glucagon
The absence of iodine in the diet leads to __________.
hypothyroidism
T4 and T3 are __________ hormones that are mainly transported __________ in the blood.
monoamine; bound to thyroxine-binding globulin (TBG)
Which of the following enters a target cell's nucleus and acts directly on the genes.
Estrogen
Which of the following is the last step in the sequence of events happening when cyclic AMP acts as a second messenger?
Enzymes are activated or deactivated by the action of protein kinases
Which of the following makes it possible for even a small quantity of hormone to have a strong effect on its target cell?
Enzyme amplification
Which of the following is an increase in the number of receptors making a target cell more sensitive to a hormone?
Up-regulation
Circulating hormones are mostly taken up and degraded by the _________ and the __________.
liver; kidneys
Neither follicle stimulating (FSH) hormone nor testosterone alone can stimulate significant sperm production, whereas when they act together, the testes produce some 300,000 sperm per minute. This is an example of which principle regarding hormones?
The synergistic effect
Glucagon increases blood glucose concentration and insulin decreases it. This is an example of _____.
the antagonistic effect
The resistance stage in the general adaptation syndrome (stress response) is dominated by __________.
cortisol
Any situation that upsets homeostasis and threatens one’s physical or emotional well-being is called __________.
stress
During the exhaustion stage of the general adaptation syndrome (stress response), stress overwhelms homeostasis. One characteristic of this stage is that __________.
energy demands are met primarily by protein metabolism
Which of the following is true regarding cortisol?
It promotes breakdown of fat and protein.
The initial response to stress is called the _________ and is mediated mainly by __________.
alarm reaction; norepinephrine and epinephrine
Eicosanoids are derived from __________.
arachidonic acid
Which of the following is not a role of prostaglandins?
To stop fever and pain
Aspirin and ibuprofen block the __________.
action of cyclooxygenase
Diabetes insipidus is caused by __________.
antidiuretic hormone (ADH) hyposecretion
Which of the following effects on a gland can be caused by a tumor?
Hyposecretion and hypersecretion
Which of the following is not a cause of Cushing syndrome?
Hyperactivity of the adrenal medulla
Growth hormone (GH) hypersecretion causes gigantism when it begins in childhood, but it is more likely to cause __________ when it begins in adulthood.
acromegaly
Which of the following is not a characteristic of diabetes mellitus?
Hypoglycemia
Which of the following statements about diabetes mellitus is false?
Both type I and type II DM are characterized by lack of, or low levels of, insulin.
Which of the following is the correct sequence of events leading to the polyuria and dehydration associated with diabetes mellitus?
Hyperglycemia → glucose enters renal tubules → glucose transport maximum exceeded → glucose in urine raises osmolarity of tubular fluid → osmotic diuresis
TEST and EST are abbreviations for testosterone and estrogen.
false
Hormones that bind to proteins while transported in the blood generally have a longer half-life.
true
Worrying about your upcoming exam in history class is a valid form of stress
true