The Special Senses and Endocrine System

Question 1

Nutrients are delivered and waste products are carried away from the cells of the posterior segment of the eye by blood vessels. However, the cells in the cornea and lens (in the anterior segment) are avascular. Which is the best explanation for how these cells are maintained?
Select one:
a. These cells, like the cells of the corneal layer of the integument are not living cells.
b. The nutrients and waste products of the anterior segment diffuse into and through the vitreous humor of the posterior segment.
c. The aqueous humor is continuously replenished and flows from the ciliary process to drain in the scleral venous sinus
d. The metabolic activity of these cells is very low. They produce little waste and need few nutrients.

Answer 1

c. The aqueous humor is continuously replenished and flows from the ciliary process to drain in the scleral venous sinus

Question 2

In a person who is color-blind, which of the following would you most expect to see?
Select one:
a. a loss of functions in the rods of their retina
b. a loss of their peripheral vision
c. absence of green or red cones in their fovea
d. an inability to regenerate 11-cis-retinal after bleaching

Answer 2

c. absence of green or red cones in their fovea

Question 3

Which of the following is the best explanation of why it is difficult to discriminate the color of an object at night?
Select one:
a. At night, dilation of pupils stimulates the retina, where more rods are located rather than cones.
b. Cones come in three types, each sensitive to different wavelengths of light.
c. The foveae are densely packed with cones.
d. As many as 100 cones may converge on one ganglion cell.

Answer 3

a. At night, dilation of pupils stimulates the retina, where more rods are located rather than cones.

Question 4

Which of the following best describes the function of the iris?

Select one:

a. controls amount of light entering eye
b. gives the eye its color
c. refracts light through the pupil
d. adjusts the shape of the lens

Answer 4

a. controls amount of light entering eye

Question 5

The elasticity of the lens decreases with age. This leads to which of the following?
Select one:
a. a clouding of the lenses known as a cataract
b. less accommodation of the lenses and difficulty focusing on nearby objects
c. less light getting to the retina and diminished visual acuity
d. lowered accommodation of the pupillary reflex and blurry vision

Answer 5

b. less accommodation of the lenses and difficulty focusing on nearby objects

Question 6

If you shine a light into one eye both pupils will constrict. The best explanation for this is ________.

Select one:

a. sensory input from the retinas of both eyes converges at the optic chiasm and information from each eye is delivered to both the left and right sides of the brain
b. a small portion of light always enters the other eye
c. information from one eye is directly and immediately transferred to the other eye to maintain alignment of the eyes
d. This, in fact, does not occur; information from both eyes is always separated.

Answer 6

a. sensory input from the retinas of both eyes converges at the optic chiasm and information from each eye is

Question 7

Humans can smell as many as 10,000 different odors but have significantly fewer types of olfactory receptors. Which of the following is the best explanation for why humans can distinguish so many smells?

Select one:

a. Taste receptors that are active at the same time influence the subtlety of what we smell.
b. The olfactory pathway travels to location in the brain in which memories are formed and we simply mix this new sensory information with old memories.
c. The sensation of a single, distinct smell is a combination of a variety of chemicals that stimulate different combinations of olfactory receptor cells all at once.
d. The belief that we can smell so many different distinct odors is a psychological process referred to as an uncinate fit or olfactory hallucination.

Answer 7

c. The sensation of a single, distinct smell is a combination of a variety of chemicals that stimulate different combinations of olfactory receptor cells all at once.

Question 8

Labyrinthitis is a medical condition often caused by a viral infection, resulting in swelling and inflammation of the membranous labyrinth. Which of the following symptoms would you most associate with the condition of labyrinthitis?

Select one:

a. auditory hallucination
b. loss of balance and dizziness
c. loss of hearing
d. ringing in the ears (tinnitus)

Answer 8

b. loss of balance and dizziness

Question 9

The sensation of loudness or the volume of a sound is detected by ________.

Select one:

a. greater movement of the basilar membrane resulting in greater deflection of the hair cells
b. vibration along a greater length of the basilar membrane, stimulating a greater number of hair cells
c. faster vibration of the basilar membrane resulting in a higher frequency of hair cell stimulation
d. sounds that can travel all the way to the apex of the scala vestibule with enough energy remaining to deflect hair cells

Answer 9

a. greater movement of the basilar membrane resulting in greater deflection of the hair cells

Question 10

A patient has a loss of hearing in only one ear. Which of the following is likely to be a result?
Select one:
a. The patient will have a loss of balance with dizziness and vertigo.
b. The patient will have increased sensitivity to sound in the unaffected ear.
c. The patient will not be able to track objects with the eye on the same side as the hearing loss
d. The patient will not be able to localize the origin of sounds.

Answer 10

d. The patient will not be able to localize the origin of sounds.

Question 11

Dancers will use a technique called “spotting” when they perform spins of the body. By holding their head and eyes on a fixed point in front of them as their body spins they reduce the amount of head spinning and this prevents dizziness. Which of the following is the most likely explanation for why this works?

Select one:

a. When the eyes send a static vision of stability to the brain, it is tricked into believing the body is still and therefore dizziness will not occur.
b. This helps keep the motions detected by the eyes congruent (aligned) with the motions sensed by the vestibular apparatus.
c. This will help to reduce the lateral flection of the head and will prevent hyper polarization or depolarization of the hair cells in the macula.
d. Reducing the inertia of head spin will reduce the flow of endolymph that deflects the hair cells of the crista ampullaris.

Answer 11

d. Reducing the inertia of head spin will reduce the flow of endolymph that deflects the hair cells of the crista ampullaris.

Question 12

Tom is a 45-year-old male that has lost his ability to hear high frequency sounds. The most likely explanation for this would be ________.

Select one:

a. a perforated tympanic membrane
b. a middle ear infection
c. damage to the hair cells near the oval window in the cochlear duct
d. an overgrowth of bony tissue, fusing the ossicles together

Answer 12

c. damage to the hair cells near the oval window in the cochlear duct

Question 13

What is the main function of the rods in the eye?

Select one:

a. depth perception
b. color vision
c. vision in dim light
d. accommodation for near vision

Answer 13

c. vision in dim light

Question 14

Receptors for hearing are located in the \_\_\_\_\_\_\_\_.
Select one:
a. cochlea 
b. semicircular canals
c. tympanic membrane
d. vestibule

Answer 14

a. cochlea

Question 15

Which of the following types of neurons are replaced throughout adult life?

Select one:

a. olfactory receptor cells
b. retinal bipolar cells
c. retinal ganglion cells
d. auditory outer and inner hair cells

Answer 15

a. olfactory receptor cells

Question 16

Bitter taste is elicited by ________.

Select one:

a. hydrogen ions
b. alkaloids
c. acids
d. metal ions

Answer 16

b. alkaloids

Question 17

The ability to clearly see objects at a distance but not close up is properly called \_\_\_\_\_\_\_\_.
Select one:
a. myopia
b. hypopia
c. hyperopia 
d. presbyopia

Answer 17

c. hyperopia

Question 18

Seventy percent of all sensory receptors are located in the ________.

Select one:

a. eye
b. ears
c. skin
d. nose

Answer 18

a. eye

Question 19

As sound levels increase in the spiral organ (of Corti), ________.

Select one:

a. outer hair cells stiffen the basilar membrane
b. outer hair cells bend the cilia away from the kinocilium
c. inner hair cells stiffen the basilar membrane
d. inner hair cells bend the cilia away from the kinocilium

Answer 19

a. outer hair cells stiffen the basilar membrane

Question 20

Which of the following is true about gustatory receptors?

Select one:

a. In order for a chemical to be sensed, it must be hydrophobic.
b. The receptors generate an action potential in response to chemical stimuli.
c. Complete adaptation occurs in about one to five minutes.
d. All gustatory receptors have the same threshold for activation.

Answer 20

c. Complete adaptation occurs in about one to five minutes.

Question 21

Which of the following taste sensations is incorrectly matched to the chemicals that produce it?

Select one:

a. sweet-organic substances such as sugar and some lead salts
b. sour-acids
c. salty-metal ions
d. bitter-alkaloids
e. umami-triglycerides and fatty acids

Answer 21

e. umami-triglycerides and fatty acids

Question 22

Which of the following types of receptors are located in the mouth?

Select one:

a. chemoreceptors, mechanoreceptors, thermoreceptors, and nociceptors
b. chemoreceptors only
c. chemoreceptors, thermoreceptors, and nociceptors only
d. thermoreceptors, mechanoreceptors, and nociceptors only

Answer 22

a. chemoreceptors, mechanoreceptors, thermoreceptors, and nociceptors

Question 23

Motion sickness seems to ________.

Select one:

a. respond best to medication taken after salivation and pallor begins
b. respond best to medication that “boosts” vestibular inputs
c. result from activation of nausea centers in the brain stem
d. result from mismatch between visual and vestibular inputs

Answer 23

d. result from mismatch between visual and vestibular inputs

Question 24

Which pairing of terms is incorrectly related?

Select one:

a. frequency of sound waves: loudness of the sound
b. quality of a sound: frequency of the sound
c. amplitude of a sound: intensity of the sound
d. frequency of sound waves: number of wavelengths

Answer 24

a. frequency of sound waves: loudness of the sound

Question 25

A patient who has experienced previous jaw and face trauma now reports difficulty tasting with the tip of her tongue. Which cranial nerve was likely damaged in that injury?

Select one:

a. Glossopharyngeal (IX)
b. Facial (VII)
c. Hypoglossal (XII)
d. Trigeminal (V)

Answer 25

b. Facial (VII)

Question 26

Gluconeogenesis, the formation of glucose from fats and proteins, is due to the action of ________.

Select one:

a. aldosterone
b. insulin
c. secretin
d. cortisol

Answer 26

d. cortisol

Question 27

Normal development of the immune response is due in part to hormones produced by the ________.

Select one:

a. adrenal medulla
b. pancreas
c. thyroid gland
d. thymus gland

Answer 27

d. thymus gland

Question 28

Virtually all amino acid-based hormones exert their signaling effects through intracellular ________.

Select one:

a. calcium
b. deactivating ions
c. nucleotides
d. second messengers

Answer 28

d. second messengers

Question 29

Chemical substances secreted by cells into the extracellular fluids that travel through the blood and regulate the metabolic function of other cells in the body are called ________.

Select one:

a. enzymes
b. antibodies
c. proteins
d. hormones

Answer 29

d. hormones

Question 30

Which of the following can act on receptors inside the target cell that directly activate specific genes?

Select one:

a. growth hormone
b. testosterone
c. calcitonin
d. melatonin

Answer 30

b. testosterone

Question 31

Oxytocin ________.

Select one:

a. release is an example of a positive feedback control mechanism
b. is an anterior pituitary secretion
c. exerts its most important effects during menstruation
d. controls milk production

Answer 31

a. release is an example of a positive feedback control mechanism

Question 32

Antidiuretic hormone (ADH) ________.

Select one:

a. increases urine production
b. promotes dehydration
c. is produced by the anterior pituitary
d. secretion is inhibited by alcohol

Answer 32

d. secretion is inhibited by alcohol

Question 33

Which of the following hormones suppresses appetite and increases energy expenditure?

Select one:

a. gastrin
b. secretin
c. leptin
d. aldosterone

Answer 33

c. leptin

Question 34

The ability of a specific tissue or organ to respond to the presence of a hormone is dependent on ________.

Select one:

a. the location of the tissue or organ with respect to the circulatory path
b. the membrane potential of the cells of the target organ
c. the presence of the appropriate receptors on the cells of the target tissue or organ
d. nothing—all hormones of the human body are able to stimulate any and all cell types because hormones are powerful and nonspecific

Answer 34

c. the presence of the appropriate receptors on the cells of the target tissue or organ

Question 35

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 ________.

Select one:

a. hepatic portal system
b. general circulatory system
c. hypophyseal portal system
d. feedback loop

Answer 35

c. hypophyseal portal system

Question 36

Steroid hormones exert their action by ________.

Select one:

a. entering the nucleus of a cell and initiating or altering the expression of a gene
b. binding cell receptors and initiating cAMP activity
c. entering the cell and activating mitochondrial DNA
d. activating the hypothalamic release of regulating hormones

Answer 36

a. entering the nucleus of a cell and initiating or altering the expression of a gene

Question 37

Hormones often cause a cell to elicit multiple responses; this is because ________.

Select one:

a. there are thousands of receptors on the cell membrane
b. the receptors bind to several hormones at the same time
c. the protein kinases are rapidly metabolized into functional amino acids
d. during protein kinase activation, enzymes phosphorylate many other enzymes

Answer 37

d. during protein kinase activation, enzymes phosphorylate many other enzymes

Question 38

Which of the following statements is true of amino acid-based hormones?

Select one:

a. They cross the plasma membrane.
b. They are lipid soluble.
c. They are synthesized from cholesterol.
d. They require a receptor in the plasma membrane.

Answer 38

d. They require a receptor in the plasma membrane.

Question 39

Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________.

Select one:

a. insulin, because insulin is a small peptide
b. steroid hormones, because both diffuse easily into target cells
c. growth hormone, because the thyroid works synergistically with thyroid hormone
d. glucagon, because the structure of glucagon is similar to that of thyroid hormone

Answer 39

b. steroid hormones, because both diffuse easily into target cells

Question 40

The major targets of growth hormone are ________.

Select one:

a. the blood vessels
b. the thyroid and adrenal glands
c. the liver and gall bladder
d. liver, bones, and skeletal muscles

Answer 40

d. liver, bones, and skeletal muscles

Question 41

Mineralocorticoid is to aldosterone as glucocorticoid is to ________.

Select one:

a. testosterone
b. estrogen
c. cortisol
d. epinephrine

Answer 41

c. cortisol

Question 42

Leptin is secreted by ________.

Select one:

a. lymphocytes
b. adipose cells
c. goblet cells
d. fibroblasts

Answer 42

b. adipose cells

Question 43

The single most important regulator of calcium levels in the blood is ________.

Select one:

a. calcitonin
b. parathyroid hormone
c. thyroid hormone
d. gonadotropic hormones

Answer 43

b. parathyroid hormone

Question 44

Hormones that bind to plasma proteins ________.

Select one:

a. are usually water soluble
b. must also bind to plasma membrane receptors
c. are usually made of amino acids
d. are usually synthesized from cholesterol

Answer 44

d. are usually synthesized from cholesterol

Question 45

Regulating hormones from the hypothalamus ________.

Select one:

a. enter venous circulation and travel to the heart, which pumps the hormone-containing blood to the pituitary
b. enter the hepatic portal system, which feeds the pituitary
c. travel by arteries to the pituitary
d. first enter into the hypophyseal portal system

Answer 45

d. first enter into the hypophyseal portal system

Question 46

The effect of a hormone on a target cell may be decreased by the presence of ________.

Select one:

a. antagonistic hormones
b. permissive hormones
c. synergistic hormones
d. plasma membrane receptors

Answer 46

a. antagonistic hormones

Question 47

Aldosterone ________.
Select one:
a. is secreted by the posterior pituitary
b. functions to increase sodium reabsorption
c. presence increases potassium concentration in the blood
d. production is greatly influenced by ACTH

Answer 47

b. functions to increase sodium reabsorption

Question 48

A release of parathyroid hormone (PTH) will trigger ________.

Select one:

a. increased osteoblast activity
b. a reduction of calcium reabsorption in the kidney tubules
c. increased activation of vitamin D by the kidney
d. a drop in blood calcium levels

Answer 48

c. increased activation of vitamin D by the kidney

Question 49

How do glucocorticoids enable the body to deal appropriately with stress?

Select one:

a. by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
b. by decreasing the heart rate, thus decreasing blood pressure
c. by stimulating the pancreas to release insulin
d. by releasing the neurotransmitters that prepare the body for the stress response

Answer 49

a. by increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure

Question 50

Which hormone has only one known effect: to stimulate milk production by the breasts?

Select one:

a. progesterone
b. estrogen
c. oxytocin
d. prolactin

Answer 50

d. prolactin