BIO 202 15&16

Visual processing in the thalamus does NOT contribute significantly to ________.

night vision

Most newborns ________.

often use only one eye at a time

Most taste buds are located __________.

on the top surface of the fungiform papillae

What structure in the eye creates a visual blind spot?

optic disc

Enterochromaffin-like cells of the gastric mucosa can be triggered to release histamine. Histamine, in this case, causes nearby parietal cells of the stomach lining to produce hydrochloric acid. The effect of histamine on parietal cells would best be described as a(n) ________.

paracrine

Which gland secretes the most important hormone controlling calcium balance in the blood?

parathyroid

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

parathyroid hormone

In the visual pathways to the brain, the optic radiations project to the ________.

primary visual cortex

Which hormone stimulates mammary glands to produce milk in nursing mothers?

prolactin

Which of the following triggers the release of glucagon?

prolonged fasting

Which of the following is NOT believed to be causally linked to the development of type 2 diabetes (non-insulin dependent diabetes mellitus)?

regular cardiovascular exercise

Oxytocin ________.

release is an example of a positive feedback control mechanism

Motion sickness seems to ________.

result from mismatch between visual and vestibular inputs

Which photoreceptor cells respond to very dim light?

rods

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

second messengers

Antidiuretic hormone (ADH) ________.

secretion is inhibited by alcohol

Pheochromocytoma produces symptoms of uncontrolled sympathetic nervous system activity. Which of the following is common to both adrenal chromaffin cells and adrenergic fibers of the sympathetic nervous system?

secretion of norepinephrine

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

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

Which of the following is NOT a component of the cyclic AMP signaling mechanism?

steroid

Which part of the visual pathway is responsible for our daily biorhythms?

suprachiasmatic nucleus

Which of the following occurs in situations where different hormones produce the same effects at the same target cell and their combined effects are amplified?

synergism

The malleus, incus, and stapes of the middle ear are joined by tiny _____.

synovial joints

Which accessory eye structure is not correctly matched with one of its functions?

tarsal glands: produce tears

Which structure contains the blood vessels that nourish all layers of the eye?

the choroid

Which portion of the ear is responsible for sound transduction?

the cochlea

Congenital sensorineural deafness most commonly involves damage to ______.

the cochlear hair cells

What determines whether a particular cell is able to respond to a hormone?

the presence of a specific hormone receptor

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

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

Which of the following nerves would you predict is NEVER involved in the development of strabismus?

trigeminal (V)

The various hormones secreted by the anterior pituitary that regulate the secretion of hormones from other endocrine organs are called __________.

tropins

Atrial natriuretic peptide is a hormone that controls blood pressure in part by increasing the urinary excretion of sodium.

true

Both "turn on" factors (hormonal, humoral, and neural stimuli) and "turn off" factors (feedback inhibition and others) may be modulated by the activity of the nervous system.

true

Cyclic AMP (cAMP), diacylglycerol (DAG), inositol triphosphate (IP3), and calcium ions can serve as second messengers.

true

The adrenal medulla is stimulated to release catecholamines during a stress response.

true

The beta cells in the pancreatic islets produce insulin.

true

The number of receptors for a particular hormone can change due to consistently high or low levels of that hormone, which is referred to as up- and down-regulation.

true

Type 2 diabetes mellitus may reflect declining receptor sensitivity to insulin rather than decreased insulin production.

true

Which of the following is the basic taste quality responsible for the amino acid flavor of steak?

umami

In circumstances where the body requires prolonged or increased levels of a hormone, the DNA of target cells will specify the synthesis of more receptors on the surface of the cells of the target organ. This is known as ________.

up-regulation

The only special sense NOT fully functional at birth is the sense of ________.

vision

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

vision in dim light

Which of the following pairs correctly matches the adrenal gland structure with the class of hormones it produces?

zona glomerulosa: mineralocorticoids

Your patient has been diagnosed with Type I diabetes mellitus, and you are explaining how to administer insulin. Your patient states, "I don't want to do this. My brother-in-law has diabetes, and he just takes a pill and watches what he eats." What is your best response?

"Your relative may have Type II diabetes. People with that condition can make insulin, but their cells don't respond to it properly. Your pancreas doesn't manufacture insulin."

Which of these conditions would promote aldosterone release from the adrenal glands?

A drop in blood pressure is sensed in the kidney.

You realize that many of your geriatric patients have visual problems that impact their care. Which item is NOT a common cause of decreased visual acuity in the elderly?

Abnormal production of vitreous humor

Hypocalcemia could be caused by the ______.

All of the listed responses are correct (apoptosis of parathyroid cells, failure of osteoclasts to respond to PTH (parathyroid hormone/parathormone), malfunction of the parathormone receptors in kidney tubule cells)

Which of the following hormone pairs exhibit an antagonistic relationship?

Angiotensin II & ANP

Humans can see several thousand shades of color but have cone photoreceptors that are sensitive to only three (perhaps four) wavelengths of light. What is the best explanation for why we see so many colors?

Color perception is achieved by activation of various combinations between the three cone types.

Adult onset diabetes, diabetes type 2, can best be described using which of the following concepts?

Constantly high blood sugar leads to high insulin release. High amounts of insulin lead to down-regulation of insulin receptors.

A patient has noticed that his ability to hear has recently decreased. Which item is NOT likely to have caused his problem?

Damage to the semicircular canals

You may predict that iodized salt may be effective in preventing all EXCEPT which of the following?

Graves' disease

Damage of which of the following brain structures could cause central diabetes insipidus?

Hypothalamus

A patient is being treated by her urologist for a fourth episode of kidney stones. Analysis of the stones shows that they are composed of calcium oxalate. The urologist orders an assay of which hormone?

Parathyroid hormone (PTH)

Your patient has been admitted to the intensive care unit with a severe head injury. As you monitor his urine output, you find that it has fallen sharply. Lab tests indicate that his serum osmolality is lower than normal (i.e., his plasma is too dilute). What should you suspect?

Syndrome of inappropriate antidiuretic hormone (SIADH)

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?

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

Which of the following is a characteristic of the lens?

The lens focuses light on the retina

Which of the following is true of receptors for dynamic equilibrium?

The receptors for dynamic equilibrium respond to rotational forces.

Which cellular organelle is the site of synthesis of amino acid-based hormones? Which cellular organelle is the site of synthesis of steroid hormones?

The ribosome; smooth endoplasmic reticulum

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?

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.

Richard Neis had symptoms of excessive secretion of PTH (high blood calcium levels), and his physicians were certain he had a parathyroid gland tumor. Yet when surgery was performed on his neck, the surgeon could not find the parathyroid glands at all. Where should the surgeon look next to find the tumorous parathyroid gland?

The surgeon should check Richard's thoracic cavity

Which of the following is NOT a characteristic of olfactory receptor cells?

They are unipolar neurons.

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

They require a receptor in the plasma membrane.

Which of the following is NOT representative of endocrine glands?

They use ducts to secrete their products into the surrounding tissue fluid.

Which of the following would result from hypoparathyroidism?

a decrease in the release of calcium from bones

In a person who is color-blind, which of the following would you most expect to see?

absence of green or red cones in their foveae

What is the primary function of hormones?

act as chemical messengers that regulate the metabolic function of cells in the body

Which of the following is NOT an endocrine gland?

adenoid

What hormone released into the blood by the posterior pituitary would reduce the amount of urine that is formed?

antidiuretic hormone (ADH)

Hormones that bind to plasma proteins ________.

are usually synthesized from cholesterol

Which of the following is LEAST likely to explain why a person has anosmia?

being young

Which of the cell types would secrete their product if the blood glucose level was rising, as during digestion of a meal?

beta cells

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

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

What ion is sometimes used as a second messenger of amino acid-based hormones?

calcium

What is the target of thyroid hormones?

cells of the body

Hormones bring about their characteristic effects by altering target cell activity, increasing or decreasing the rates of normal cellular processes. Which of the following is NOT a typical effect brought on by hormones?

changing the structure of the target cell's cytoskeleton

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

chemoreceptors, mechanoreceptors, thermoreceptors, and nociceptors

Which structure is NOT matched with its function?

ciliary body: focus the pupil

Aqueous humor forms during capillary filtration in the __________?

ciliary processes (part of the ciliary body).

If retinal detachment occurs in the macula lutea, one can predict that there would be a significant loss of ______.

color vision

During close vision, what actions must the eye take to bring an object into focus?

contract the ciliary body

What term refers to the eyes moving medially to track items close at hand?

convergence

As light travels through the eye, it passes through several structures or chambers before reaching the retina. Which list below gives those structures in the correct order?

cornea, anterior chamber, pupil, lens, posterior segment

Nerve fibers from the medial aspect of each eye ________.

cross over to the opposite side at the chiasma

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 ________.

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

Aldosteronism will cause ______.

decreased secretion of renin

Which of the following is NOT a change that may be caused by hormonal stimulus?

direct control of the nervous system

Hormones often cause multiple responses in a cell. This is because ______.

during protein kinase activation, enzymes phosphorylate many other enzymes

Glands that secrete their products into surrounding tissue fluids are classified as ______ glands, whereas glands that secrete onto a membrane surface are classified as _____ glands.

endocrine; exocrine

Which of the following is not a major type of stimulus that triggers endocrine glands to manufacture and release hormones?

enzymatic

Which of the following is NOT a steroid-based hormone?

epinephrine

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

eye

As light hits the retina, the first structure the light encounters is a rod or a cone.

false

Direct gene activation involves a second-messenger system.

false

Oxytocin and ADH are produced in the posterior pituitary.

false

The hypothalamus is known to control the activity of the thyroid, which has traditionally been called the master endocrine gland.

false

Up-regulation involves the loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.

false

Water-soluble hormones are inactivated and removed from the blood by the liver.

false

Taste buds are NOT found ________.

filiform papillae

Regulating hormones from the hypothalamus ________.

first enter into the hypophyseal portal system

Which of the following hormones has significantly different effects when it is released in males instead of females?

follicle-stimulating hormone

Name the types of papillae that contain taste buds.

fungiform, foliate, and vallate

The cells of the retina in which action potentials are generated are the ________.

ganglion cells

There are three layers of neurons in the retina. The axons of which of these neuron layers form the optic nerves?

ganglion cells

In glaucoma, damage occurs primarily to the ______.

ganglion cells in the retina

The receptor membranes of gustatory cells are ________.

gustatory hairs

Ordinarily, it is NOT possible to transplant tissues from one person to another, yet corneas can be transplanted without tissue rejection. This is because the cornea ________.

has no blood supply

What stimuli does the vestibular apparatus detect?

head position in space

What is directly required for the production of anterior pituitary gland hormones?

hormonal stimuli

Low blood glucose concentration and high blood potassium concentration are examples of __________ stimuli for an endocrine gland.

humoral

What type of stimulation controls parathyroid release?

humoral

One of the least complicated of the endocrine control systems directly responds to changing blood levels of ions and nutrients. Which of the following describes this mechanism?

humoral stimulation

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 ________.

hypophyseal portal system

Acromegaly may be caused by all EXCEPT which of the following?

hyposecretion of GH in adulthood

Hyperprolactinemia may be caused by ______.

hyposecretion of dopamine

Where is thyrotropin-releasing hormone (TRH) made?

hypothalamus

Where are equilibrium receptors located?

in the semicircular canals and in the vestibule of the ear

Adrenocortical androgens are normally converted in females into estrogens. However, in adrenogenital syndrome, females develop a beard and a masculine pattern of body hair distribution; this occurs due to ______.

insufficient level of enzymes that convert androgens into estrogens

A blow to the head may cause diabetes insipidus by ______.

interfering with the normal transmission of nerve impulses to the posterior pituitary

During otitis media, large amounts of fluid or pus may accumulate in the tympanic cavity; the fluid is primarily ______.

interstitial fluid

What structure regulates the amount of light passing to the visual receptors of the eye?

iris

Melatonin ________.

is responsible for regulating the sleep cycle

The posterior lobe of the pituitary gland is NOT a true endocrine gland because ________.

it is only a hormone storage area that receives hormones from the hypothalamus for release

Thyroxine is a peptide hormone, but its mechanism is different from other peptide hormones. Which of the following statements is true concerning this difference?

It does not require a second messenger to cause a response

People who lose their sense of taste may also lose interest in eating. Which of the following is involved in the perception of tastes?

Much of what is perceived as a taste defect may actually be a defect in olfaction, which causes foods and beverages to taste differently.

Which of the following is a hormone produced by the posterior pituitary?

None of the listed responses is correct.

How are the olfactory receptors activated?

Odorants dissolve in the mucus and bind to receptors.

Overlap in the visual fields of our eyes ________.

allows us to subconsciously estimate the distance of objects based on the different angles the image strikes our two retinas

The blind spot of the eye is caused by ________.

an absence of photoreceptors where the optic nerve leaves the eye

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

antagonistic hormones

What gland secretes growth hormone?

anterior pituitary

Which hormone aids in water resorption?

antidiuretic hormone

The elasticity of the lens decreases with age. This leads to which of the following?

less accommodation of the lenses and difficulty focusing on nearby objects

What property of a hormone would allow it to pass unassisted through a plasma membrane?

lipid-soluble

Damage to the medial portion of the optic chiasm, cause by a pituitary tumor, would lead to __________.

loss of peripheral vision

What are the names of the bones in the inner ear, in order from left to right?

malleus, incus, stapes

Upon landing at the airport in Lagos, Nigeria, Eric feels wide awake even though the local time is 11pm. Which synthetic hormone supplement could he administer to help adjust to the new time zone?

melatonin