Chapter 16

After brain surgery, a patient receiving postoperative care in an intensive care unit began to pass large volumes of very dilute urine. The ICU nurse administered a medicine that mimics which of the following hormones?

ADH

Why are Tanya's cells starved for sugar (glucose) if there is so much glucose in the blood?

Tanya's cells don't recognize the messages telling them to let the glucose inside

What is the primary role of G protein in the cell?

The G protein acts as a middleman between the extracellular first messenger and the intracellular second messenger.

How do endocrine hormones reach their target cells?

The blood stream allows hormones to be distributed throughout the body.

Why is the plasma membrane a barrier for thyroid hormone to enter a cell, but steroid hormones pass through easily?

The cell membrane is a barrier to certain molecules but not to others. The cell membrane is more permeable to small, uncharged, nonpolar molecules.

Which of the following enzymes are important in the deactivation of cAMP and termination of signaling?

The increase in cAMP levels is usually short-lived because the enzyme phosphodiesterase is constantly present in the cytoplasm of the target cells.

Which type of hormone is associated with an increase in ATP production?

The mitochondria increase their production of ATP as a result of thyroid hormone binding to receptors on their surface.

Describe the locations of the parathyroid glands. (Module 16.9A)

They are embedded in the posterior surfaces of the lateral lobes of the thyroid gland. Submit

What hormone also aids the stress response by promoting water retention and acting as a vasoconstrictor?

Yes, ADH increases water reabsorption in the distal tubule and collecting duct of the nephron and its secondary function is to act as a vasoconstrictor.

The hormone that dominates during the alarm phase of the general adaptation syndrome (GAS) is

epinephrine

The adrenal medulla produces the hormones

epinephrine and norepinephrine.

During which phase of the general adaptation syndrome is there a collapse of vital systems? (Module 16.17C)

exhaustion phase

Alpha cells are to ________ as beta cells are to ________.

glucagon; insulin Submit

Norepinephrine and epinephrine are considered to be ________ when released into the bloodstream, but ________ when released at synapses.

hormones; neurotransmitters

Cushing's disease is a result of which of the following?

hypersecretion of glucocorticoids Submit

Which endocrine structure synthesizes hormones involved with fluid balance and smooth muscle contraction?

hypothalamus

The parathyroid glands produce a hormone that

increases the level of calcium ions in the blood.

Which anterior pituitary hormone induces ovulation in females and stimulates sex hormone production by the interstitial cells of the testes in males?

luteinizing hormone (LH) Submit

The inner portion of the adrenal gland is the

medulla.

The zona glomerulosa of the adrenal cortex produces

mineralocorticoids.

When one hormone is needed for a second hormone to produce an effect, it is called

permissive.

Cyclic AMP is degraded by __________.

phosphodiesterase

Melatonin is produced by the

pineal gland.

Water-soluble hormones affect target cells by binding to __________.

plasma membrane receptors

PRL is to ________ as ACTH is to ________.

prolactin; corticotropin

Oxytocin __________.

rises (in its concentration) during sexual arousal and peaks at orgasm in both sexes Submit

The hypothalamus controls secretion by the anterior pituitary by

secreting releasing and inhibiting factors into a tiny portal system. Submit

Which is a function of melatonin in humans?

sets circadian rhythms

Which structure secretes hormones involved in the stimulation and coordination of the immune response?

thymus

Glucocorticoids are released by the __________.

zona fasciculata of the adrenal cortex

A hormone that promotes glucose formation in the liver is

cortisol.

Name the two lobes of the pituitary gland. (Module 16.6A)

anterior lobe and posterior lobe

What other symptom is Tanya likely experiencing as a result of diabetes that accounts for her high level of thirst?

Increased urination

The amplification of the signal from a water-soluble hormone is achieved through an increase in _______.

Many cAMP can be generated as a second messenger to amplify the signal in response to hormone binding.

Secretory cells of the adenohypophysis release all of the following except

OXT.

The pituitary hormone that stimulates milk production by the mammary glands is

PRL

Increased levels of the hormone ________ will lead to increased levels of calcium ions in the blood.

PTH

What is the role of activated protein kinases?

Phosphorylation can activate different proteins causing the response of the cell to water-soluble hormone.

Which of the following is the best evidence that Tanya has Type 2 (not Type 1) diabetes mellitus?

She is 50-years old and out of shape

Choose which condition has all of the following symptoms: hypertension, hyperglycemia, and a "moon face."

Yes, a patient with Cushing's would have hypertension, increased blood glucose, and an unusual fat distribution on the face, known as a "moon face." These symptoms are due to increased levels of cortisol and can also be seen in patients after long periods of steroid treatment.

Which of the following are symptom(s) of pheochromocytoma?

Yes, due to the increase in epinephrine, heart rate would be increased and you would feel like your heart was pounding or racing.

Which of the following hormones is a part of the rapid response (rather than the prolonged response) to stress?

Yes, epinephrine is part of the immediate or rapid response to stress. Epinephrine is released from the adrenal medulla as a result of the increase in the sympathetic nervous system. In fact, the chromaffin cells in the adrenal medulla act like modified postganglionic neurons.

In response to stress, which of the following changes would happen?

Yes, insulin decreases plasma glucose and during stress we need an increase in plasma glucose as well as other body fuels. Therefore, insulin secretion would be decreased, in turn increasing plasma glucose.

The anterior lobe of the pituitary is also known as the

adenohypophysis.

Steroid hormones

bind to receptors in the nucleus of their target cells.

What thyroid hormone aids in calcium regulation? (Module 16.8A)

calcitonin

A hormone that can lower blood levels of calcium ion is

calcitonin.

The C cells of the thyroid gland produce

calcitonin.