Endocrine System

Which lobe of the pituitary is larger and secretes more hormones

Anterior pituitary

Although hormones influence activity in the neural and reproductive system, they do not influence the digestive system

False

Each of the body's blood-born hormones comes from the major endocrine glands, namely, the pineal, pituitary, thyroid, or adrenal glands

False

The reaction time for endocrine effects is generally measured in milliseconds

False

Which hormones are collectively called the gonadtropins

Follicle-stimulating hormone and luteinizing hormone

You are "shadowing" an endocrinologist who is examining a patient complaining of weakness, weight loss, and heat intolerance. The doctor points out the patient's obvious exophthalmos and asks for your diagnosis. What would you speculate is the patient's problem?

Hypersecretion of thyroid hormone

The hormones and neurotransmitters released by the endocrine and nervous systems are chemical substances referred to as

Ligands

Which type of hormone requires a carrier protein in the blood

Lipid-soluble hormone

Compared to the nervous system the endocrine system has

More widespread and long-lasting effects

In which order would blood flow through these structures as it travels from the hypothalamus to the pituitary gland

Primary plexus, hypophyseal portal veins, Secondary plexus

Which is not a characteristic of endocrine system

Recovery time: rapid, immediate return to prestimulation level

Among their many functions, hormones regulate blood volume, cellular concentration, and number of platelets

True

The liver contains endocrine cells

True

When the follicular cells of the thyroid are stimulated to secrete TH, they take up TH precursors from the inside of the follicle, transport and enzymatically modify them within a lysosome, and then release TH to the blood

True

The term down-regulation refers to the process by which

a cell decreases the number of receptors it has for a hormone

The release of hormones from the adrenal cortex is stimulated by

adrenocorticotropic hormone

Glucagon and insulin work ___ on blood glucose levels

antagonistically

Thyroid-stimulating hormone is secreted by

anterior pituitary, and it targets follicular cells of the thyroid gland

Eicosanoids are synthesized from

arachidonic acid

Endocrine glands

are ductless glands are the organs of the endocrine system secrete hormones directly into the bloodstream help maintain homeostasis

The hormones that come from the posterior pituitary

are synthesized in the hypothalamus and are released from the posterior pituitary when nerve signals arrive

When eicosanoids bring about cellular changes within the cells from which they were formed, the process is called ____ stimulation

autocrine

Lipid-soluble hormones, such as progesterone, exert their effects by forming hormone-receptor complexes that

bind to DNA and initiate transcription

Modified amino acids that act as hormones are referred to as ___ amines

biogenic

Thyroid hormone is somewhat unique in that it is a

biogenic amine that is lipid-soluble

Aldosterone release can be triggered by the presence of blood-borne messenger angiotensin II or by low levels of sodium, and so its secretion regulation is said to be

both hormonal and humoral

Steroid hormones are lipids, derived from

cholesterol

Until thyroid hormone needs to be secreted, precursors to it are stored in a viscous, protein-rich fluid within the center of thyroid follicles. This viscous fluid is known as ___

colloid

The hypothalamic hormone that triggers the release of adrenocorticotropic hormone (ACTH) is

corticotropin-releasing hormone (CRH)

In most of its target cells, cortisol ___ glucose uptake and ___ protein metabolism

decreases, increases

Once a structure is fully grown and mature, it will probably

down-regulate its receptors for growth hormone, as it no longer needs to continue to grow at a fast rate

Intracellular signaling within target cells are organized such that

each step allows for amplification of the signal where one molecule can activate many

Like all other hormone transport proteins, albumin is highly specific in terms of which hormone it carries through the blood.

false

Like proteins eicosanoids are synthesized on ribosomes in a process that involves transcription and translation

false

Steroids, peptides, and nucleic acids are the three classes of hormones

false

The function of each of the regulatory hormones of the hypothalamus is to trigger to the release of a tropic hormone from the pituitary

false

Follicle-stimulating hormone is a

glycoprotein

Parathyroid hormone release depends on blood levels of calcium. Such as endocrine reflex is said to be initiated by

humoral stimulation

Within the infundibulum, the axons from neurons extending into the posterior pituitary are known as the

hypothalamo-hypophyseal tract

The part of the brain that functions as a master control center of the endocrine system is the

hypothalamus

The thyroid gland is located

immediately anterior to the trachea

Damage to the liver might impair enzymatic degradation of some hormones. The levels of such hormones in the blood would therefore be expected to

increase

thyroid hormone's effects are to

increase metabolic rate and body temperature by increasing protein synthesis in target cells

Exercise causes a ___ in GH levels; a rise in amino acid levels or decrease in glucose levels cause a ___ in GH levels

increase, increase

The pituitary gland is located ___ to the hypothalamus and is connected by the ___

inferior, infundibulum

Oxytocin results in more forceful smooth muscle contractions in the uterus by causing target cells to increase production of

inositol triphosphate

which hormone induces its target cells to take up glucose, thereby lowering blood glucose levels

insulin

Lipophilic hormones bind to ___ receptors of target cells

intracellular

cortisol bind to ___ receptors and has the effect of ___ blood glucose levels

intracellular, raising

As someone starts to develop in puberty, most cells in their reproductive organs are probably starting to express

more receptors for sex hormones

Where are the target cells for follicle-stimulating hormone

ovaries and testes

The two hormones released from the posterior pituitary are

oxytocin and antidiuretic hormone

In addition to secreting hormones, the pancreas also produces

pancreatic juice

When a chemical messenger helps initiate an inflammatory response by causing cellular changes in neighboring cells, it is demonstrating ___ signaling.

paracrine

the hormone oxytocin is synthesized in the

paraventricular nucleus

Two regions of the hypothalamus that are associated with the posterior pituitary are the

paraventricular nucleus and supraoptic nucleus

When the activity of one hormone requires that of a second hormone, the interaction is said to be

permissive

In the signal transduction pathway that results in the formation of inositol triphosphate, the G protein directly activates

phospholipase C

The small, cone-shaped gland that is in the epithalamus of the brain is the ___ gland

pineal

Parathyroid glands are located

posterior to the thyroid gland

The adrenal glands are located ___ to the parietal peritoneum and each has a cortex of a ___ color

posterior, yellow

which is no a tropic hormone

prolactin

Within the adenylate cyclase signal transduction pathways of target cells, cAMP activates

protein kinase

Most hormones are made of chains of amino acids and are therefore

proteins

What is the function of the mineralocorticoids secreted by the adrenal gland

regulate electrolyte concentration in body fluids

Growth hormone is secreted by ___ cells in the anterior pituitary

somatotropic

the primary function of the adrenocorticotropic hormone (ACTH) is to

stimulate glucocorticoid release from the adrenal glands

When the effects of one hormone reinforce the activity of another hormone on the same target cell, the interaction is said to be

synergistic

The binding of a hormone and a carrier protein is ___; a very ___ fraction of such a hormone in the blood is bound to a carrier at any one point in time

temporary; large

When the effects of water-soluble hormones on their target cells are considered, the hormone itself is

the first messenger

Generally, the shorter the half-life of a hormone

the more frequently it must be replaced

The release of hormones from the adrenal medulla is stimulated by

the sympathetic division of the autonomic nervous system

The half-life of a hormone is

the time necessary to reduce the hormone concentration

Thyroid hormone synthesis involves secretion of glycoprotein called ___ by the follicular cells

thyroglobulin

Eicosanoids are primary type of local horone

true

Growth hormone releasing hormone (GHRH) is one of the regulatory hormones released by the hypothalamus that acts on the pituitary

true

Increasing levels of cortisol inhibit the release of corticotropin-releasing hormone

true

The pars distalis is part of the adenohypohysis

true

Reduced hormone concentration in the blood often causes target cells to

up-regulate receptors in order to increase cell sensitivity

Protein hormones

water-soluble

Where is the pituitary gland located

within the sella turcica of the sphenoid bone

Which region of the adrenal cortex synthesizes glucocorticoids

zona fasciculata

A G protein is

A molecule that binds a guanine nucleotide and helps transduce a signal inside a target cell

which is not a cell type found in the pancreatic islets

A. Alpha cell B. Delta cell C. Beta cell D. F cell **E. C cell**

Which hormone group is not secreted by the adrenal cortex

A. Corticosteroids B. Glucocorticoids C. Mineralocorticoids D. Gonadocorticoids **E. No exceptions; all choices are secreted by the adrenal cortex**

which is not correct regarding growth hormone (GH)

A. GH affects most body cells. B. GH stimulates cell growth and mitosis. C. GH is also known as somatotropin. **D. GH stimulates the kidney to secrete somatomedin.** E. GH is a tropic hormone.

which is not correct regarding the pancreas

A. It is located posterior to the stomach, between the small intestine and the spleen. B. It is a heterocrine, or mixed, gland. C. It is elongated in shape, spongy, and nodular. D. The majority of cells in the pancreas are pancreatic acini. **E. It does not begin to secrete its hormones until puberty.**

Which is not true about the thyroid gland

A. It requires iodine to synthesize thyroid hormone. B. It is located on the anterior surface of the trachea, inferior to the thyroid cartilage. **C. It has two lobes connected by a central portion called the commissure.** D. It secretes thyroid hormone in response to stimulation by TSH. E. An enlargement of the thyroid gland is called a goiter