BIO-169 Chapter 16

Cushing's disease results from an excess of

Glucocorticoids

Hormones that regulate the male and female reproductive organs are collectively called

Gonadotropins

The pituitary hormone that stimulates cell growth and replication by accelerating protein synthesis is

Growth hormone

Extracellular membrane receptors are used by which types of hormones?

leukotrienes, catecholamines, peptide hormones, prostaglandins

A rise in cortisol would NOT cause an increase in

ACTH levels

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

The posterior pituitary gland secretes

ADH (antidiuretic hormone)

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

ADH (vasopressin)

What is the mechanism of action of lipid-soluble hormones?

Activation of genes, which increases protein synthesis in the cell

After a lipid-soluble hormone is bound to its intracellular receptor, what does the hormone complex do?

Acts as a transcription factor and binds to DNA, activating a gene

The anterior lobe of the pituitary is also known as the

Adenohypophysis

What tropic hormone stimulates cortisol from the adrenal gland?

Adrenocorticotropic hormone (ACTH)

A hormone that helps to regulate the sodium ion content of the body is

Aldosterone

Hormones can be divided into different groups based on their chemistry. These groups are:

Amino acid derivatives, eicosanoids, peptides, steroids

An activated G protein CAN'T trigger:

An increase ATP production.

Two hormones that have opposing effects are called

Antagonists

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

Heart palpitations

The body's tendency to maintain relatively constant internal conditions is called

Homeostasis

________ are chemical messengers that are released in one tissue and transported in the bloodstream to alter the activities of specific cells in other tissues.

Hormones

How do endocrine hormones reach their target cells?

Hormones are transported through the blood stream to target cells.

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

Hormones; neurotransmitters

During the alarm phase of the general adaptation syndrome (GAS), there is

Mobilization of energy reserves

What is the most important regulatory factor controlling the circulating levels of thyroid hormone?

Negative feedback

Which hormone is regulated by a neuroendocrine ("letdown") reflex?

Oxytocin

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

PTH

Which cells of the thyroid produce calcitonin?

Parafollicular or C cells

A 22-year-old female is given the results of her blood test and she notices that her calcium levels are high. Which hormone is most likely to be elevated?

Parathyroid hormone

Cyclic AMP is degraded by __________.

Phosphodiesterase

Which enzyme is important in the deactivation of cAMP and termination of signaling?

Phosphodiesterase

Which intracellular substance degrades cAMP, thus inactivating the response to a hormone?

Phosphodiesterase

What is the role of activated protein kinases?

Phosphorylate proteins.

What structure secretes melatonin?

Pineal gland

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

Plasma membrane receptors

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

The G protein aids in the activation of a second messenger.

When blood glucose levels are low

The pancreas releases glucagon, which eventually causes blood glucose levels to increase.

When blood glucose levels are high

The pancreas releases insulin

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

Cushing's disease

The zona glomerulosa of the adrenal cortex produces

Mineralocorticoids

Which is the correct order of events for hormones activating Gs proteins?

- Activation of G protein - Binding of GTP - Activation of adenylate cyclase - Conversion of ATP to cAMP

Events of cAMP signaling

1. Water-soluble hormone binds receptor 2. Receptor activates G protein 3. G protein activates adenylate cyclase 4. Adenylate cyclase generates cAMP 5. cAMP activates protein kinases

The pineal gland is NOT

A component of the hypothalamus

Which adrenergic receptor increases cAMP levels?

Beta receptors

Steroid hormones...

Bind to receptors in the nucleus of their target cells.

In ________ diabetes, glucose levels remain higher than normal.

Both type 1 and type 2

What keeps intracellular receptors from binding to DNA before a hormone binds to the receptor?

Chaperone proteins (chaperonins)

Peptide hormones are

Composed of amino acids

What is the function of the ventral hypothalamic neurons?

Control secretion of thyroid stimulating hormone (TSH)

Which hormone has intracellular receptors?

Cortisol

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

Decreased insulin secretion

Inability of the pancreas to produce insulin results in

Diabetes mellitus

The hypophyseal portal system

Does not transport ADH and oxytocin Carries neurosecretions to the anterior lobe of the pituitary Has two capillary plexuses connected by short veins.

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

Epinephrine

____________ increases and prolongs effects of the sympathetic nervous system

Epinephrine

Which hormone increases production of red blood cells?

Erythropoietin

The ovaries secrete ________ when stimulated by FSH.

Estrogen

The pituitary hormone that promotes egg development in ovaries and sperm development in testes is

FSH

Insulin-like growth factors (IGFs) are intermediary hormones stimulated by which of the following hormones?

GH (growth hormone)

Excess secretion of growth hormone during early development will cause:

Gigantism

A person with untreated diabetes will NOT experience

Hypoglycemia

The most complex endocrine responses that integrate the nervous and endocrine system involve the

Hypothalamus

Where is antidiuretic hormone (ADH) produced?

Hypothalamus

Where is antidiuretic hormone (ADH), also known as vasopressin, synthesized?

Hypothalamus

Which second messenger causes the release of calcium from the endoplasmic reticulum?

IP3

The hypothalamus controls the anterior pituitary using which mechanism?

Indirectly by secreting specific regulatory hormones

The pancreatic hormone that causes blood sugar levels to fall is

Insulin

The beta cells of the pancreatic islets produce ________ which ________ blood sugar.

Insulin; lowers

Hormones that produce different but complementary results are called

Integrative

What cells in the body respond to glucagon by breaking down glycogen and releasing glucose?

Liver cells

Body cells that respond to insulin include

Liver cells, as well as most other cells of the body.

What might occur in an overdose of insulin?

Low blood glucose

Proper growth does NOT require which hormone?

MSH

The hormone oxytocin does NOT

Respond to osmoreceptors

The hypothalamus controls secretion by the anterior pituitary by

Secreting releasing and inhibiting factors into a tiny portal system.

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

Steroid hormones are hydrophobic and can pass through the lipid bilayer.

The ________ gland sits along the superior border of the kidney.

Suprarenal

Two hormones that have additive effects are called

Synergists

A liver cell responds to insulin by

Taking in glucose and converting it to glycogen.

Which hormone's receptor is always bound to DNA, even when the receptor is empty?

Thyroid hormone

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

Thyroid hormones

The hormone that plays a pivotal role in setting the metabolic rate and thus impacting body temperature is

Thyroxine

Which hormone is produced by the thyroid gland?

Thyroxine

The condition known as goiter can result from:

Too little iodine in the diet

The posterior lobe of the pituitary contains axons of neuron cell bodies located in the hypothalamus.

True

In ________ diabetes, no insulin is produced.

Type 1

In ________ diabetes, target cells do not respond normally to insulin.

Type 2

Growth factor hormones, such as insulin, bind to which type of receptor?

Tyrosine kinase receptors

What type of hormones bind to receptors located on the cell membrane?

Water-soluble hormones, such as insulin and epinephrine

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

cAMP in the cytoplasm