How can we help?

You can also find more resources in our Help Center.

91 terms

Endocrine System

STUDY
PLAY
Hyposecretion of the pancreas
Diabetes Mellitus
Hyposecretion of growth hormone
Pituitary Dwarfism
Hyposecretion of the adrenal cortex
Addison's Disease
Hypersecretion of growth hormone
Acromegaly
Hyposecretion of the thyroid in infants
Cretinism
Hypersecretion of the adrenal cortex
Cushing's Disease
The gland that controls the fight-or-flight reaction
Adrenal Medulla
Produces hormones that regulate glucose levels in the body
Pancreas
Produces the body's major metabolic hormones
Thyroid
Produces a hormone that controls blood levels of calcium and potassium by their removal from bone tissue
Parathyroid
The size and shape of a pea; produces hormones that stimulate other endocrine glands
Hypophysis
In humans, melatonin may inhibit sexual maturation
True
Follicle cells of the thyroid gland produce thyroglobulin, while follicle cells of the parathyroid produce calcitonin
False
The thyroid gland is embedded in the parathyroid tissue
False
The prime metabolic effect of cortisol is gluconeogenesis
True
The beta cells are the pancreatic islet cells that produce insulin
True
Peptide hormones enter the target cells and elicit a response by mediating neurotransmitter effects
False
Calcitonin is a peptide hormone that has destructive effects on the skeletal system
False
Aldosterone is the most potent mineralocorticoid produced in the adrenals but the least abundant
False
Atrial natriuretic peptide is a hormone that controls blood pressure in part by increasing the urinary excretion of sodium
True
While glucagon is a small polypeptide, it is nevertheless very potent in its regulatory effects
True
The thyroid gland is a large gland that controls metabolic functions throughout the life of an individual
True
The antagonistic hormones that regulate the blood calcium level are calcitonin-parathormone
True
Many hormones synthesized in the gastrointestinal tract are chemically identical to brain neurotransmitters
True
All of the following hormones are secreted by the adenohypophysis: ACTH, FSH, and LH
True
Iodine is an essential element required for the synthesis of thyroxine
True
The endocrine gland that is probably malfunctioning if a person has a high metabolic rate is the parathyroid
False
Growth hormone always exerts its influence by targeting other endocrine glands to produce hormones
False
Diabetes insipidus and diabetes mellitus are both caused by a genetic mutation involving the synthesis of insulin
False
The stimulus for calcitonin release is usually excessive amounts of growth hormone synthesis
False
Glucocorticoids are steroid hormones that usually enhance the immune responses when an individual is suffering from severe stress
False
Direct gene activation involves a second-messenger system
False
All peptide hormone synthesis requires gene activation that produces mRNA
True
The hormone that raises blood sugar levels is insulin
False
All adenohypophyseal hormones except GH affect their target cells via a cyclic AMP second-messenger
True
The endocrine structure that develops from the nervous system is the anterior pituitary
False
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
ACTH stimulates the adrenal cortex to release corticosteroid hormones
True
LH is also referred to as a gonadotropin
True
The only known effect of prolactin in humans is to produce impotence in males
False
Oxytocin is a strong stimulant of uterine contractions
True
Gluconeogenesis occurs in the liver due to the action of ________.
Cortisol
ADH ________.
is inhibited by alcohol
Thyroid hormone exerts its influence by ________.
entering some cells and binding to intracellular receptors within the nuclei.
Gonadocorticoid(s) ________.
production by the adrenal gland is insignificant compared with sex hormone release from the gonads during late puberty
Sometimes prolonged excessive exposure to high hormone concentrations causes a phenomenon known as ________.
down-regulation
Which of the following is not a change that may be caused by hormonal stimulus?
direct control of the nervous system
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
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
The neurohypophysis or 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
Insulin, a small (51-amino-acid) protein, is synthesized by the beta cells of the pancreas. This hormone is released ________.
when the body's glucose level rises
Steroid hormones exert their action by ________.
entering the nucleus of a cell and initiating or altering the expression of a gene
Normal development of the immune response is due in part to hormones produced by the ________.
Thymus gland
The second-messenger mechanism of hormone action operates by ________.
binding to specific receptors and employing the services of G proteins and cAMP
Hormones often cause a cell to elicit multiple responses; this is because ________.
during protein kinase activation, enzymes phosphorylate many other enzymes
Cells that respond to peptide hormones usually do so through a sequence of biochemical reactions involving receptor and kinase activation. In order for cells to respond, it is necessary for first and second messengers to communicate. This is possible because ________.
G protein acts as the link between first and second messengers
Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ________.
steroid hormones, because both diffuse easily into target cells
When it becomes necessary to enlist the fight-or-flight response, a hormone that is released during the alarm phase of the general adaptation syndrome is ________.
Epinephrine
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
The major targets of growth hormone are ________.
bones and skeletal muscles
The parathyroid glands maintain adequate levels of blood calcium. This is accomplished through ________.
targeting the bone and activating osteoclasts so that calcium will be released
Which organ is responsible for synthesizing ANP?
Heart
Mineralocorticoid is to aldosterone as glucocorticoid is to ________.
Cortisol
Virtually all of the protein or amino acid-based hormones exert their effects through intracellular ________.
Second messengers
Leptin is secreted by ________.
Adipocytes
The most important regulator of electrolyte concentrations in extracellular fluids is ________.
Aldosterone
Which of the following is not a steroid-based hormone?
Epinephrine
Which of the following does not act as a second messenger in second-messenger systems of hormone action?
Calmodulin
Select the correct statement about the structure or function of chemical messengers.
An amino acid derivative can be a hormone
Which of the following would be associated with the action of steroids on cells?
a hormone-receptor complex that interacts directly with the cell's DNA
Cellular responses to hormones that initiate second-messenger systems include ________.
possible activation of several different second-messenger systems
Regulating hormones from the hypothalamus ________.
first enter into the hypophyseal portal system
ACTH ________.
secretion is regulated by a hypothalamic secretion
Which of the following is true about calcium homeostasis?
Parathyroid hormone is the single most important regulator of calcium levels in the blood
Which of the following is not a category of endocrine gland stimulus?
Enzyme
Aldosterone ________.
functions to increase sodium reabsorption
The only amine hormone to act like a steroid is ________.
Thyroid Hormone
Which organ does not have hormone production?
Liver
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
Eicosanoids do not include ________.
Hydrocortisones
A man has been told that he is not synthesizing enough follicle-stimulating hormone (FSH), and for this reason he may be unable to father a child. Choose the correct statement to explain this problem.
FSH stimulates sperm production in the testes
Which of the following organs is affected by thyroid hormone in adults?
Liver
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 effect a response
Factors that inhibit TSH release do not include ________.
excessively high blood iodine concentrations
Glucocorticoids enable the body to deal appropriately with stress. They accomplish this by ________.
increasing blood glucose, fatty acid, and amino acid levels and enhancing blood pressure
Chemical substances secreted by cells into the extracellular fluids that regulate the metabolic function of other cells in the body are called ________.
Hormones
What ion is sometimes used as a second messenger of amino acid-base hormones?
Calcium
The hypothalamic-hypophyseal tract ________.
is partly contained within the infundibulum
Tropic hormones ________.
include ACTH and TSH
Growth hormone ________.
promotes long bone growth during the formative years
Oxytocin ________.
release is an example of a positive feedback control mechanism