Lecture Endocrine System Flashcards
Which of the following occurs in situations where more than one hormone produces the same effects at the target cell & their effects are amplified?
Synergism
Which of the following hormones helps the body avoid dehydration & water overload?
Anti-diuretic Hormone (ADH)
The stimuli causing endocrine glands to secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients are called________.
Humoral Stimuli
T or F: Hyperparathyroidism is a rare condition where the bones soften and deform.
True
Name the steps in which the body maintains homeostasis when blood glucose levels fall.
- Stimulus = low blood glucose
- Endocrine cells = cells in the pancreas
- Hormone = Glucagon
- Target cells = liver cells
- Response = glycogen breakdown; glucose released into blood
Which of the following is NOT a major types of stimulus that triggers endocrine glads to manufacture and release hormones? Hormonal Neural Enzymatic Humoral
Enzymatic
Which of the following best describes gluconeogenesis?
- synthesis of glucose from noncarbohydrate sources
- conversion of glucose to fat
- creation of glycogen from glucose
- breakdown of glycogen into glucose
Synthesis of glucose from noncarbohydrate sources
What stimuli causes testosterone production?
Hormonal stimulus
What stimulus causes epinephrine production?
Neural stimulus
What stimulus causes aldosterone production?
Humoral and/or hormonal stimulus
What stimulus causes parathyroid hormone production?
Humoral stimulus
Which of the following is NOT a homeostatic imbalance related to under-activity of the thyroid gland?
Endemic goiter
Graves’ disease
Cretinism
Myxedema
Graves’ Disease
What tropic hormone stimulates cortisol from the adrenal gland?
Adrenocorticotropic hormone (ACTH)
What is the function of the ventral hypothalamic neurons?
Control secretion of thyroid stimulating hormone (TSH)
Neurohormones from the ventral hypothalamic neurons, known as releasing (RH) and inhibiting (IH) hormones, control the release of anterior pituitary hormones such as ACTH & TSH
Insulin-like growth factors (IGFs) are intermediary hormones stimulated by which of the following hormones?
Growth hormone (GH)
What hormone is regulated by a neuroendocrine (“letdown”) reflex?
Oxytocin
Suckling of infant (or stretching of the uterus) increases release of oxytocin, which caused the milk let-down effect (or increased uterine contractions)
Where is antidiuretic hormone (ADH) also known as vasopressin, synthesized?
Hypothalamus
Synthesized in hypothalamus
Stored in posterior pituitary
What is the most important regulatory factor controlling the circulating levels of thyroid hormone?
Negative Feedback
Which of the following glands is found atop the kidneys?
Adrenal
Which of the following homeostatic imbalances is characterized by persistent elevated blood glucose levels dramatic losses in muscles & bone protein, and water and salt retention leading to hypertension and edema?
Cushing’s syndrome
Hormones often cause a cell to elicit multiple responses; this is because _________.
During protein kinase activation, enzymes phosphorylate many other enzymes
What hormones are produced by the posterior pituitary?
None!
What triggers the release of glucagon?
A decrease in blood glucose levels
______ is the situation when one hormone cannot exert its full effects without another hormone being present.
Permissiveness
Which hormone is the body’s major metabolic hormone?
Thyroid hormone
You eat a sugary snack. What happens next?
- Blood glucose becomes high
- Pancreas releases insulin
- Insulin binds to receptors on target cells
- Cells take in glucose
- Blood glucose returns to normal
Which hormone mainly serves to stimulate milk production by the breasts?
Prolactin
Two adrenal glands make hormones that are essential for life. However, in adrenogenital syndrome, females develop a beard & masculine pattern of body hair distribution; this occurs due to ________.
Lack of enzymes the adrenal glad needs to make cortisol & aldosterone
Congenital adrenal hyperplasia is a condition in which the body lacks the essential enzyme the adrenal gland needs; at the same time the body produces more androgen (sex hormone) causing male characteristics to appear early/inapppropriately
Chemical substances secreted by cells into extracellular fluids & that regulate the metabolic function of other cells in the body are called______.
Hormones
Hormones that regulate the secretory action of other endocrine glands are called_______.
Tropins
Which of the following is NOT a steroid-based hormone?
Epinephrine
Aldosterone
Estrogen
Cortisone
Epinephrine
Name the class of hormones that corresponds with zona glomerulosa.
Mineralcorticoids
Which pancreatic hormone functions to lower blood glucose levels?
Insuline
What is the primary function of hormones?
Alter cell activity
By altering plasma membrane permeability, or membrane potential, stimulating synthesis of enzymes, or regulating molecules, activating or deactivating enzymes, inducing secretory activity or stimulating mitosis
Which hormone regulates blood calcium ion levels?
Parathyroid Hormone
One can predict that a person suffering from diabetes mellitus would probably have _______.
increased secretion of ADH
ADH is secreted in response to high blood osmolarity (too high solutes/water) in blood; ADH functions to increase the resorption of water by kidneys, which dilutes the blood
Cellular responses to hormones that initiate second-messenger systems include______.
Possible activation of several different second-messenger systems
Which organ is responsible for synthesizing ANP?
Heart
The second-messenger mechanism of hormone action operates by ______.
Binding to specific receptors and employing the services of G proteins and cAMP
The stimuli causing endocrine glands to secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients are called ______.
Humoral Stimuli
What hormone is part of the rapid response (rather than prolonged) response to stress?
Epinephrine
Released from adrenal medulla as a result of the increase in the sympathetic nervous system
In response to stress, which of the following changes would happen?
- Decreased insulin secretion
- Decreased sweating
- Decreased cardiac output
- Decreased or difficulty breathing
Decreased insulin secretion
Insulin decreases plasma glucose and during stress we need an increase in plasma glucose as well as other body fuels
What is a symptom of pheochromocytoma?
Heart palpitations
Due to increase in epinephrine; heart rate would increase
Which condition has all of the following symptoms:
hypertension
hyperglycemia
“moon face”
Cushing’s Disease
Symptoms due to increased levels of cortisol & can also be seen in patients after long periods of steroid treatment
What hormone also aids in the stress response by promoting water retention and acting as a vasoconstrictor?
ADH (vasopressin)
What antagonist hormone regulates blood calcium levels?
Parathyroid hormone & calcitonin
Which is NOT a property of endocrine glands?
- have ducts
- drain vascularly
- drain lymphatically
- produce hormones
Have ducts
T or F: Direct gene activation involves a second-messenger system.
False
A 25-year-old male was admitted to the medical/surgical unit with a blood glucose level of 600 mg/dl. On assessment, the nurse observed that his breathing was deep & rapid, his breath smelled of acetone. His face was flushed, his skin was dry, and his pH was low. What is the diagnosis and what physiological response is occurring?
Diabetes mellitus; nervous system responds by initiating rapid deep breathing to blow off carbon dioxide from the blood & increase pH
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
The amplification of the signal from water-soluble hormone is achieved through an increase in _____.
cAMP
Water-soluble hormones affect target cells by binding to______.
Plasma membrane receptors
Water-soluble hormones bind to specific receptors in plasma membrane; vs. steroid hormones bind to cytoplasmic receptors
How do endocrine hormones reach their target cells?
Hormones are transported through the blood stream to target cells
What is the role of activated protein kinases?
Phosphorylate proteins
Phosphorylation can activate different proteins causing the response of the cell to water-soluble hormone
Cyclic AMP is degraded by____.
Phosphodiesterase
The parathyroid glands maintain adequate levels of blood calcium. This is accomplished through ______.
Targeting the bone & activating osteoclasts so that calcium will be released
T or F: Up-regulation involves the loss of receptors and prevents the target cells from overreacting to persistently high hormone levels.
False
T or F: Hormones are long-distance chemical signals that travel in blood or lymph throughout the body.
True
What hormone stimulates the adrenal cortex to release glucocorticoids that help the body to resist stressors?
Adrenocorticotropic Hormone
Cushing’s syndrome and aldosteronism have the same effects on_____.
Blood pressure
What is required for the production of anterior pituitary gland hormones?
Hormonal stimuli
List the correct steps of cAMP signaling.
- water soluble hormone binds to receptor
- receptor activates G protein
- G protein activates adenylate cyclase
- Adenylate cyclase generates cAMP
- cAMP activates protein kinases
Thyroid hormone (a small iodinated amine) enters target cells in a manner similar to ____.
Steroid hormones; because both diffuse easily into target cells
T or F: Both “turn on” factors (hormonal, humoral, and neural stimuli) and “turn off” factors (feedback inhibition & others) may be modulated by the activity of the nervous system.
True
Which of the following has intracellular receptors?
Epinephrine
Cortisol
Insulin
Cortisol
Lipid-soluble steroid; same as thyroid hormones
What is the mechanism of action of lipid-soluble hormones?
Activation of genes, which increases protein synthesis in the cell
Diffuse into nucleus/cytoplasm & move into nucleus where they affect transcription/translation
After a lipid-soluble hormone is bound to its intracellular receptor, what does the hormone complex do?
Acts as a transcription factor & binds to DNA activating the gene
Then mRNA is synthesized
Which hormone’s receptor is always bound to DNA, even when the receptor is empty?
Thyroid hormone
What keeps intracellular receptors from binding to DNA before a hormone binds to the receptor?
Chaperone proteins (chaperonins)
Chaperone blocks the DNA binding site until hormone binds at the hormone binding site
T or F: Major hormones circulate to virtually all tissues.
True
What hormone is essential to our ability to deal with stress?
Glucocorticoids
