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Example Questions
Example Question #2 : Other Endocrine Glands
The adrenal medulla is responsible for secreting which hormone?
Aldosterone
Corticotropin-releasing hormone
Epinephrine
Cortisol
Epinephrine
The adrenal medulla, derived from neural crest cells, is responsible for making and releasing epinephrine and norepinephrine. Epinephrine and norepinephrine are responsible for increasing heart rate and activating the sympathetic nervous system when released.
In contrast, the adrenal cortex is derived from mesoderm and releases steroid hormones like aldosterone and cortisol. Corticotropin-releasing hormone is made by the parvocellular neurons of the hypothalamus.
Example Question #31 : Glands
The adrenal medulla is responsible for secreting which of the following hormones?
Epinephrine
Growth hormone
Thyroid-stimulating hormone
Adrenocorticotropic hormone
Epinephrine
Epinephrine and norepinephrine are released by the neuroendocrine cells of the adrenal medulla. In times of stress and sympathetic nervous system activation, the adrenal medulla will release epinephrine to cause blood vessel constriction. These hormones allow for the "fight-or-flight" response.
In contrast, the adrenal cortex will secrete cortisol and other mineralcorticoids in response to long-term stress. These hormones are not involved in the fight-or-flight response, and rather serve to prepare the body to endure prolonged harsh conditions, such as dehydration, starvation, and extreme temperatures. Adrenocorticotropic hormone is released from the anterior pituitary to stimulate the adrenal cortex.
Growth hormone and thyroid-stimulating hormone do not interact with the adrenal gland.
Example Question #31 : Endocrine System
The hormone cortisol is synthesized in the __________ and the hormone aldosterone is synthesized in the __________.
adrenal cortex . . . adrenal cortex
adrenal medulla . . . adrenal cortex
adrenal cortex . . . adrenal medulla
adrenal medulla . . . adrenal medulla
adrenal cortex . . . adrenal cortex
Hormones cortisol and aldosterone are synthesized in the adrenal glands. Adrenal glands are made up of the adrenal cortex and the adrenal medulla. Adrenal medulla is involved in the synthesize of catecholamines (epinephrine and norepinephrine) whereas adrenal cortex synthesizes mineralocorticoids (aldosterone), glucocorticoids (cortisol), and androgens (testosterone, DHT, and DHEA).
Aldosterone is released upon stimulation from the renin-angiotensin system and serves to increase reabsorption of sodium in the collecting ducts of the kidney. Cortisol is released due to stress and serves to increase the metabolic rate.
Example Question #33 : Glands
Which of the following hormones is produced by the pituitary gland?
Antidiuretic hormone
Aldosterone
Luteinizing hormone
Thyroxine
Epinephrine
Luteinizing hormone
Luteinizing hormone is produced and secreted by the anterior pituitary gland.
Antidiuretic hormone is produced by the hypothalamus, but secreted by the posterior pituitary gland. Epinephrine is produced by the adrenal medulla; aldosterone is produced by the adrenal cortex. Thyroxine (T4) is produced by the thyroid.
Example Question #671 : Mcat Biological Sciences
A person who has over-functioning pancreatic alpha cells may display what clinical feature?
Constipation
Elevated glucose levels
Decreased glucose levels
Increased digestion
Elevated glucose levels
The pancreatic alpha cells produce the hormone glucagon, which is responsible for stimulating gluconeogenesis and glycogenolysis. Gluconeogenesis is de novo formation of glucose, while glycogenolysis is the breakdown of glycogen into glucose. An increase in glucagon production through hyperactive alpha cells will result in increased blood glucose levels, at least temporarily. In a healthy individual, this will be combatted by an increase in insulin production from the pancreatic beta cell.
Example Question #2 : Hormone Origins And Targets
The activity of which of the following increases when parathyroid hormone is released into the blood stream?
T-cell maturation
Osteocytes
Osteoclasts
Osteoblasts
The parathyroid gland
Osteoclasts
Parathyroid hormone causes calcium to be released from the bone into the blood stream, raising blood calcium levels. Osteoclasts reside in bone and are responsible for resorbing the hydroxyapatite matrix, releasing sequestered calcium into the blood.
Osteoblasts counter osteoclasts, building the hydroxyapatite matrix and sequestering calcium stores. Osteocytes are mostly involved in signaling. The parathyroid gland releases parathyroid hormone, but is not affected by the hormone itself. T-cell mature in the thyroid, and are not affected by parathyroid activity.
Example Question #2 : Hormones
Which hormone is responsible for stimulating glucocorticoid release from the adrenal cortex?
Prolactin
Adrenocorticotropic hormone
Thyroid-stimulating hormone
Growth hormone
Adrenocorticotropic hormone
Adrenocorticotropic hormone (ACTH) is released from the anterior pituitary, and is responsible for stimulating secretion of glucocorticoids from the adrenal cortex. While cortisol is the most common and physiologically relevant glucocorticoid, others may also be synthesized. Adrenocorticotropic hormone release is stimulated by stress.
Example Question #4 : Hormone Origins And Targets
The hypothalamus uses two specialized types of neuron to stimulate the pituitary. Magnocellular neurons carry hormones directly to the posterior pituitary. Parvocellular neurons secrete hormones into the hypophyseal portal system, where they are delivered to the anterior pituitary.
The magnocellular neurons of the hypothalamus are responsible for secreting which hormone?
Thyroid-stimulating hormone (TSH)
Oxytocin
Dopamine
Thyrotropin-releasing hormone (TRH)
Oxytocin
The hypothalamus is divided up into two parts: the magnocellular neurons and the parvocellular neurons. The magnocellular neurons synthesize antidiuretic hormone (ADH) and oxytocin, which are then transported to the posterior pituitary for secretion. The parvocellular neurons secrete hormones such as corticotropin-releasing hormone (CRH) and thyrotropin-releasing hormone (TRH), which are released into portal circulation to be transported to the anterior pituitary.
Example Question #5 : Hormone Origins And Targets
Which of the following statements concerning hormonal transport is true?
The thyroid hormones are able to move freely in the bloodstream
Pancreatic hormones are able to move freely through the bloodstream
Steroid hormones are able to move freely through the bloodstream
All hormones require chylomicrons in order to move through the bloodstream
Pancreatic hormones are able to move freely through the bloodstream
The type of transport that a hormone will have through the bloodstream depends on the type of hormone. Peptide hormones are polar and can move freely through the bloodstream, while lipid soluble hormones require a carrier protein in order to move through the blood. The pancreatic hormones, glucagon and insulin, are peptide hormones. This means they can move through the bloodstream without a carrier protein.
In contrast, steroid hormones are derived from cholesterol and thyroid hormones are derived from tyrosine. Both of these hormone classes are lipid soluble, and require transport proteins to travel through the blood. The hormone-protein unit is known as a chylomicron.
Example Question #1 : Hormones
When calcitonin is released into the blood stream, the activity of which cell type is increased the most?
Osteoblasts
Osteoclasts
Hydroxyapatite cells
Osteocytes
Erythropoietic stem cells
Osteoblasts
Calcitonin is a hormone secreted by the thyroid in response to increased blood calcium levels. It counteracts high blood calcium by stimulating the deposit of calcium into bone. Osteoblasts are the most active cells in building the hydroxyapatite matrix of bone, and would be most stimulated by the release of calcitonin.
Osteocytes are matured osteoblasts in the bond interior, and are more active in signaling and regulation than bond formation. Osteoclasts counteract osteoblasts and break down bone, usually in response to parathyroid hormone. Hydroxyapatite is the crystalline matrix encasing the bone cells, but is not a type of cell itself. Erythropoietic stem cells reside in the bone marrow and produce blood cells, but are not involved in calcium regulation.
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