Title: The Endocrine System
Course: Question Banks

Q: The cells, tissues, and organs that secrete ________ make up the endocrine system.
- neurotransmitters (Incorrect. Neurotransmitters are chemical messengers that enable neurotransmission.)
- cerebrospinal fluid (CSF) (Incorrect. CSF is produced by a tissue called choroid plexus in the nervous system.)
- hormones (Correct.)
A: hormones

Q: Most lipid hormones are derived from ________.
- tryptophan (Incorrect. Tryptophan is an amino acid-derived hormone.)
- peptides (Incorrect. Peptide hormones are a separate class of hormones than lipid hormones.)
- cholesterol (Correct.)
A: cholesterol

Q: Steroid hormones are the primary class of ________ hormones.
- amino acid-derived (Incorrect. Steroids are a lipid-derived hormone.)
- peptide (Incorrect. Steroids are a lipid-derived hormone.)
- lipid-derived (Correct.)
A: lipid-derived

Q: ________ is an example of an amino acid-derived hormone.
- Testosterone (Incorrect. This is an example of a lipid-derived hormone.)
- Insulin (Incorrect. This is an example of a peptide hormone.)
- Melatonin (Correct.)
A: Melatonin

Q: Most amino acid-derived hormones are derived from ________.
- cholesterol (Incorrect. Most lipid hormones are derived from cholesterol.)
- estrogen (Incorrect. Estrogen is a lipid-derived hormone.)
- tyrosine and tryptophan (Correct.)
A: tyrosine and tryptophan

Q: The hormone________ is derived from tyrosine.
- melatonin (Incorrect. Melatonin is an example of a hormone derived from tryptophan.)
- insulin (Incorrect. This is a peptide hormone.)
- epinephrine (Correct.)
A: epinephrine

Q: ________ is an example of a peptide hormone
- Testosterone (Incorrect. This is an example of a lipid-derived hormone.)
- Melatonin (Incorrect. This is an example of an amino acid-derived hormone.)
- Oxytocin (Correct.)
A: Oxytocin

Q: Peptide hormones are made up of ________.
- ketones or alcohols (Incorrect. The primary class of lipid hormones is the steroid hormones. Chemically, these hormones are ketones or alcohols.)
- tryptophan (Incorrect. The amino acid-derived hormones are derived from the amino acids tyrosine and tryptophan.)
- polypeptide chains (Correct. The peptide hormones include molecules that are short polypeptide chains (chain of amino acids).)
A: polypeptide chains

Q: Growth hormones are an example of what type of hormone?
- amino acid-derived hormone (Incorrect. Growth hormones are small proteins, much larger than those derived from cholesterol or amino acids)
- lipid-derived hormone (Incorrect.)
- peptide hormone (Correct.)
A: peptide hormone

Q: Hormone production and release are primarily controlled by ________.
- positive feedback (Incorrect. Hormone levels are primarily controlled through negative feedback, in which rising levels of a hormone inhibit its further release.)
- immune regulation (Incorrect. Hormone levels are primarily controlled through negative feedback, in which rising levels of a hormone inhibit its further release.)
- negative feedback (Correct. Hormone levels are primarily controlled through negative feedback, in which rising levels of a hormone inhibit its further release.)
A: negative feedback

Q: What does the term humoral stimuli refer to?
- the release of a hormone in response to another hormone (Incorrect. This is hormonal stimuli, humoral stimulus is the control of hormone release in response to changes in extracellular fluids.)
- the nervous system directly stimulating release of hormones (Incorrect. This is neural stimuli, humoral stimulus is the control of hormone release in response to changes in extracellular fluids.)
- the control of hormone release in response to changes in extracellular fluids (Correct.)
A: the control of hormone release in response to changes in extracellular fluids

Q: Direct stimulation of hormone release by the nervous system is referred to as ________.
- humoral stimuli (Incorrect. Humoral stimuli is the control of hormone release in response to changes in extracellular fluids.)
- hormonal stimuli (Incorrect. Hormonal stimuli is when a hormone stimulates the release of another hormone.)
- neural stimuli (Correct.)
A: neural stimuli

Q: Hormones mediate changes in target cells by ________.
- depolarizing the membrane (Incorrect. Membrane depolarization is when the negative internal charge of the cell temporarily becomes less negative such as with an action potential.)
- blocking the binding of specific hormone receptors (Incorrect. Hormones circulate throughout the body and come into contact with many different cell types but they only affect cells that possess the necessary receptors.)
- binding to specific hormone receptors (Correct.)
A: binding to specific hormone receptors

Q: In up-regulation, the number of receptors ________in response to rising hormone levels
- decreases (Incorrect. The number of receptors increase in response to rising hormone levels in up-regulation.)
- stays the same (Incorrect. The number of receptors increase in response to rising hormone levels in up-regulation.)
- increases (Correct.)
A: increases

Q: In down-regulation, the number of receptors decrease in response to ________ hormone levels.
- declining (Incorrect. When the number of receptors decreases in response to rising hormones levels, cellular activity is reduced.)
- unchanged (Incorrect. When the number of receptors decreases in response to rising hormones levels, cellular activity is reduced.)
- rising (Correct.)
A: rising

Q: ________hormones such as steroid hormones diffuse across the membranes of the endocrine cell.
- Peptide (Incorrect. Peptide hormones are not lipid soluble.)
- Amino acid-derived (Incorrect. Growth hormones are small proteins, much larger than those derived from cholesterol or amino acids and are not lipid soluble.)
- Lipid-derived (Correct. Lipid-derived hormones are soluble and can therefore diffuse across the membranes of cells.)
A: Lipid-derived

Q: The ________ induced by the steroid hormones regulate specific genes on the cell’s DNA.
- membrane depolarization (Incorrect. Membrane depolarization is when the negative internal charge of the cell temporarily becomes less negative such as with an action potential.)
- inhibition of cell signaling pathways (Incorrect. Cell signaling pathways are activated and by steroid hormones that then regulate specific genes.)
- cell signaling pathways (Correct.)
A: cell signaling pathways

Q: When outside the cell, lipid-derived hormones bind to ________.
- intracellular receptors (Incorrect. The intracellular receptors reside in the cytoplasm of cells.)
- transcription regulators (Incorrect. Lipid-derived steroid hormones pass through the plasma membrane of a target cell and adhere to intracellular receptors residing in the cytoplasm or in the nucleus.)
- transport proteins (Correct. Transport proteins keep lipid-derived hormones soluble in the bloodstream.)
A: transport proteins

Q: The hormone that initiates the signaling pathway is called a ________.
- second messenger (Incorrect. The hormone that initiates the signaling pathway is called a first messenger, which activates a second messenger in the cytoplasm.)
- phosphodiesterase (Incorrect. To stop hormone activity, cAMP is deactivated by the cytoplasmic enzyme phosphodiesterase, or PDE. PDE is always present in the cell and breaks down cAMP to control hormone activity, preventing overproduction of cellular products.)
- first messenger (Correct.)
A: first messenger

Q: What is one very important second messenger in plasma membrane hormone receptor signaling?
- GTP (Incorrect. When a hormone binds to the receptor, the G-protein is activated by binding guanosine triphosphate, or GTP, in place of GDP.)
- phosphodiesterase (Incorrect. To stop hormone activity, cAMP is deactivated by the cytoplasmic enzyme phosphodiesterase, or PDE. PDE is always present in the cell and breaks down cAMP to control hormone activity, preventing overproduction of cellular products.)
- cyclic AMP (cAMP) (Correct. cAMP is a second messenger that mediates a cell-specific response.)
A: cyclic AMP (cAMP)

Q: What catalyzes the conversion of ATP to cAMP?
- protein kinases (Incorrect. Each molecule of adenylyl cyclase then triggers the formation of many molecules of cAMP. Further amplification occurs as protein kinases, once activated by cAMP, can catalyze many reactions.)
- peptide hormones (Incorrect. Peptide hormones are a class of hormones.)
- adenylyl cyclase (Correct.)
A: adenylyl cyclase

Q: The water concentration of the body is monitored by ________ in the hypothalamus.
- phosphodiesterase (Incorrect. To stop hormone activity, cAMP is deactivated by the cytoplasmic enzyme phosphodiesterase, or PDE. PDE is always present in the cell and breaks down cAMP to control hormone activity, preventing overproduction of cellular products.)
- neurotransmitters (Incorrect. Neurotransmitters are chemical messengers that enable neurotransmission.)
- osmoreceptors (Correct.)
A: osmoreceptors

Q: What produces the polypeptide hormone, antidiuretic hormone (ADH)?
- kidneys (Incorrect. ADH travels in the bloodstream to the kidneys. Once at the kidneys, ADH changes the kidneys to become more permeable to water)
- adrenal cortex (Incorrect. Another hormone responsible for maintaining electrolyte concentrations in extracellular fluids is aldosterone, a steroid hormone that is produced by the adrenal cortex.)
- hypothalamus (Correct.)
A: hypothalamus

Q: What does angiotensin II do?
- circulates in the blood and reacts with angiotensinogen (Incorrect. Renin, an enzyme, circulates in the blood and reacts with a plasma protein produced by the liver called angiotensinogen.)
- inhibits the release of the hormone aldosterone (Incorrect. Angiotensin II causes the release of aldosterone, it does not inhibit.)
- causes the release of the hormone aldosterone (Correct.)
A: causes the release of the hormone aldosterone

Q: Regulation of the reproductive system is a process that requires the action of ________ from the pituitary gland, the adrenal cortex and the gonads.
- angiotensin (Incorrect. Angiotensin is produced by the liver and causes vasoconstriction and a subsequent increase in blood pressure.)
- aldosterone (Incorrect. Aldosterone, is a steroid hormone which promotes the reabsorption of water to maintain proper water balance.)
- hormones (Correct.)
A: hormones

Q: What are gonadotropins?
- hormones that regulate the male reproductive system only (Incorrect. Gonadotropins regulate gonads (testes in males and ovaries in females).)
- hormones that regulate the female reproductive system only (Incorrect. Gonadotropins regulate gonads (testes in males and ovaries in females).)
- hormones that regulate the gonads (Correct.)
A: hormones that regulate the gonads

Q: What do estrogens do?
- stimulate the maturation of sperm cells in males (Incorrect. This is what FSH does.)
- stimulate the production of the androgen testosterone (Incorrect. This is what luteinizing hormone (LH) does.)
- trigger the development of secondary sex characteristics in females (Correct.)
A: trigger the development of secondary sex characteristics in females

Q: What are the two hormones primarily responsible for maintaining homeostasis of blood glucose?
- insulin and aldosterone (Incorrect. Aldosterone, is a steroid hormone which promotes the reabsorption of water to maintain proper water balance.)
- insulin and growth hormone (Incorrect. Growth hormone stimulates growth, cell reproduction and cell regeneration in humans.)
- insulin and glucagon (Correct.)
A: insulin and glucagon

Q: What does glycogenolysis do?
- stimulates absorption of amino acids from the blood by the liver, which then converts them to glucose (Incorrect. This is glycogenesis.)
- prevents the oversecretion of insulin (Incorrect. This is hypoglycemia.)
- stimulates the breakdown of glycogen to glucose in skeletal muscle cells and liver cells (Correct.)
A: stimulates the breakdown of glycogen to glucose in skeletal muscle cells and liver cells

Q: What two hormones determine the basal metabolic rate?
- insulin and glucagon (Incorrect. These two hormones are primarily responsible for maintaining homeostasis of blood glucose)
- glucagon and aldosterone (Incorrect. Glucagon is primarily responsible for maintaining blood glucose homeostasis and aldosterone promotes the reabsorption of water to maintain proper water balance.)
- thyroxine (T_4) and triiodothyronine (T_3) (Correct.)
A: thyroxine (T_4) and triiodothyronine (T_3)

Q: Regulation of ________is important for generation of muscle contractions and nerve impulses, which are electrically stimulated.
- glucose concentrations (Incorrect. Blood calcium not glucose are important for generation of muscle contractions.)
- cell growth (Incorrect. Blood calcium not cell growth are important for generation of muscle contractions.)
- blood calcium concentrations (Correct. If calcium levels get too high, membrane permeability to sodium decreases and membranes become less responsive. If calcium levels get too low, membrane permeability to sodium increases and convulsions or muscle spasms can result.)
A: blood calcium concentrations

Q: Blood calcium levels are regulated by ________.
- growth hormone (GH) (Incorrect. GH stimulates glycogen breakdown in the liver; the glycogen is then released into the blood as glucose.)
- insulin-like growth factors (IGFs) (Incorrect. IGFs stimulate the uptake of amino acids from the blood, allowing the formation of new proteins.)
- parathyroid hormone (PTH) (Correct. Blood calcium levels are regulated by parathyroid hormone (PTH), which is produced by the parathyroid glands.)
A: parathyroid hormone (PTH)

Q: What does calcitonin do?
- increases calcium levels by targeting the skeleton, the kidneys, and the intestine (Incorrect. This is true of PTH.)
- triggers the formation of calcitriol, an active form of vitamin D, which acts on the intestines to increase absorption of dietary calcium (Incorrect. This is true of PTH.)
- decreases blood calcium levels by inhibiting osteoclasts, stimulating osteoblasts, and stimulating calcium excretion by the kidneys (Correct.)
A: decreases blood calcium levels by inhibiting osteoclasts, stimulating osteoblasts, and stimulating calcium excretion by the kidneys

Q: What does growth hormone (GH) do?
- regulates the stress response via the hypothalamus (Incorrect. This is the sympathetic nervous system.)
- target the breakdown of fat into fatty acids in the adipose tissue (Incorrect. There are two main corticosteroids: glucocorticoids such as cortisol, and mineralocorticoids such as aldosterone. These hormones target the breakdown of fat into fatty acids in the adipose tissue.)
- accelerates the rate of protein synthesis, particularly in skeletal muscle and bones (Correct.)
A: accelerates the rate of protein synthesis, particularly in skeletal muscle and bones

Q: What do Insulin-like growth factors (IGFs) do?
- inhibit release of growth hormone. (Incorrect. This is growth hormone-inhibiting hormone (GHIH).)
- decreases blood calcium levels by inhibiting osteoclasts, stimulating osteoblasts, and stimulating calcium excretion by the kidneys. (Incorrect. This is calcitonin.)
- stimulate the uptake of amino acids from the blood allowing the formation of new proteins (Correct.)
A: stimulate the uptake of amino acids from the blood allowing the formation of new proteins

Q: The growth hormone mediated increase in blood glucose levels is called ________.
- the glucose-sparing effect (Incorrect. The first direct action of GH is stimulation of triglyceride breakdown (lipolysis) and release into the blood by adipocytes. This results in a switch by most tissues from utilizing glucose as an energy source to utilizing fatty acids. This process is called a glucose-sparing effect.)
- up-regulation (Incorrect. Up-regulation refers to an increase in the number of receptors in response to rising hormone levels.)
- the diabetogenic effect (Correct. The GH mediated increase in blood glucose levels is called a diabetogenic effect because it is similar to the high blood glucose levels seen in diabetes mellitus.)
A: the diabetogenic effect

Q: The sympathetic nervous system regulates the ________via the hypothalamus.
- levels of calcium in the bloodstream (Incorrect. This is regulated by parathyroid hormone.)
- levels of glucose in the bloodstream (Incorrect. This is regulated by insulin and glucagon.)
- stress response (Correct.)
A: stress response

Q: In a long-term stress response, the hypothalamus triggers the release of ________ from the anterior pituitary gland.
- antidiuretic hormone (ADH) (Incorrect. The principal action of ADH is to regulate the amount of water excreted by the kidneys.)
- parathyroid hormone (PTH) (Incorrect. PTH regulates blood calcium levels.)
- adrenocorticotropic hormone (ACTH) (Correct.)
A: adrenocorticotropic hormone (ACTH)

Q: Hypersecretion of glucocorticoids can cause a condition known as ________.
- Addison’s disease (Incorrect. Hyposecretion of the corticosteroids can cause Addison’s disease, which may result in bronzing of the skin, hypoglycemia, and low electrolyte levels in the blood.)
- diabetes insipidus (Incorrect. Chronic underproduction of antidiuretic hormone (ADH) or a mutation in ADH receptor results in Diabetes insipidus.)
- Cushing’s disease (Correct. Hypersecretion of glucocorticoids can cause a condition known as Cushing’s disease, characterized by a shifting of fat storage areas of the body.)
A: Cushing’s disease

Q: What does the hypothalamus do in vertebrates?
- Integrates the immune and endocrine systems. (Incorrect. The hypothalamus contains autonomic centers that control endocrine cells in the adrenal medulla via neuronal control.)
- Integrates the endocrine and excretion systems. (Incorrect. The hypothalamus contains autonomic centers that control endocrine cells in the adrenal medulla via neuronal control.)
- Integrates the endocrine and nervous systems. (Correct. The hypothalamus acts as an endocrine organ, synthesizing hormones and transporting them along axons to the posterior pituitary gland.)
A: Integrates the endocrine and nervous systems.

Q: The two regions of the pituitary secretes ________ different peptide or protein hormones.
- seven (Incorrect.)
- five (Incorrect.)
- nine (Correct.)
A: nine

Q: What is the hypophyseal portal system?
- a capillary network that extends from the hypothalamus, down along the infundibulum, and to the liver (Incorrect. It extends to the anterior pituitary)
- a nerve network that extends from the hypothalamus, down along the infundibulum, and to the anterior pituitary (Incorrect. It is a blood vessel network, not a nerve network.)
- a capillary network that extends from the hypothalamus, down along the infundibulum, and to the anterior pituitary (Correct.)
A: a capillary network that extends from the hypothalamus, down along the infundibulum, and to the anterior pituitary

Q: The thyroid gland is made up of many spherical thyroid follicles, which are lined with ________.
- columnar epithelium (Incorrect. This is found in ciliated tissues.)
- squamous epithelium (Incorrect. This is found in the lining of blood vessels.)
- cuboidal epithelium (Correct. These follicles contain the viscous fluid colloid.)
A: cuboidal epithelium

Q: What is produced by the parafollicular cells?
- thyroxine (Incorrect. This is produced thyroid follicle cells)
- triiodothyronine (Incorrect. This is produced thyroid follicle cells)
- calcitonin (Correct.)
A: calcitonin

Q: What does parathyroid hormone (PTH) do?
- decrease blood calcium (Incorrect. This is function of calcitonin.)
- increase blood sodium (Incorrect. This is function of aldosterone.)
- increase blood calcium (Correct.)
A: increase blood calcium

Q: The adrenal glands are associated with the ________.
- gastrointestinal tract (Incorrect. The thyroid and parathyroid glands make hormones that act on the intestines.)
- pancreas (Incorrect. The pancreas makes insulin and glucagon, hormones that act on the liver, muscle and adipose tissue.)
- kidneys (Correct. The adrenal glands are associated with the kidneys; one gland is located on top of each kidney)
A: kidneys

Q: The adrenal cortex is made up of ________.
- cuboidal epithelium and associated capillary networks (Incorrect. Cuboidal epithelium lines the thyroid follicles of the thyroid gland.)
- parafollicular cells and associated capillary networks (Incorrect. Parafollicular cells are found in the thyroid gland.)
- layers of epithelial cells and associated capillary networks (Correct.)
A: layers of epithelial cells and associated capillary networks

Q: The adrenal medulla contains two types of secretory cells that produce ________.
- insulin and glucagon (Incorrect. The pancreas produces these two hormones.)
- follicle stimulating hormone and luteinizing hormone. (Incorrect. The pituitary produces these two hormone)
- epinephrine and norepinephrine (Correct. The adrenal medulla contains two types of secretory cells: one that produces epinephrine (adrenaline) and another that produces norepinephrine (noradrenaline).)
A: epinephrine and norepinephrine

Q: What are two hormones that the pancreas produces?
- thyroxine and triiodothyronine (Incorrect. These are produced by the thyroid.)
- epinephrine and norepinephrine (Incorrect. These are produced by the adrenal medulla.)
- insulin and glucagon (Correct. The pancreatic islets contain two primary cell types: alpha cells, which produce the hormone glucagon, and beta cells, which produce the hormone insulin.)
A: insulin and glucagon

Q: What does the pineal gland produce?
- glucagon (Incorrect. Glucagon is produced by the pancreas.)
- aldosterone (Incorrect. Aldosterone is produced by the parathyroid.)
- melatonin (Correct.)
A: melatonin

Q: The ________ produce the steroid hormones, androgen and progesterone.
- pineal gland (Incorrect. The pineal gland produces melatonin.)
- hypothalamus (Incorrect. The hypothalamus produces releasing and inhibiting hormones.)
- gonads (Correct.)
A: gonads

Q: The endocrine cells in the walls of the heart atria produce________.
- oxytocin (Incorrect. Oxytocin is produced by the pituitary.)
- Thyroid stimulating hormone (TSH) (Incorrect. TSH is produced by the pituitary)
- atrial natriuretic peptide (ANP) (Correct. The heart possesses endocrine cells in the walls of the atria that are specialized cardiac muscle cells. These cells release the hormone atrial natriuretic peptide (ANP) in response to increased blood volume.)
A: atrial natriuretic peptide (ANP)

Q: What type of hormones does the thymus produce?
- growth hormone (Incorrect. Growth hormone is produced by the pituitary gland.)
- aldosterone (Incorrect. Aldosterone is produced by the parathyroid.)
- thymosins (Correct. The thymus produces hormones referred to as thymosins, which contribute to the development of the immune response.)
A: thymosins

Q: What does the protein hormone erythropoietin do?
- increases the activity of anorexigenic neurons and decreases that of orexigenic neurons (Incorrect. This is the function of leptins.)
- acts on the kidneys to reduce the reabsorption of sodium (Incorrect. This is the function of ANP.)
- triggers the formation of red blood cells in the bone marrow (Correct.)
A: triggers the formation of red blood cells in the bone marrow