Chapter 17 – The Endocrine System (Vocabulary Review)

Vocabulary flashcards covering key endocrine terms, hormones, glands, and regulatory concepts from Chapter 17.

Which body system is a system of hormone-secreting glands and cells that regulates body activities and maintains homeostasis via chemical messengers carried in the blood?

Endocrine System

What is a chemical messenger released in one part of the body that regulates the activity of cells in another part?

Hormone

Which type of gland releases secretions into ducts leading to body surfaces or cavities (e.g., sweat, salivary)?

Exocrine Gland

What is a ductless gland that releases hormones into interstitial fluid, then blood, to reach target tissues?

Endocrine Gland

What chemical is released by neurons to transmit signals across a synapse and mediates nervous system control?

Neurotransmitter

What is a cell that bears specific receptors and is affected by a particular hormone?

Target Cell

What is the protein on or within a target cell that binds a specific hormone and initiates a response?

Hormone Receptor

What is the term for a decrease in the number of hormone receptors when hormone levels are high, reducing sensitivity?

Down-regulation

What is the term for an increase in the number of hormone receptors when hormone levels are low, raising sensitivity?

Up-regulation

Which type of hormone (e.g., steroid, thyroid) diffuses through the plasma membrane and binds intracellular receptors?

Lipid-Soluble Hormone

Which type of hormone (e.g., peptide, amine) binds membrane receptors and uses second messengers inside the cell?

Water-Soluble Hormone

What is the liver-made plasma protein that carries lipid-soluble hormones, increasing their blood solubility and reserve?

Transport Protein

What occurs when one hormone requires a second hormone to be present to exert its full effect?

Permissive Effect

What is the term for two hormones acting together to produce a greater effect than either alone?

Synergistic Effect

What is the term for one hormone opposing the action of another hormone?

Antagonistic Effect

Which brain region is located below the thalamus, serves as a major link between the nervous and endocrine systems, and controls the pituitary?

Hypothalamus

What is the stalk connecting the hypothalamus to the pituitary gland?

Infundibulum

Which endocrine gland, located in the sella turcica, consists of anterior (glandular) and posterior (neural) lobes?

Pituitary Gland (Hypophysis)

Which glandular lobe of the pituitary produces hGH, TSH, ACTH, FSH, LH, PRL, and MSH?

Anterior Pituitary (Adenohypophysis)

Which neural lobe of the pituitary stores and releases hypothalamic hormones like oxytocin and ADH?

Posterior Pituitary (Neurohypophysis)

What is a hormone that stimulates another endocrine gland to secrete its hormones?

Tropic Hormone (Tropin)

What is the two-capillary network that carries hypothalamic releasing/inhibiting hormones to the anterior pituitary?

Hypophyseal Portal System

Which anterior pituitary hormone stimulates the adrenal cortex to secrete glucocorticoids (e.g., cortisol)?

Adrenocorticotropic Hormone (ACTH)

Which anterior pituitary hormone stimulates IGF production for tissue growth, lipolysis, and glucose elevation?

Human Growth Hormone (hGH)

Which anterior pituitary hormone triggers thyroid secretion of T3 and T4?

Thyroid-Stimulating Hormone (TSH)

Which gonadotropic hormone initiates follicle development in females and stimulates sperm production in males?

Follicle-Stimulating Hormone (FSH)

Which gonadotropic hormone triggers ovulation and progesterone/estrogen secretion in females, and stimulates testosterone in males?

Luteinizing Hormone (LH)

Which anterior pituitary hormone initiates milk production in mammary glands?

Prolactin (PRL)

Which anterior pituitary peptide's human role is unclear, but its excess can darken skin and may affect brain activity?

Melanocyte-Stimulating Hormone (MSH)

Which posterior pituitary hormone enhances uterine contractions and stimulates milk ejection?

Oxytocin (OT)

Which posterior pituitary hormone conserves body water, reduces urine output, and raises blood pressure?

Antidiuretic Hormone (ADH, Vasopressin)

Which butterfly-shaped gland, located inferior to the larynx, has follicles that produce T3/T4 and parafollicular cells that secrete calcitonin?

Thyroid Gland

Which thyroid hormone contains three iodine atoms and increases metabolic rate and development?

Triiodothyronine (T_3)

Which thyroid hormone contains four iodine atoms and is a precursor converted to T_3 in tissues?

Thyroxine (T_4)

What plasma protein transports T3 and T4 in the bloodstream?

Thyroxine-Binding Globulin (TBG)

Which thyroid parafollicular hormone lowers blood calcium and phosphate by inhibiting osteoclasts?

Calcitonin (CT)

Which glands are four small glands located on the posterior thyroid that secrete parathyroid hormone?

Parathyroid Gland

Which chief-cell hormone raises blood calcium, stimulates osteoclasts, and promotes calcitriol formation?

Parathyroid Hormone (PTH)

Which outer region of the adrenal gland produces mineralocorticoids, glucocorticoids, and androgens?

Adrenal Cortex

Which adrenal cortical steroid hormones regulate mineral homeostasis, with aldosterone as their main member?

Mineralocorticoids

Which mineralocorticoid increases renal Na^+ and water reabsorption, K^+ excretion, and regulates blood pressure?

Aldosterone

Which adrenal cortical hormones (e.g., cortisol) influence metabolism and stress resistance?

Glucocorticoids

Which major glucocorticoid increases gluconeogenesis, protein breakdown, lipolysis, and suppresses inflammation?

Cortisol

Which weak male sex steroids from the inner adrenal cortex contribute to female libido and pubic/axillary hair?

Androgens (Adrenal)

Which inner adrenal region is a modified sympathetic ganglion secreting epinephrine and norepinephrine?

Adrenal Medulla

Which catecholamine intensifies fight-or-flight responses by increasing heart rate, airway dilation, and blood glucose?

Epinephrine (Adrenaline)

Which catecholamine works with epinephrine to augment sympathetic responses to stress?

Norepinephrine (Noradrenaline)

What are the clusters of endocrine cells in the pancreas containing alpha (glucagon) and beta (insulin) cells?

Pancreatic Islets (Islets of Langerhans)

Which alpha-cell hormone raises blood glucose by stimulating glycogen breakdown and gluconeogenesis in the liver?

Glucagon

Which beta-cell hormone lowers blood glucose by promoting cellular uptake and storage as glycogen, fat, and protein?

Insulin

Which female gonad produces estrogens, progesterone, relaxin, and inhibin?

Ovary

Which female steroid hormone regulates the reproductive cycle and promotes secondary sex characteristics?

Estrogen

Which ovarian hormone prepares the uterus for implantation and maintains pregnancy with estrogen?

Progesterone

Which male gonad produces testosterone and inhibin?

Testis

Which principal male androgen regulates sperm production and secondary sex characteristics?

Testosterone

Which ovarian (and placental) hormone increases pubic symphysis flexibility and dilates the cervix during labor?

Relaxin

Which gonadal peptide inhibits FSH secretion from the anterior pituitary?

Inhibin

Which small gland on the roof of the third ventricle secretes melatonin to regulate biological rhythms?

Pineal Gland

Which pineal hormone's level rises during darkness, contributing to sleep-wake cycle regulation?

Melatonin

Which stomach hormone promotes gastric juice secretion and stomach motility?

Gastrin

Which duodenal hormone stimulates pancreatic bicarbonate juice and bile secretion?

Secretin

Which intestinal hormone triggers pancreatic enzyme juice, bile release, and a feeling of satiety?

Cholecystokinin (CCK)

Which intestinal hormone enhances insulin release after carbohydrate-rich meals?

Glucose-Dependent Insulinotropic Peptide (GIP)

Which kidney enzyme-hormone initiates the renin-angiotensin-aldosterone pathway to raise blood pressure?

Renin

Which kidney hormone increases the rate of red blood cell formation in bone marrow?

Erythropoietin (EPO)

What is the active form of vitamin D (kidney-formed) that increases absorption of dietary calcium and phosphate?

Calcitriol

Which heart hormone lowers blood pressure by promoting sodium and water excretion?

Atrial Natriuretic Peptide (ANP)

Which adipose-derived hormone suppresses appetite and may enhance FSH/LH activity?

Leptin