Human Anatomy & Physiology: Chapter 16 The Endocrine System Flashcards

chemical messengers secreted by cells into the extracellular fluids

• Reproduction
• Growth and development
• Maintenance of electrolyte, water, and nutrient balance of the blood
• Regulation of cellular metabolism and energy balance
• Mobilization of bode defenses

Endocrinology

produce hormones and lack ducts

• Pituitary
• Thyroid
• Parathyroid
• Adrenal
• Pineal
• Pancreas
• Gonads (Ovaries and testes)
• Placenta
• Hypothalamus

chemicals that exert their effects on the same cells that secret them

affect cell types other than those releasing the paracrine chemicals

either amino acid based or steroids

the activity of only those tissue cells that have receptors for it

are tissues with receptors for specific hormone

• alters plasma membrane permeability or membrane potential, or both, by opening or closing ion channels
• stimulates synthesis of enzymes and other proteins withing the cell
• activates or deactivates enzymes
• induces secretory activity
• stimulates mitosis

act on receptors in the plasma membrane

act on receptors inside the cell

exert their signaling effects through intracellular second messenger generated when a hormone binds to a receptor in the plasma membrane

• a hormone receptor
• a G protein
• and an effector enzyme (adenylate cylase)

• blood levels of the hormone
• relative numbers of receptors for that hormone on or in the target cells
• strength of the binding between the hormone and the receptor

are target cells that form more receptors in response to low hormone levels

are target cells that lose receptors in response to high hormone levels

• Humoral
• Neural
• Hormonal Stimuli

secrete their hormones in direct response to changing blood levels of certain critical ions and nutrients

happens when nerve fibers stimulate hormone release

release their hormones in response to hormones produced by other endocrine organs

• Free
• Bound to a protein carrier

• its rate of release
• the speed at which it is inactivated and removed from the body

is the situation in which one hormone cannot exert its full effects without another hormone being present

occurs when more than one hormone produces the same effects at the target cell and their combined effects are amplified

occurs when one hormone opposes the action of another hormone

also called the hypophysis, secretes at least eight hormones

is composed largely of neural tissue.

is a hormone storage area and not a true endocrine gland that manufactures hormones

is commonly called neurohypophysis

is commonly called adenohypophysis

is composed of glandular tissue

• Oxytocin
• Antidiuretic Hormone (ADH)

is released in significantly higher amounts during childbirth and in nursing women

prevents wide swings in water balance, helping the body avoid dehydration and water overload

• Growth hormone (GH)
• Thyroid-stimulating hormone (TSH)
• Adrenocorticotropic hormone (ACTH)
• Follicle-stimulating hormone (FSH)
• Luteinizing hormone (LH)
• Prolactin (PRL)

regulate the secretory action of other endocrine glands

• Thyroid-stimulating hormone (TSH)
• Adrenocorticotropic hormone (ACTH)
• Follicle-stimulating hormone (FSH)
• Luteinizing hormone (LH)

located in the anterior neck, on the trachea just inferior to the larynx

is a median tissue mass that connects its two lateral lobes

Thyroid hormone (TH)

is two iodine-containing amine hormones, thyroxine, or T₄, and triiodothyronine, or T₃

• Increasing basal metabolic rate and body heat production, by turning on transcription of genes concerned with glucose oxidation
• Regulating tissue growth and development
• Maintaining blood pressure by increasing the number of adrenergic receptors in blood vessels

composed of hollow, spherical follicles

produce the glycoprotein thyroglobulin

stores colloid

thyroxine - binding globulins (TBGs)

a polypeptide hormone released by the parafollicular, or C, cells of the thyroid gland in response to a rise in blood Ca²⁺ levels

are tiny, yellow-brown glands nearly hidden from view in the posterior aspect of the thyroid gland

is the single most important hormone controlling calcium balance in the blood

are pyramid-shaped organs perched atop the kidneys, where they are enclosed in a fibrous capsule and a cushion of fat

Suprarenal glands

is part of the sympathetic nervous system

is glandular tissue derived from embryonic mesoderm

• Zona glomerulosa
• Zona fasciculata
• Zona reticularis

produces mineralocorticoids, hormones that help control the balance of minerals and water in the blood

mainly produce the metabolic hormones called glucocorticoids

mainly produce small amounts of adrenal sex hormones, or gonadocorticoids

produce growth hormone (GH)

increases blood levels of fatty acids, encourages use of fatty acids for fuel, and protein synthesis

medieates most of its growth- enhancing effects indirectly vie a family of growth-promoting proteins called insulin-like growth factors (IGFs)

stimulates GH release

inhibits GH release

somatostatin

is a tropic hormone that stimulates normal development and secretory activty of the thyroid gland

is secreted by the corticotropic cells of the anterior pituitary

Thyrotropin

Corticotropin

Follicle-stimulating hormone (FSH) and Luteinizing hormone (LH)

regulate the function of the gonads (ovaries and testes)

is a protein hormone structurally similar to GH

stimulate milk production by the breasts

essential function is to regulate the electrolyte (mineral salts) concentrations in extracellular fluids, particularly of Na⁺ and K⁺

changes in blood volume and blood pressure

reduces excretion of Na⁺ from the body, thereby lowering blood volume and blood pressure

influences both blood volume and blood pressure by regulating the release of aldosterone and therefore Na⁺ and water reabsorption by the kidneys

influence the energy metabolism of most body cells and help is resist stressors

• Cortisol (hydrocortisone)
• Cortisone
• Corticosterone

• Depress cartilage and bone formation
• Inhibit inflammation by decreasing the release of inflammatory chemicals
• Depress the immune system
• Disrupt normal cardiovascular, neural, and gastrointestinal function

secreted by the adrenal cortex are weak, androgens, or male sex hormones.

catecholoamines (epinephrine and norepinephrine)

hangs from the roof of the third ventricle in the diencephalon

pinealocytes

melatonin

an amine hormone derived from serotonin

is a mixed gland composed of both endocrine and exocrine gland cells

produce an enzyme-rich juice that is carried by ducts to the small intestine during digestion

tiny cell clusters that produce pancreatic hormones

• the glucagon-synthesizing Alpha cells
• insulin-synthesizing Beta cells

is a hyperglycemic hormones

is a hypoglycemic hormone

is a 29-amino-acid polypeptide

• Breakdown of glycogen to glucose
• Synthesis of glucose from lactic acid and from noncarbohydrate molecules
• Release of glucose to the blood by liver cells, causing blood glucose levels to rise

is a small protein consisting of two amino acid chains linked by disulfide bonds

is a large polypeptide chain that synthesizes insulin

• Enhances membrane transport of glucose into most body cells
• Inhibits the breakdown of glycogen to glucose
• Inhibits the conversion of amino acids or fats to glucose

Glucagon stimulates glycogen breakdown

produce steriod sex hormones

located in the female's abdominopelvic cavity

ova, or eggs, and estrogens ad progesterone

located in an extra-abdominal skin pouch called the scrotum

produce sperm and male sex hormones, primarily testosterone

temporary endocrine organ

estrogen and progesterone and human chorionic gonadotropin (hCG)

released by Adipose cells, tells your body how much stored energy you have

Adiponectin enhances sensitivity to insulin

hormone-secreting cells sprinkled in the mucosa of the gastrointestinal (GI) tract

secreted by specialized cardiac (heart) muscle cells

decreases the amount of sodium in the extracellular fluid

a glycoprotein hormone that signals the bone marrow to increase production of Red Blood Cells (RBCs)

a hormone that prods pancreatic beta cells to divide and secrete more insulin

an inactive form of vitamin D₃

the active form of vitamin D₃

• Heart
• Gastrointestinal Tract
• Kidneys
• Skin
• Adipose Tissue
• Skeleton
• Thymus

• Thymulin
• Thymopoietins
• Thymosins