Endocrine System Flashcards

Flashcards covering vocabulary terms related to the endocrine system.

Homeostasis

A process that allows a constant internal environment to be maintained despite changes in the external environment.

Monitor

Detects the problem in the internal environment to maintain homeostasis.

Control

Fixes the problem in the internal environment to maintain homeostasis.

Pancreas

Detects high blood sugar and secretes insulin.

Insulin

Stimulates the liver to store glucose and increases cellular permeability to decrease blood sugar levels.

Endocrine System

Glands and hormones that work together with the nervous system to regulate body activities and maintain homeostasis.

Nervous System

Brain, spinal cord, and neurons that work together with the endocrine system to regulate body activities and maintain homeostasis.

Hypothalamus

Connects the endocrine system with the nervous system and tells the pituitary gland to start or stop making hormones.

Pituitary Gland

Releases hormones that affect other glands; controlled by the hypothalamus.

Hormones

Chemicals produced that control metabolic reactions; maintained at certain levels in the body.

Tropic Hormones

Hormones that target endocrine glands and cause secretion of their hormones.

Negative Feedback Loop

Prevents chemical imbalances in the body; hormone production decreases once the desired effect is produced.

ACTH RF (adrenocorticotropin releasing factor)

Releasing factor that goes to the pituitary gland

GnRH (gonadotropin releasing hormone)

Releasing hormone that goes to the pituitary gland

Oxytocin

Produced in the hypothalamus and stored in the posterior pituitary

ADH

Produced in the hypothalamus and stored in the posterior pituitary

Human Growth Hormone (hGH)

Targets most cells (bones and muscles), promotes growth (proteins).

Hyposecretion

Too low hGH

Hypersecretion

Too high hGH

Hypersecretion of ADH

Abnormal water retention due to too much ADH

Hyposecretion of ADH

Urinate more often, dehydration, low blood pressure due to too little ADH

Thyroid Stimulating Hormone (TSH)

Stimulates the thyroid gland to produce thyroxine.

Adrenocorticotropic Hormone (ACTH)

Targets the adrenal cortex and stimulates the release of stress hormones aldosterone and cortisol.

Follicle Stimulating Hormone (FSH)

Targets the ovaries and testes; Hyposecretion inhibits sexual development, causes sterility; Stimulates production of eggs and estrogen in ovaries; Stimulates sperm production in testes.

Luteinizing Hormone (LH)

Targets the ovaries and testes; Stimulates ovulation (release of egg) and progesterone and estrogen production in females; Stimulates testosterone production in males.

Lactation

Production of breast milk; stimulated by prolactin.

Thyroid Gland

Located at the base of the neck in front of the trachea; produces thyroxine and calcitonin.

Thyroxine

Targets body cells and increases rate of metabolism.

Hyperthyroidism

High metabolic rate, can’t sit still, always warm, and weight loss.

Hypothyroidism

Low metabolic rate, less energy, intolerant of cold, dry skin and weight gain.

Goitre

A swelling in the neck resulting from an enlarged thyroid gland, often caused by iodine deficiency.

Calcitonin

Hormone that lowers calcium levels in blood.

Parathyroid Hormone (PTH)

Hormone that raises calcium levels in blood.

Function of Calcitonin

Decreases blood calcium by depositing calcium in bones

Function of Parathyroid Hormone (PTH)

Increases blood calcium by removing calcium from bones

Adrenal Glands

On top of each kidney; consists of the adrenal cortex and adrenal medulla.

Adrenal Cortex

Outside of the adrenal gland, stimulated by ACTH

Adrenal Medulla

Middle of the adrenal gland, regulated by the sympathetic nervous system.

Adrenal Medulla

Activated by the sympathetic nervous system to produce epinephrine (adrenaline) during stress (fight-or-flight response).

Epinephrine (Adrenaline)

Increases blood glucose by causing the liver to convert glycogen to glucose, increases heart rate, blood pressure, and breathing rate.

Cortisol

Increases levels of amino acids in blood to help body recover from stress; liver converts amino acids into glucose.

ADH

Released from the anterior pituitary in response to dehydration.

Aldosterone

Released from the adrenal cortex in response to low blood pressure.

Aldosterone

Increases sodium reabsorption into blood from kidney, water follows by osmosis, increases blood pressure; results in lower volume & more concentrated urine.

Insulin and Glucagon

Produced by the Islets of Langerhans cells in the pancreas.

Insulin

Released after a meal to lower glucose levels in the blood by increasing all cells’ permeability to glucose and converting glucose to glycogen in liver and muscle cells.

Glucagon

Released after fasting to raise glucose levels in the blood by converting glycogen to glucose in the liver and releasing it into the blood.

Glucagon

Glucose is gone

Glucose

Sugar

Glycogen

Storage form of glucose

Diabetes Mellitus

No insulin or insulin resistant, resulting in high blood sugar levels after eating (hyperglycemia).

Diabetes Mellitus Type 1

Autoimmune disease that destroys islet cells; treatment includes insulin injections.

Diabetes Mellitus Type 2

Due to decreased insulin production or resistance to insulin; treatment includes exercise, weight loss, eating well, oral drugs, and insulin.

Islet Transplants

Islets from donor

Estrogen

Produced in ovary, promotes development of secondary (2o) sexual characteristics (breasts, body hair); Initiates thickening of uterine lining in preparation for pregnancy each month

Progesterone

Produced in ovary, targets mammary glands for development, growth and maintenance of endometrium; inhibits ovulation and prevents uterine contractions

Testosterone

Produced in interstitial cells of the testes, production is regulated by LH from the anterior pituitary, targets the Sertoli cells inside the seminiferous tubules in the testes