Endocrine System Lab

Hormones

Chemical signaling molecules that travel through the bloodstream and bind to receptors on cells to cause effects.

Target organs

Organs or tissues that respond to a specific hormone.

Endocrine glands

Ductless glands that release hormones directly into the bloodstream.

Exocrine glands

Glands that have ducts and release products into specific locations like digestive enzymes.

Hyposecretion

Hormone production that is too low or too slow.

Hypersecretion

Hormone production that is too high or excessive.

Tropic hormones

Hormones that stimulate other endocrine glands to release hormones.

Pituitary gland

Also called the hypophysis and known as the master gland because it controls other endocrine glands.

Location of pituitary gland

Sella turcica of the sphenoid bone.

Two parts of the pituitary gland

Anterior pituitary and posterior pituitary.

Growth hormone (GH)

Determines body size and controls muscle and bone growth.

Thyroid stimulating hormone (TSH)

Stimulates the thyroid gland to release thyroid hormones.

Adrenocorticotropic hormone (ACTH)

Regulates the adrenal cortex.

Follicle stimulating hormone (FSH)

Controls sperm production in males and egg production in females.

Luteinizing hormone (LH)

Stimulates testosterone production in males and estrogen production in females.

Prolactin (PRL)

Stimulates breast development and maintains milk production.

Posterior pituitary function

Stores and releases hormones made elsewhere.

Oxytocin

Stimulates uterine contractions during childbirth.

Antidiuretic hormone (ADH)

Increases water reabsorption in the kidneys.

Thyroid gland structure

Two lobes connected by an isthmus.

Location of thyroid gland

Below the larynx in the throat.

Thyroid hormone (TH)

Controls the rate of metabolism in most cells.

T4 (thyroxine)

One of the main thyroid hormones regulating metabolism.

T3 (triiodothyronine)

More active thyroid hormone regulating metabolism.

Calcitonin

Lowers blood calcium levels by causing calcium to deposit in bones.

Parathyroid glands

Small glands embedded in the back of the thyroid gland.

Parathyroid hormone (PTH)

Main regulator of blood calcium levels.

Effect of PTH when calcium is low

Releases calcium from bones and increases kidney reabsorption of calcium.

Thymus gland location

Upper chest behind the sternum and in front of the heart.

Thymus gland function

Helps white blood cells mature and specialize.

Thymus hormones

Thymosin and thymopoietin.

Adrenal glands location

On top of each kidney.

Two regions of adrenal glands

Adrenal cortex and adrenal medulla.

Adrenal cortex

Produces steroid hormones called corticosteroids.

Mineralocorticoids

Regulate water and electrolyte balance such as aldosterone.

Glucocorticoids

Increase blood glucose levels such as cortisone.

Gonadocorticoids

Sex hormones such as androgens and estrogens.

Adrenal medulla

Controlled by the sympathetic nervous system.

Epinephrine

Hormone involved in the fight or flight response.

Norepinephrine

Hormone that increases heart rate and blood pressure during stress.

Pancreas location

In the abdomen behind the stomach.

Pancreas exocrine function

Acinar cells produce digestive enzymes released into ducts.

Pancreas endocrine function

Alpha and beta cells produce hormones.

Insulin

Lowers blood glucose and helps glucose enter cells.

Glucagon

Raises blood glucose by stimulating glycogen breakdown.

Ovaries location

In the pelvic cavity.

Estrogen

Causes female secondary sex characteristics.

Progesterone

Regulates the menstrual cycle and maintains pregnancy.

Testes location

In the scrotum outside the pelvic cavity.

Testosterone

Causes male secondary sex characteristics.

Pineal gland location

In the third ventricle of the brain.

Melatonin

Controls circadian rhythms and sleep wake cycles.

Acromegaly

Excess growth hormone in adults causing enlarged face hands and feet.

Addison's disease

Too little cortisone causing low blood pressure.

Cushing's disease

Too much cortisone causing high blood glucose.

Diabetes insipidus

Too little ADH causing excessive urination and dehydration.

Diabetes mellitus

Too little insulin causing inability to properly use glucose.

Dwarfism

Too little growth hormone in children.

Gigantism

Too much growth hormone before growth plates close.

Graves' disease

Too much thyroid hormone causing high metabolism nervousness weight loss sweating and irregular heartbeat.

Hypersecretion of PTH

Causes calcium to leave bones making them weak or deformed.

Hypoglycemia

Too much insulin causing low blood sugar.

Myxedema

Too little thyroid hormone causing mental and physical sluggishness.

Tetany

Too little PTH causing muscle spasms and increased nerve excitability from low calcium.