14-The Endocrine System Flashcards
What germ layers do endocrine glands develop from?
all germ layers
What are characteristics of endocrine glands?
Ductless, secrete directly into the blood stream
What are tropic hormones?
Hormones that affect the release of other hormones e.g. gonadotropins, hormones like LH and FSH that stimulate release of sex hormons from the gonads.
What are the three types of hormones?
Peptides (most common), Steroids (lipids derived from cholesterol) and Biogenic amines (produced by altering amino acids) e.g. thyroid hormone
What are the two hormones produced by the hypothalamus and where are they stored?
Oxytocin and antidiuretic hormone. Both stored in the Posterior Pituitary gland
What is the third endocrine function of the hypothalamus?
Creates and releases hormones that control the excretion of hormones from the anterior pituitary.
What is the other name for the anterior pituitary gland? What is made of?
adenohypophysis. Glandular tissue
What is the hpophyseal portal system?
Portal veins that route blood from the hypothalamus to the pituitary before going to heart so as to carry regulatory signals there quickly.
What is the other name of the posterior pituitary gland?
neurohypophysis.
What are the hormones of the posterior pituitary, of neurohypophysis and where are they made?
Antidiuretic hormone or vasopressin, and oxytocin. They are made in the hypothalamus.
What is vasopressin and what does it do?
Hormone which initiates water reabsorptioin, increases blood pressure through vasoconstriction.
What does hypersecretion of vasopressin cause?
edema
What does hyposecretion of vasopressin (antidiuretic hormone) cause?
Diabetes insipidus
What does oxytocin do?
Causes smooth muscle contraction in reproductive organs, uterine contractions and milk ejection
What are the hormones produced and released by adenohypophysis (anterior pituitary?)
Follicle Stimulating Hormone (FSH) Luteinizing Hormone (LH) Adrenocorticotropic hormone (ACTH) Prolactin (PRL) Growth Hormone (GH) Melanocyte Stimulating Hormone (MSH)
What hormones are released from posterior pituitary gland?
Oxytocin, antidiuretic hormone
What is the target organ of oxytocin and what does it induce?
Reproductive organs. Causes smooth muscle contraction
What is the target organ of ADH (vasopressin or antidiuretic hormone)? What is its function?
Kidneys. Water retention.
What is the target organ of FSH (Follicle Stimulating Hormone)?
Gonads
What is the target organ of LH (Luteinizing Hormone)?
Gonads
What is the target organ of ACTH (adrenocorticotropic hormone)?
Adrenal Cortex
What is the target organ of TSH (thyroid stimulating hormone)?
Thyroid
What is the target organ of Prolactin?
Mammary glands to stimulate milk production
What is the target organ of GH?
Skeletal muscle, fat, bone, etc. Makes you grow and can cause gigantism, acromegaly, etc…
What is the target organ of MSH (Melanocyte stimulating hormone)?
Melanocytes of the epidermis
What hormone is released by pineal gland and what is its function?
Melatonin. Its function is to control circadian rhythms.
What are three GH disorders, what are their symptoms and what is their cause?
Pituitary Dwarfism, extreme shortness, caused by hyposecretion of GH in children
Pituitary Gigantism, extreme height, hypersecretion of GH during childhood
Acromegaly, causes thickening of bones, hypersecretion of GH during adulthood.
What is the largest pure endocrine gland?
Thyroid gland
What hormones are produced by the thyroid?
T3 and T4, or thyroid hormone, and calcitonin
What does thyroid hormone do?
Increases metabolic rate
What does calcitonin do?
Lowers levels of blood calcium. Increases osteoblast activity and decreases osteoclast activity.
What causes and endemic goiter?
Dietary iodine deficiency
What causes hperthroidism, what is its other name, and symptoms?
Excessive TH production. Called Grave’s Disease. Causes tachycardia, exophthalmos
What is hypothroidism and what are its symptoms?
Caused by decreased production of TH. Symptoms are fatigue, weakness, dry skin, weight gain, reduced libido.
Where are the parathyroid glands located?
Posterior surface of thyroid
What hormone does the parathyroid producee?
Parathyroid hormone
What does parathyroid hormone do?
Acts as opposite of calcitonin. Increase blood Ca levels, increases osteoclast activity, decreases osteoblast activity.
Where is the Thymus and what happens to it as you age?
Thymus is in lower neck and mediastinum. Yellows and atrophies after puberty.
What hormones are produced in the Thymus?
Thymopoietin and Thymosins
What do thymopoietin and Thymosin do?
These hormones stimulate differentiation, growth, and maturation of t-lymphocityes.
What are the two layers of the adrenal/suprarenal glands?
Adrenal cortex and adrenal medulla
What hormones are produced in adrenal cortex?
Aldosterone and cortisol
What does aldosterone do?
Deals with water retention
What does cortisol do?
Helps the body deal with stressful situations by supressing normal protective responses.
What hormones are produced in Adrenal Medulla?
Epinephrine and norepinephrine?
What do epinephrine (adrenaline) and norepinephrine do?
Enhance function of sympathetic nervous system, enhancing fight or flight response.
What are corticosteroids?
Steroid hormones from adrenal cortex
What is the function of corticosteroids? What is the result of excessive use?
Inhibit the immune response by blocking inflammation and white blood cell response. Use causes increased susceptibility to infection.
What diseases are corticosteroids used to treat?
Lupus, rheumatoid arthritis, or inflammatory bowel disease
What is cushings Syndrome? What are its symptoms?
Hypersecretion of cortisol. Results in redistributed body obesity (moon face and buffalo hump), kidney stones, fragile and thin skin
What is Addison’s disease? What are its symptoms?
Hyposecretion of cortisol. Symptoms = weightloss, fatigue, skin darkening, and hypotension
What hormones are produced in the pancreatic islets?
Glucagon (which increases blood sugar by inducing glycogen breakdown in liver) and Insulin (which lowers blood sugar by causing cellular uptake of blood glucose)
What cells produce glucagon?
Alpha cells in pancreatic islets
What cells produce insulin?
Beta cells in pancreatic islets
What does T3 and T4 do?
Increases metabolism. Produced in thyroid.
What is the target organ of calcitonin and what does it do?
Bones, decreases blood Ca levels
What is the target organ of PTH (parathyroid hormone)?
Bones, increases blood Ca level
What is the target organ of thymopoietin and thymosin and what does it do?
Thymus, stimulates T-cell maturation.
What is the target organ of Aldosterone, where is it produced, and what does it do?
Produced in adrenal cortex, target organ is kidney. Causes water retention
What is the function of cortisol?
Responds to stress
What hormones are produced in Adrenal medulla and what do they do?
Epiniphrine and norepinephrine, increase sympathetic response.
