Endocrine System Flashcards
What are the glands of the endocrine system?
- Hypothalamus
- Pituitary (Posterior & Anterior)
- Pineal Gland
- Pancreas
- Thyroid
- Parathyroid
- Adrenal Glands
What are endocrine secretions?
Endo secretes hormones into the bloodstream
What are exocrine secretions?
Exocrine secretes to outside of body. Includes secretions into hollow organs. I.e. digestive enzymes, saliva, sweat, tears, mucus, bile
What are Paracrine secretions?
These secretions act locally. Like immune related hormones or inflammatory reactions.
What three endocrine system glands are located in the brain?
- Hypothalamus
- Posterior and Anterior Pituitary
- Pineal gland
What does the hypothalamus do?
It is part nervous system and part endocrine system.
Nervous system - It regulates thirst, hunger, body temp etc
Endocrine system - it is the master gland of the endocrine system. Creates releasing and inhibiting hormones.
What does the posterior pituitary do?
Stores hormones and releases them into the bloodstream.
It stores (ADH) Antidiuretic hormone and oxytocin.
What gland makes ADH and Oxytocin?
Hypothalamus
What does ADH (Anti-Diuretic Hormone) do?
Increases reabsorption of H20 in collecting ducts of the nephron (kidneys).
ADH is released when body fluids become too concentrated.
What does oxytocin do?
- Promotes delivery of fetus by causing uterine contractions
- Ejection of breast milk
- Cuddling hormone
What hormones does the anterior pituitary make?
FLATPG
- Follicle Stimulating Hormone
- Luteinizing hormone
- Adrenocorticotropic (ACTH) hormone
- Thyroid stimulating hormone
- Prolactin hormone
- Growth hormone
What does follicle stimulating hormone do?
FSH promotes making/maturation of sperm in the testes and oocytes in the ovaries
What does luteinizing hormone do?
Surges on day 14 of the female reproductive cycle to trigger ovulation
What does ACTH/Adrenocorticotropic hormone do?
It tells the adrenal cortex to make cortisol
What does Thyroid Stimulating hormone do?
It tells the thyroid to make thyroid hormone (T3 and T4)
What does Prolactin do?
It promotes locttion/making of breast milk
What does Growth hormone do?
Growth hormone is converted to insulin-like growth factor 1 by liver and then many tissues respond to that.
What gland does adrenocorticotropic hormone stimulate?
The adrenal cortex
What is the Pineal gland located?
Pineal gland is located in the diencephalon of the brain
What hormone does the pineal gland create?
It creates Melatonin
Where is the pancreas located?
The pancreas is located posterior to the stomach. The head of the pancreas nestled in curvature of duodenum and tail goes towards the spleen
What hormones does the pancreas make?
- Insulin
- Glucagon
What does Insulin do?
- Lowers blood sugar (after eating) by promoting cellular utilization of glucose
- Promotes glycogenesis - making of glycogen in liver and muscles
- Promotes adipose tissue to convert glucose to fat (lipogenesis
What is Glycogen?
Glycogen is stored glucose. It is stored in the liver and muscles.
What does glucagon do?
- Raises blood sugar during starvation situation
- Promotes glycogenolysis - breakdown of glycogen
- Promotes lipolysis - breakdown of fat
- Promotes gluconeogenesis - the creation of new glucose from non-glucose sources (i.e. converting fat or amino acids into glucose)
What hormones does the thyroid release?
- Thyroid hormones - T3 and T4
- Calcitonin
What do thyroid hormones do?
It regulates our metabolic rate - the rate at which your cells convert food energy into chemical energy that the cell can utilize (ATP).
What does Calcitonin do?
It promotes uptake of calcium by bone. Lowers blood calcium.
What is the parathyroid?
The parathyroid is 4 little glands on posterior side of the thyroid
What hormone does the parathyroid make?
Parathyroid hormone
What does parathyroid hormone do?
It stimulates bone breakdown to raise blood calcium levels
What are the two sections of the adrenal glands?
- Medulla - inner core
- Cortex - Outer layer
What hormone does the medulla of the adrenal glands make?
Epinephrine
What does epinephrine do?
Works in conjunction with the sympathetic nervous system. Fight or flight.
What hormones does the cortex of the adrenals make?
- Glucocorticoids
- Mineralcorticoids
- Androgens
What are glucocorticoids?
Cortisol - raises blood sugar as part of a stress response
What are mineralcorticoids?
Aldosterone - causes reabsorption of Na+ (sodium) in collecting ducts of nephron.
This is done in response to a drop in blood volume/blood pressure
What are androgens?
DHEA - can be used to make sex hormones
What is the Renin-Angiotensin-Aldosterone Cycle?
It helps increase blood volume and raise blood pressure
What are the steps of the Renin-Angiotensin-Aldosterone Cycle?
- Kidneys secrete renin
- Renin converts angiotensinogen into Angiotensin I
- Angiotensin I goes to lungs where ACE (Angiotensin converting enzyme) converts it to Angiotensin II.
- Angiotensin II stimulate secretion of Alsosterone and ADH which cause constriction of arterioles and to stimulate thirst.
