Endocrine system Flashcards
What is the role of the parasympathetic system
Rest and digest
What are the effects of the parasympathetic system
Constricted pupils, salvia, slower heart beat, constrict airways, stimulate stomach activity, inhibit glucose release
What is the role of the sympathetic nervous system
Fight or flight
What are the effects of the sympathetic nervous system
Dilate pupils, inhibit saliva, increase heart rate. Relax airways. Inhibit digestion, secrete adrenaline and noradrenaline, release glucose
What is neurocrine communication
When nerve cells secrete hormones directly into the blood
Where does neurocrine secretion occur in th body
Anterior pituitary, posterior pituitary and adrenal medulla
What are the 9 endocrine glands
Pineal, thyroid, parathyroid, adrenal, gonads, hypothalamus, pituitary, thymus, pancreas
What is the role of the thymus
Produces thymosin that promotes T cell maturation during thymic cell education
Where is the thymus located
Superior mediastinum
What hormones are released from the hypothalamus to travel to the posterior pituitary
ADH and oxytocin
How many hormones travel via the hypothalamo-hypophyseal system to the anterior pituitary
6
Name 2 gland which are involved in the hypothalamo-hypophyseal portal system
Thyroid and adrenal
For control of the thyroid gland what hormone is secreted by neurones in the hypothalamus
Thyroid releasing hormone
TSH causes the release of which hormone in the anterior pituitary gland
TSH (thyroid stimulating hormone)
What does the adrenal cortex release
Cortical hormones:
- Glucocorticoids (cortisol)
- Mineralocorticoids (aldosterone)
What do cortical hormones cause
Increase in blood pressure and increase in glucose in the blood stream
What hormone is released by neurones from the hypothalamus to control the adrenal cortex
Corticotopin releasing hormone
What is released from the anterior pituitary gland in response to CRH
Adrenocorticotropic hormone
What does ACTH cause
The release of cortisol from the adrenal cortex
How is the hypothalamo-hypophyseal portal system control of the adrenal cortex and thyroid gland involved in negative feedback
The hormones released from either the thyroid or adrenal cortex inhibit the release of hormones in the hypothalamo-hypophyseal portal system
What is the adrenal medulla composed of
Chromaffin cells (modified neurones)
What do chromaffin cells secrete
Catecholamines
What is the role of the pineal gland
Produces melatonin which controls your bloody clock, inhibit release of gonadotrophins
What happens to the pineal gland with age
It calcifies
Why can the adrenal medulla be considered in neurocrine secretion
The nerve cells composing the adrenal medulla secrete hormones into the blood
What is the effects of adrenaline and noradrenaline
Increased heart rate, increased blood pressure, conversion of glycogen to glucose, dilation of bronchioles and increased metabolic rate
What do mineralocorticoids do
Retain dosing and water in the kidneys, increasing blood volume and pressure
What do glucocorticoids do
Increase blood sugar level
What is the stress response
A state of real of perceived threat to homeostasis
What does the renin-angiotensin-aldosterone system do
increases blood pressure and volume
Where is angiotensinogen produced
Liver
What converts angiotensinogen into angiotensin I
Renin
What converts angiotensin I into angiotensin II
Angiotensin converting enzyme (ACE)
What does angiotensin II do
Causes ADH secretion, vasoconstriction and causes the release of aldosterone from the adrenal gland
Where is renin secreted
Kidneys
What does aldosterone do
Causes the retention of salt and water in the kidneys
