The Endocrine System Flashcards
What is the first function of the endocrine system?
Functions to secrete hormones into the bloodstream to regulate many of our bodily functions. Together with the nervous system, they work closely together to regulate and coordinate physiological processes in the body.
What is the second function of the endocrine system?
To provide a chemical system of communication via the bloodstream. It’s a network of glands throughout the body that secrete chemical messengers and deliver them to target sites throughout the body.
What are hormones?
Chemicals released from glands that circulate in the bloodstream and are carried to target structures around the body.
What hormones are released by the pituitary gland?
ACTH, growth hormone and prolactin
What does ATCH do?
It targets the adrenal cortex and stimulates the release of glucocorticoids, which is a key component in the stress response.
What does the growth hormone do?
Produced by the anterior pituitary for the general promotion of cell growth and multiplication.
What does prolactin do?
Produced in the anterior pituitary gland, and it is involved in the production of milk for infants. It regulates the immune system and behaviour.
What does the adrenal gland do?
Produces adrenaline which prepares the body for emergencies, increases heart rate and breathing, raises blood sugar level and diverts blood from the gut to the limbs.
What does the pineal gland do?
It produces melatonin, which affects reproductive development and daily physiologic cycles. More melatonin increases sleep.
What does the pancreas do?
Secretes insulin which converts excess glucose into glycogen in the liver. It then produces glucagon which converts glycogen back into glucose in the liver.
What does the thyroid do?
It secretes thyroxine which controls the rate of metabolism and rate that glucose is used up in respiration and promotes growth.
What is the appraisal of the stressor?
The body appraises the situation using its sensory systems and stored memories. The hippocampus and amygdala to recognise emotional reactions to stimuli and access stored memories for potential danger. The hypothalamus is then alerted which controls the systems that have central roles in the stress response.
What is the sympathomedullary pathway?
Situation is perceived as stressful due to memories, emotions or instincts. The hypothalamus is alerted. This recognises the stress as acute so the SAM pathway is activated. This stimulates the adrenal gland which is situated just above the kidneys. The adrenal medulla secretes the hormones adrenaline and corticosteroids.. These hormones prepare the body for fight or flight.
How does adrenaline affect the body?
Increases perspiration because it regulates body temperature
Dilates pupils because it improves vision
Increases rate of respiration because it increases oxygen intake
Increases heart rate and raises blood pressure because it increases blood flow to organs and spreads adrenaline around the body.
Increases blood flow to muscles for muscular tension because it reduces reaction time.
What happens when we experience a stressor?
Our body activates the autonomic nervous system, specifically the sympathetic branch. This arouses the body and activates the SAM pathway. After a few minutes the parasympathetic branch will be activated, which will reduce the fight or flight response.
