Endocrine System Flashcards
What does the parasympathetic system do? (9)
- Constrict pupils
- Stimulate saliva
- Slow heartbeat
- Constrict airways
- Stimulate activity of stomach
- Inhibit glucose release
- Stimulate intestinal activity
- Contract bladder
- Promote erection
What does the sympathetic system do? (10)
- Dilate pupils
- Inhibit salivation
- Increase heartbeat
- Relax airways
- Inhibit activity of stomach
- Stimulate glucose release
- Inhibit intestinal activity
- Secrete adrenaline and noradrenaline
- Relax bladder
- Promote ejaculation and vaginal contraction
True or false: sympathetic nerve fibres innervate all vessels except capillaries and precapillary sphincters which follow local control
TRUE
Complete the sentences:
Sympathetic division prioritises blood vessels to ______, _________ ________ and ______ in times of emergency. Blood vessels to skin _____________ to minimise bleeding if injury occurs during stress or exercise
Brain
Skeletal muscles
Heart
Vasoconstrict
What does venoconstriction increase?
Cardiac return
What are examples of neurocrine communication? (3)
Anterior pituitary
Posterior pituitary
Adrenal medulla
What are the major endocrine glands/organs? (9)
Pineal gland Thyroid gland Parathyroid gland Adrenal glands Gonads Hypothalamus Pituitary gland Thymus Pancreas
What does the thymus produce that promotes T cell maturation?
Thymosin
What do hormones control and regulate? (5)
- Reproduction
- Metabolism
- Growth and development
- Body defences
- General homeostasis and water, nutrient and electrolyte balance of blood
Which is the point at which the CNS and endocrine system communicate?
Hypothalamus
What does the hypothalamus deal with? (7)
- Thermoregulation
- Plasma osmolality via osmoreceptors
- Heart rate and BP
- Feeding
- Sleep
- Emotion, sexual behaviour
- Lactation
What does the hypothalamus produce? (2)
- ADH and oxytocin (brings about contraction of uterus and release of milk)
- 6 hormones that travel via hypothalamo-hypophyseal portal system to anterior pituitary (4 stimulatory, 2 inhibitory)
What is another name for the pituitary gland?
Hypophysis
What are the two lobes of the pituitary called?
Anterior
Posterior
Neurones that produce hormones are released from which lobe of the pituitary gland?
Posterior
What are the two portal systems in humans?
Hepatic portal system
Hypothalamo-hypophyseal portal system
Which hormone does the thyroid produce?
Thyroxin
What is TRH?
Thyrotropin-releasing hormone
What is TSH?
Thyroid stimulating hormone
Which responses are involved in the ‘stress response’? (3)
Endocrine
Nervous
Immune
Behavioural effects of the stress response include what? (4)
Increased awareness
Improved cognition
Euphoria
Enhanced analgesia
What are the physiological adaptions initiated by activation of the stress response?
Increased CV tone
Increased resp rate
Intermediate metabolism
Inhibition of feeding, digestion, growth, reproduction and immunity
Complete the sentence:
The principal effectors of the stress response are localised in the ___________, ________ lobe of the pituitary gland and the _________ gland
Hypothalamus
Anterior
Adrenal
What are the adrenal cortical hormones? (2)
Glucocorticoids (cortisol)
Mineralocorticoids (aldosterone)
What is the central portion of the adrenal gland called?
Medulla
What is the central portion of the adrenal gland composed of?
Parenchyma of large, pale-staining epithelioid cells called chromaffin cells
What are chromaffin cells?
Modified neurones
Complete the sentences:
When nerve impulses carried by the sympathetic fibres reach the catecholamine-secreting chromaffin cells, they release their secretory products, ____________ and ______________. Therefore, chromaffin cells are considered the equivalent of _______________ neurones
Adrenaline
Noradrenaline
Postsynaptic
Why are chromaffin cells considered as neurocrine secretion?
They are equivalent to postsynaptic neurones and secrete into the bloodstream
What are the effects of adrenaline and noradrenaline? (5)
- Glycogen breaks down to glucose
- Increased BP
- Increased breathing rate
- Increased metabolic rate
- Change in blood flow patterns, increased alertness and decreased digestive/excretory/reproductive active
What does the pineal gland produce?
Melatonin
What does melatonin do?
Involved in control of circadian rhythm
What inhibits melatonin release?
Light exposure
What does melatonin inhibit?
Release of gonadotrophins (LH and FSH)
True or false: the pineal gland calcifies in early adulthood and can be seen on skull x-rays
TRUE
