Adrenal gland Flashcards
What are the roles of the adrenal glands?
Responding to acute and chronic stress.
What type of stress might the adrenal glands respond to?
Infection, intense temperatures, prolonged exercise, sleep deprivation, fright, emotional stress.
What does the medulla secrete?
Epinephrine and noepinephrine (adrenaline and noradrenaline).
What are the three zones of the outer cortex region of the adrenal gland?
Mineralocorticoid, glucocorticoid and androgen precursors.
What is an example of a mineralcorticoid?
Aldosterone.
What is an example of a glucocorticoid?
Cortisol.
What is an example of androgen precursors?
Dehydroepiandosterone.
What effects do catecholamines cause?
Bodily symptoms (adrenaline).
What effects do glucocorticoids cause?
Metabolic effects.
What effects do mineralocorticoids cause?
Sodium effects - blood volume.
What part of the nervous system is the adrenal medulla a part of?
Sympathetic division of the autonomic nervous system.
What type of neurones makes up the adrenal medulla?
Postganglionic neurones.
What is secretion from the adrenal medulla controlled by?
Sympathetic preganglionic nerve fibres.
What is the fight-or-flight response?
Activation of the sympathetic nervous system during stress - release of adrenal medullary hormones.
What is the process in which adrenal catecholamines are released?
The hypothalamus is stimulated by stress, physical activity or low blood glucose which sends action potentials through the sympathetic division of the autonomic nervous system which causes the adrenal medulla to release adrenaline and noradrenaline.
What are mineralocorticoids synthesised from?
Cholesterol.
What is cortisol synthesised from?
17-hydroxy-pregnenolone