PAPER 2 - BIOPSYCHOLOGY - the endocrine system

Question 1

what is the nervous system?

Answer 1

• consists of nerve cells
• uses nerves to transmit information
• acts by transmitting nerve impulses
• acts rapidly
• direct control
• specific localised effects of neurotransmitters
• short lived effects

Question 2

what is the endocrine system?

Answer 2

• a network of ductless glands throughout the body that manufacture and secrete hormones
• uses blood vessels to deliver hormones to target cells
• acts by release of hormones
• acts slowly
• indirect control

Question 3

what does the endocrine system consist of?

Answer 3

a network of ductless glands and hormones throughout the body
- glands: pituitary, thyroid, adrenal, pancreas, gonads

Question 4

what is the pituitary gland?

Answer 4

• known as the master gland
• many hormones released by the pituitary gland control the secretions from other endocrine glands
• made of 2 main parts (anterior, posterior)

Question 5

what does the anterior pituitary gland do?

Answer 5

releases several hormones which target different parts of the body:
- ACTH - released as part of stress response, stimulates adrenal glands, produces cortisol
- LH & FSH - important in the control of reproductive functioning and sexual characteristics (e.g.. stimulates ovaries to produce oestrogen & progesterone)

Question 6

what are the different parts of the adrenal? glands called

Answer 6

• adrenal medulla (inner part)
• adrenal cortex (outer part)

Question 7

what is the adrenal medulla?

Answer 7

• inner part of adrenal glands
• releases adrenaline and noradrenaline into the bloodstream
• this results in increased heart rate and blood flow to muscles and brain, constriction of blood vessels, increased blood pressure and release of glucose for energy for fight or flight

Question 8

what is the adrenal cortex?

Answer 8

• outer part of adrenal glands
• releases glucocorticoid hormones (e.g. cortisol, cortisone, corticosterone)
• these regulate functions like cardiovascular & inflammatory functions, release of glucose and fats to maintain energy to cope with ongoing stress

Question 9

what are hormones?

Answer 9

chemical substances released from endocrine glands into bloodstream and carried to target sites throughout the body

Question 10

how do hormones stimulate target sites?

Answer 10

• hormones are carried to target sites in the body via the bloodstream
• a hormone can only affect those cells with receptors for that particular hormone (target cells)
• when enough receptor sites are stimulated by hormones then this results in a physiological reaction in target cell
• both levels and timing of release of hormones are critical for normal functioning

Question 11

what is the hypothalamus?

Answer 11

• controls most of the endocrine system
• there are direct connections between hypothalamus and pituitary gland (master gland)
• controls the release of hormones from the pituitary gland

Question 12

how does the hypothalamus control the release of hormones from the pituitary gland?

Answer 12

• signals the pituitary gland by secreting a releasing hormone
• that stimulates pituitary gland to release stimulating hormones into bloodstream
• that stimulates other endocrine glands to secrete their hormones

Question 13

what is the negative feedback system?

Answer 13

• increased in hormone levels are detected by hypothalamus and pituitary gland
• hypothalamus shuts down secretion of releasing hormone
• pituitary gland decreases secretion of stimulation hormone
• this slows secretion of target glands hormone
• results in stable concentration of hormones in bloostream