endocrine system

Question 1

what is a gland

Answer 1

an organ that releases a hormone

Question 2

pituitary gland

Answer 2

known as master gland
regulates other glands
has two lobes with separate functions (anterior and posterior)

Question 3

hypothalamus

Answer 3

controls pituitary hormone production
secretes releasing and inhibiting hormones
links the nervous system and endocrine system
two connections: anterior lobe via special portal blood system
posterior lobe directly via neurons

Question 4

what is the process of releasing a hormone

Answer 4

-neural signal
-hypothalamus releases CRF
-pituitary gland
-production of ACTH
-e.g cortisol released

Question 5

what is CRF

Answer 5

corticotropin releasing factor

Question 6

what is ACTH

Answer 6

adrenocorticotropic hormone

Question 7

what is cushing’s disease, causes and symptoms

Answer 7

-over production of ACTH so adrenal glands over produce cortisol
-causes: tumours/growths in pituitary or adrenal glands
-symptoms: weight gain, red face, red stretch marks, poor WM and poor conc.

Question 8

what is the role of the thyroid

Answer 8

metabolism regulation controlled by pituitary
produces TSH (thyroid stimulating hormone)

Question 9

what occurs with thyroid disregulation

Answer 9

gigantism
-swollen hands and feet
-deepening of voice
-cog. issues
-fertility issues

Question 10

what is grave’s disease

Answer 10

-immune system attacks thyroid gland: hyperthyroidism
-affects 1 in 200
-increased risk of heart failure/stroke
-thinning of skin, inflammation of tissue around eyes which can put pressure on optic nerve

Question 11

what do the ovaries produce

Answer 11

oestradiol (E) and progesterone (P)

Question 12

what do the testes produce and what is their role

Answer 12

testosterone (T)
-essential for reproduction
-controlled by pituitary-produces luteinizing hormone (LH) and follicle stimulating hormone (FSH)

Question 13

what is hypogonadism and its symptoms

Answer 13

low levels of sex hormones
causes impaired fertility and lack of secondary sexual features

Question 14

what is the name of low levels of testosterone

Answer 14

hypoandrogenism

Question 15

what is the name for low levels of oestrogen

Answer 15

hypooestrogenism

Question 16

testosterone and its role

Answer 16

-part of wider group called androgens
-both sexes but 20x more in men
-sexual behaviour, spermatogenesis, developing secondary sexual characteristics, muscle growth

Question 17

what are some possible weaknesses of high testosterone levels

Answer 17

-suppress the immune system
-increased risk of cancer
-aggression
-may reduce parental behaviour

Question 18

evidence of the role of testosterone in animals

Answer 18

Wallen
-castrated rats fail to show sexual behaviours but can be reinstated using implants
-anti androgens reduce male sexual behaviours

Question 19

natural experiments demonstrating role of T in humans

Answer 19

Wang et al 2000
-hypogonadal men with reduced sexual functioning, poor mood, lower muscular strength
-wear T patch for 180 days
-sexual performance and desire increases @30 days
-increase of mood @30 days
-increase in leg press

Question 20

evidence that T levels can be influenced by social cues

Answer 20

Midgley
-60% of those that take steroids show anticipation of sexual activity increases T levels

Question 21

lab controlled experiment into T

Answer 21

Nave et al 2017
-T gels cause men to make rash decisions and choose obvious incorrect answer instead of thinking carefully about correct answer

Question 22

oestrodiol (E) and its role

Answer 22

-in both sexes but 8x more in women
-sexual behaviour, secondary sexual characteristics, skin elasticity, sensitivity of brain to oxytocin
-regulates ovulation, positive bone density/strength, positive mood/wellbeing, regulates pregnancy

Question 23

do E levels vary or remain constant

Answer 23

vary across menstrual cycle
works in conjunction with progesterone

Question 24

evidence of effect of E on behaviour

Answer 24

Takahashi
-ovariectomised rats are not sexually receptive
-can be reinstated with large doses of E
-more effective to give small amounts of E with P (progesterone)
-E has a priming effect in hypothalamus causing lordosis (curving of spine) (Pfaff 1989)

Question 25

natural experiments on women (E)

Answer 25

Nathorst-Boos et al 1993
-women going through menopause have decreased hormones
-women wear E patch for 90 days
-increase desire for sex and reduce pain by lubrication
-also improves sleep after 90 days (Polo Kantola 1998)

Question 26

role of T in menopause

Answer 26

Cappelletti and Wallen found T can help increase sexual desire following menopause

Question 27

what are activational effects

Answer 27

-immediate effects that come and go
e.g ovulation, oxytocin release during orgasm

-may cause some structural change, hippocampus can shrink in absence of some hormones (Fitch and Denenberg)

Question 28

what are organisational effects

Answer 28

-permanent effects on structure and function of body and NS
-critical period of development e.g fetal/puberty

Question 29

activational sex hormone regulation

Answer 29

hypothalamic pituitary gonadal axis (HPG axis)
-gonadotropin releasing hormone GnRH
-follicle stimulating hormone
-luteinizing hormone

Question 30

activational sex hormone regulation in men

Answer 30

GnRH bursts - 2 hours
T provides negative feedback loop to hypothalamus and pituitary

Question 31

activational sex hormone regulation in women

Answer 31

GnRH varies over 28 days as does:
-pituitary sensitivity to GnRH
-ovary sensitivity to LH/FSH
-LH and FSH crucial to ovulation

Question 32

organisational effects: sex hormones

Answer 32

-presence of SRY gene determines male sex, this is a region of the Y chromosome
brain effects/development
-womens brains share functions bilaterally
-mens are slightly larger overall

Question 33

early sex differences in behaviour study

Answer 33

Connellan 2000
-babies 37 hrs old
-shown face or a mobile image for 70 secs
-blind judges guess sex of baby by their observation of the image presented
- 43% boys prefer mobile image compared to 17% for girls
- 25% boys prefer face compared to 36% for girls

Question 34

oxytocin (OT) and behaviour

Answer 34

-known as cuddle hormone
-in female prairie voles injection of OT antagonist inhibits pair bonding
-OT directly into brain = pair bonding without mating