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level: 6.6 Homeostasis

Questions and Answers List

level questions: 6.6 Homeostasis

QuestionAnswer
How does thyroxin work?increases metabolic rate by oxidation of carbohydrate + fatty acids produces heat = controls body temp
How does thyroxin work?increases metabolic rate by oxidation of carbohydrate + fatty acids produces heat = controls body temp
What is homeostasis?maintaining a constant internal environment for optimal functioning. This involves body temp and fluids
Where is melatonin made? use? response to?pineal gland - controls biological clock responds to light = signal to hypothalamus
Where is ADH made? use?pituitary gland - osmoregulation
Where is thyroxin made? use? signalled by?thyroid gland bec of signal from hypothalamus - metabolic rate
Where is adrenaline made? use?adrenal gland - fight/flight
where is insulin and glucagon made? use? where in the body does it act on?pancreatic pits (islets of Langerhans) pancreas - sugar levels act on the liver
Where is leptin made? use? binds to?adipose tissue - inhibits appetite binds to receptors in hypothalamus
Where is testosterone and estrogen made? use?leydig cells and ovaries - sex characteristics
When is insulin released? where is it released from? what happens? (3)when glucose levels are high (after eating) released from beta cells causes glycogen synthesis in liver = glucose uptake by liver + adipose tissue
When is glucagon released? where? what happens? (3)alpha cells of pancreas when glucose levels are low ( after exercise) breakdown glycogen = releases glucose
Difference bw type 1 + type 2 diabetes? treated by?t1 = no producing insulin = insulin injections destruction of b cells t2 = no response to insulin = diet down regulation of insulin receptors
How does thyroxin work?increases metabolic rate by oxidation of carbohydrate + fatty acids produces heat = controls body temp
What increases/ decreases leptin production?overeating = more adipose cells = more leptin starvation = less adipose = hunger
Who has leptin resistance? why? side effects?obese = desensitized bec of high levels of leptin = feel more hungry = overeat older = weight gain skin irritations
What were the results in the mice experiments? (2)leptin gene mutation + healthy = leptin transferred to obese = lost weight defective leptin receptor + healthy = leptin to healthy mouse bec obese mouse overproduced = obese mouse remained the same but healthy bec thin bec of too much leptin
what happens during jet lag? symptoms? (2)change in circadian rhythms from travelling and diff time zones fatigue, headaches but only lasts a few days
soil and seed theory? William Harvey?male = seed mixes with menstrual blood (soil) = fetus develops from info from the seed (Aristotle) william harvey = investigated 7 week pregnant deer and couldn't detect the embryo before that - debunks theory
What is the SRY gene? what does it do? what does it code for?sec determining region Y from the Y chromosome causes male characteristics codes for TDF (testis determining factor) = forms testes
What is the role of testosterone? (2)develops male genitals sperm production secondary characteristics (body hair, muscle, deeper voice)
What is the role of estrogen and progesterone?female organs secondary characteristics menstrual cycle
label a pp + use of each part (6)van deferens: moves sperm from testes to prostate gland urethra: semen to outside seminal vesicle: fructose for sperm, mucus to protect sperm, prostaglandin to cause uterine contractions prostate gland: alkaline fluid to neutralise vaginal acids testis: produce sperm + testosterone epididymis: sperm matures and is stored here (scrotum, penis, erectile tissue, ureter, bladder)
label a vg + use (5)ovaries: oocytes mature before release + secretes estrogen + progesterone fimbriae: move oocyte into oviduct fallopian tube: oocyte to uterus (fertilisation occurs here) uterus: fertilised egg implants and develops endometrium: thickens to prepare for implantation
What do FSH, LH, Estrogen and progesterone do?FSH: follicular growth = estrogen secretion from developing follicles LH: ovulation = forms corpus luteum = anterior pituitary Estrogen: thickens edometrium lining, inhibits fsh and lh + stimulates before ovulation progesterone: thickens endometrium + inhibits fsh and lh
describe the menstrual cycle? (all steps nd hormones involved in order) (5)1. FSH grows follicles = produces estrogen = inhibits FSH (-) = prevents other follicles to grow = thickens endometrium lining 2. before ovulation estrogen causes pituitary to secrete LH and FSH again. LH causes follicle to rupture and release 2nd oocyte = ovulation 3. ruptured follicle = corpus luteum = secretes a lot of progesterone + little estrogen = thickens endo wall. P and E inhibit FSH and LH 4. corpus luteum degenerates (corpus albicans) = E + P levels drop = endo wall removed cycle repeats bec e+p are too low to inhibit FSH and LH
What happens with ivf? STOP SUPEREGG FARTING PROTEIN IMPLANTS (5)1) STOP hormones (FSH and LH) = no cycle with drugs 2) SUPEROVULATION =(FSH = many follicles + HCG produce by embryo = follicle matures 3) EGG collected before it ruptures 4) FERTILISATION with sperm 4) PROGESTERONE DRUGS treatment 2 weeks prior = develops endometrium 5) IMPLANTED