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location of pituitary gland
brain
hormones produced in pituitary gland
FSH
LH
role of FSH hormone
stimulates oestrogen production
stimulates growth of follicles in ovaries
role of LH hormone
stimulates ovulation
location of thyroid gland
neck
hormone produced in thyroid gland
thyroxine
role of thyroxine
stimulates the metabolic rate
how does thyroxine control the metabolic rate
controls rate at which
oxygen and food products react
to release energy for the body to use
location of pancreas
abdomen
hormone produced in pancreas
insulin
role of insulin
stimulates muscles and liver
to take up excess glucose
from the bloodstream
to store as glycogen
what is glycogen
glucose polymer
location of adrenal gland
abdomen
hormone produced in adrenal gland
adrenaline
role of adrenaline
increase heart and breathing rate
divert blood flow towards muscles
dilation of blood vessels inside muscles
breaking down glycogen to glucose
dilation of pupils
how does adrenaline increase the heart and breathing rate
ensures glucose and oxygen
delivered to muscles cells
and carbon dioxide taken away
from muscles cells
at increased rate
why does adrenaline divert blood flow towards muscles
ensures an increased supply of reactants of respiration
reach the muscles
to prepare the body for movement
why does adrenaline dilate blood vessels in muscles
ensures an increased supply of reactants of respiration
reach the muscles
to prepare the body for movement
why does adrenaline break down glycogen into glucose
to increase blood glucose concentration
for increased respiration
in muscle cells
why does adrenaline dilate the pupils
to allow as much light as possible
to reach the retinas
so more information can be sent to the brain
location of testes
scrotum
hormone produced in testes
testosterone
role of testosterone
stimulates sperm production
location of ovaries
lower abdomen
hormone produced in ovaries
oestrogen
role of oestrogen
grows and repairs uterine lining
hormone produced in corpus luteum
progesterone
role of progesterone
maintains the uterine lining
creates a mucus plug in cervix
state thyroid gland negative feedback loop
hypothalamus detects low levels of thyroxine
and releases more TRH
stimulating release of TSH in pituitary gland
stimulating thyroid gland to release thyroxine
normal or high levels of thyroxine inhibits release of TRH
which inhibits the release of TSH, inhibiting the release of thyroxine
role of TRH
stimulates the release of TSH
role of TSH
stimulates thyroid gland to release thyroxine
menstrual cycle stages
menstruation
uterine lining thickens
ovulation
lining is maintained in case of pregnancy
why contraception is used
to keep families small
limit the increase of the human population
state natural forms of contraception
abstinence
rhythm method
state chemical forms of contraception
IUD
contraceptive pill/implant/injection
explain how IUDs work to prevent contraception
release progesterone
causes mucus plug to form in cervix
makes it difficult for sperm to enter uterus
also thins uterine lining
so fertilised egg are less likely to implant
evaluate IUDs
explain how contraceptive pills/implants/injections work to prevent contraception
contains progesterone
progesterone inhibits FSH and LH
FSH is inhibited meaning no new eggs are produced by ovary follicles
LH is inhibited meaning ovulation cannot occur
meaning the sperm can’t fuse with an egg
state barrier forms of contraception
condom
femidom
diaphragm + spermicide
explain how a condom/femidom works to prevent contraception
physically prevents sperm from meeting the egg
explain how diaphragm + spermicide work to prevent contraception
diaphragm physically prevents sperm from entering the uterus through the cervix
spermicide kills any sperm present
state advantages of hormonal contraception
effective when taken regularly
more effective than barrier methods as it prevents ovulation
state disadvantages of hormonal contraception
doesn’t protect from STIs
lacks effectiveness when not taken regularly
can produce unwanted side effects
state advantages of barrier method contraception
protects from STIs
no side effects on the body (e.g. affecting the menstrual cycle)
state disadvantages of barrier contraception
less effective than hormonal methods
barrier methods are only effective when used correctly
infertility definition
when a couple find it difficult or unable to conceive naturally
causes of infertility
issues with female reproductive system
insufficient levels of reproductive hormones affecting the development of gametes
explain use of hormones in Assisted Reproductive Technology (ART)
IVF is an example of ART
IVF gives the female FSH and LH to stimulate the development and release of matured egg cells
the egg cells are collected from the female and fertilised with the male’s sperm in a lab
fertilised eggs develop into embryos
the embryos are inserted into the female’s uterus
explain use of hormones in clomifene therapy
clomifene drug is given to the female to cause more FSH and LH to be released
which stimulates the development and release of matured egg cells
state advantage of fertility treatment
can provide an infertile couple with a baby
state disadvantages of fertility treatments
expensive
risk of multiple births
low success rate
ethical issues as it could increase the risk of eugenics
explain the importance of maintaining internal conditions in response to internal/external factors
ensures that reactions in bodily cells can function normally
thermoregulation definition
maintenance of core body temperature
explain the importance of homeostasis in thermoregulation
human body needs to maintain optimum temperature
for optimum enzyme activity within bodily cells
state example process of thermoregulation
respiration
releases thermal energy from the body
into the surroundings
state body part where thermoregulation occurs
hypothalamus
explain what occurs if body temperature is too high
hair erector muscles relax
vasodilation (blood vessels dilate)
causing sweat to be secreted by sweat glands into the skin
sweat evaporates, cooling the skin
thermal energy from the body is lost
explain what occurs if body temperature is too low
hair erector muscles contract
erected hair traps air which acts as an insulator
vasoconstriction (blood vessels constrict)
causing sweat to stop
and skeletal muscles to contract (shivers)
osmoregulation definition
maintenance of water and salt concentrations across membranes within the body
explain the importance of homeostasis in osmoregulation
maintaining water concentration in the body is important
to prevent harmful changes occurring to bodily cells due to osmosis
explain what occurs if water concentration is too high
causes cells to be in a hypotonic solution
where excess water enters them due to osmosis
causing the cells to swell and eventually lyse (burst)
explain what occurs if water concentration is too low
causes cells to be in a hypertonic solution
where cells lose excess water due to osmosis
causing the cells to shrivel and cause cell death
explain the role of the dermis in thermoregulation
dermis contains sweat glands, hair erector muscles and blood vessels
which change to maintain the optimum core temperature of the body
explain the role of the hypothalamus in thermoregulation
the hypothalamus maintains the optimum internal temperature of the body
by making changes in the body based on internal changes in temperature
explain how insulin controls blood glucose concentration
hypothalamus detects high blood glucose concentration
triggering the pancreas to release insulin
insulin stimulates the liver and muscles cells to take up excess glucose from the blood
and store it as glycogen
explain how glucagon controls blood glucose concentration
decreased blood glucose concentration triggers the pancreas to release glucagon
glucagon stimulates the liver to break down glycogen into glucose
which is released into the bloodstream
what is glycogen
glucose polymer
explain the cause of type 1 diabetes
the patient’s pancreas fails to produce sufficient insulin to control blood glucose concentration
causing uncontrollable high blood glucose concentrations
explain how type 1 diabetes is controlled
insulin injections
to decrease blood glucose concentrations
explain the cause of type 2 diabetes
the patient’s cells become resistant to insulin produced by the pancreas
causing uncontrollable high blood glucose concentrations
explain how type 2 diabetes is controlled
low-carbohydrate diet
regular exercise
evaluate the correlation between body mass and type 2 diabetes
obesity is a major risk factor for type 2 diabetes
because an obese person is more likely to eat a carbohydrate-dense diet
causing the over-production of insulin
resulting in the development of insulin-resistance
evaluate the correlation between waist: hip ratio and type 2 diabetes
a waist: hip ratio closer above 0.85/1.0 indicates fat being stored abdominally
which suggests obesity caused by a carbohydrate-dense diet
causing the over-production of insulin
resulting in the development of insulin-resistance
evaluate the correlation between BMI and type 2 diabetes
a BMI above 30 indicates that a person is obese
which suggests obesity caused by a carbohydrate-dense diet
causing the over-production of insulin
resulting in the development of insulin-resistance
state how to calculate BMI
mass (kg) / height² (m)
state how to calculate waist: hip ratio
waist circumference (cm) / hip circumference (cm)
state the waist: hip ratio obesity indicator in men
1.0 +
state the waist: hip ratio obesity indicator in women
0.85 +
state functions of urinary system
ultrafiltration of blood
selective reabsorption
osmoregulation
excretion of metabolic waste products
state what urinary system consists of
two kidneys
joined to the bladder
by two tubes (ureters)
and to the vena cava by the renal vein
the renal artery supplies oxygenated blood to the kidneys
and a urethra carries urine from the bladder outside of the body
kidneys function
osmoregulation of water in blood (vital for maintaining blood pressure)
excrete metabolic waste products
ultrafiltration of blood
selective reabsorption of key substances
kidneys structure
cortex - outer region
medulla - inner section
renal pelvis - tube linking kidney to the ureter
state location of nephrons
kidneys
state what nephrons are made of
kidney tubule
state sections of a kidney tubule
glomerulus
Bowman’s capsule
proximal convoluted tubule
loop of Henlé
distal convoluted tubule
collecting duct
state the small molecules filtered by the nephron
urea
amino acids
salts
glucose
water
state which small molecule is not reabsorbed by the nephron
urea
state the large molecules which are not filtered by the nephron
proteins
cells
explain how the nephron is related to filtration in the glomerulus and Bowman’s capsule
nephron contains capillaries that are ‘leaky’ due to small spaces between cells in their walls
Bowman’s capsule is the first part of the nephron and the cells which make it up have spaces between them
this means molecules can enter from the capillaries
blood flow through high pressure glomerulus causes small molecules to pass through capillary walls
where the larger molecules remain in the blood
explain how the nephron is related to the selective reabsorption of glucose
in the glomerulus and Bowman’s capsule, glucose is forced out through small gaps between cells in their walls
in the proximal convoluted tubule, all the glucose is actively transported back into the blood
by proteins in the cell membrane
explain how the nephron is related to the reabsorption of water
water is filtered out of the blood through small gaps between cells in the walls of the glomerulus and Bowman’s capsule
in the loop of Henle, water is reabsorbed due to osmosis
due to the high concentrations of salts and mineral ions in the surrounding tissue
explain the effect of ADH on the permeability of the collecting duct when water content in the blood is too high
osmoregulation is controlled by ADH
which is released by the pituitary gland
by controlling the permeability of the collecting duct
the hypothalamus detects that water content in the blood is too high
signalling the pituitary gland to release less ADH
making the collecting duct becomes less permeable and thus reabsorbs less water
explain the effect of ADH on the permeability of the collecting duct when water content in the blood is too low
osmoregulation is controlled by ADH
which is released by the pituitary gland
by controlling the permeability of the collecting duct
the hypothalamus detects the water content in the blood is too low
signalling to the pituitary gland to release more ADH
making the collecting duct more permeable and thus reabsorbs more water
what does ADH stand for
antidiuretic hormone
causes of kidney failure
severe blood loss (in an accident)
high blood pressure
diabetes
impacts of kidney failure
toxins build up in the kidneys
which can enter the bloodstream
and cause death
describe the process of kidney dialysis to treat kidney failure
unfiltered blood is taken from an artery in the arm (containing urea)
and pumped in the dialysis machine where it returns to a vein in the arm
dialysis fluid and the blood are separated in the machine by a partially permeable membrane
the blood flows in the opposite direction to the dialysis fluid
allowing the exchange of molecules between concentration gradients to exist
urea will diffuse across the partially permeable membrane
due to the large concentration gradient (caused by the fluid having no urea)
meaning clean, filtered blood is now being pumped back into the vein
describe the process of kidney donation to treat kidney failure
one healthy kidney is taken from a genetic match
and transplanted into the patient to replace BOTH of their unhealthy kidneys
state what dialysis fluid contains
glucose concentration similar to normal blood level
concentration of salts similar to normal blood level
no urea
what process produces urea
breakdown of excess amino acids in the liver
Note 
Flashcard (102)