Homeostatic & Response - The Endocrine System Flashcards
what are hormones
chemical messengers which travel in the blood to activate target cells
what type of glands are hormones produced and secreted by
endocrine glands
why do we have a endocrine system
so we can react to changes in the environment and changes inside our body
pituitary gland
sometimes called the master gland cus hormones rom it act on other glands
what does the pancreas make
insulin which is used to regulate the blood glucose levels
what does the thyroid make and what is it used for
thyroxine which regulates metabolism, heartrate and temperature
compare the action of nerves and hormones
nerves are faster
nerves act for a shorter time
hormones act in a more general way where as nerves work on a precise area
what the the process of insulin lowering blood sugar levels
rise in blood glucose is detected by the pancreas
pancreas produces insulin into the blood
insulin causes cells to take up more glucose
cells in liver and muscles can convert it into a storage molecule called glycogen
this causes blood glucose leel to fall
how does glucagon increase blood sugar levels
pancrwase detects fall in blood glucose and produces glucagon
glucagon causes glycogen to be converted back into glucose which enters the blood and causes blood glucose to rise
what is type 1 diabetes
condition where pancreases produces little or no insulin so persons blood glucose can rise to a level that can kill them
how can type one diabetes be controlled with insulin therapy
several injections of insulin into the blood throughout the day usually at meal times.
the amount needed depends on the persons diet and how actie they are
how can a diet be used to control type one diabetes
limit intake of foods that are rich in simple carbs. spread intake of starchy food throughout the day. eat food that is absorbed more slowly
how does regular exercise help control type one diabetes
lower blood glucose and increases cell metabolism
what are the benefits of making human insulin from genetic engineering as oppose to it being extracted from the pancreases of pigs and cows
doesn’t cause adverse reactions.
no animals die.
what is type 2 diabetes
insulin resistance
how can type 2 diabetes be controlled
carb controlled diet
regular exercise
what are 2 modern type 1 diabetes treatment methods
pancreases transplant
resseach into artifical pancreas and stem cells could stop organ rejectionartid
how can diabetes be tested for
looking for glucose in urea sample
blood test to confirm dianosiss. blood test is more reliable cus it gives current levels of glucose in the blood
how are substances in urine filtered out if the blood
filtration as blood goes through the kidneys
what is selective reabsorption
after filtration the right amounts of substances are filtered back into the blood
what are 3 substances removed from the body in urine
excess water and ions and urea
why does there have to be the right balance between water and ions in the blood
so the right amount of water is taken into the cells in osmosis
what is deamination
amino acids cannot be stored can they are converted into fats and carbs in the liver which can be stored. ammonia is produced as a waste product
ammonia is produced in deamination. what is done w it then
its toxic so converted to urea in the liver, then the ureA IS TRANSPORTED TO THE KIDNEYS AND FILTERED OUT OF BLOOD AND EXXTRETED
what is the name of the structure that filtration and selective reabsorption happens in in the liver
tubules
what happens if the water content in the blood becomes to low
brain monitors the content of the blood and see its too low. It instructs the pituitary gland to release more anti diuretic hormone so tubules become more permeable so more water is reabsorbed. this is negative feedback
how does a dialysis machine work
persons blood flows along beside a partially permeable membrane surrounded by dialysis fluid. The dialysis fluid has the right concentration of dissolved ions as healthy blood
give 5 problems w dialysis
3 times a week for 3 to 4 hours so not nice experience
can lead to infection and cause blood clots
patients have to be carful about what they eat so a certain ion doesn’t build up between sessions
patients have to limit their fluid intake to stop fluids building up inside them
expensive
kidney transplants are the only cure for kidney disease but what is a problem w it and explain the problem
kidney can be rejected by recipients immune system
this happens when antigens on the kidney are not recognized as being part of the body by the recipients white blood cells so they produce antibodies to attack the donor cells
how can kidney transplant rejection be prevented
donor with similar tissue type ( w similar antigens)
immune supressing drugs to reduce production of antibodies and white blood cells
