M5 excretion Flashcards
what is excretion?
the removal of waste products of metabolism from the body
e.g. CO2 is a waste product of respiration, too much in blood is toxic so is removed by lungs
what is the process of excess amino acids being broken down by the liver
deamination and ornithine cycle
what is detoxification and what are 2 examples?
when the liver breaks down harmful substances into less harmful components that can be excreted from the body
alcohol (ethanol) and insulin
what does the hepatic artery do?
supplies the liver with oxygenated blood from the heart
what does the hepatic vein do?
takes deoxygenate blood away from the liver
what does the hepatic portal vein do?
brings blood from the duodenum and ileum so its rich in products of digestion
what does the bile duct do?
takes bile to the gall bladder to be stored
what do Kupffer cells do?
remove bacteria and break down old red blood cells
what are hepatocytes?
cylindrical structures made of cells that break down harmful substances into less harmful substances that can re enter the blood
what are sinusoids?
capillaries that connect hepatic artery and hepatic portal vein to the central vein.
under a light microscope, what are the white spaces?
sinusoids
under a light microscope, what is the large white circular shape?
central vein
under a light microscope, what are the cells that radiate out of central vein?
hepatocytes and the red dots are nuclei
what can kidney failure be detected by?
measuring the glomerular filtration rate, the rate at which blood is filtered from the glomerulus into the bowman’s capsule
how can kidney infections cause kidney failure?
it cause inflammation of kidneys, which can damage parts of cell. this interferes with filtering in the bowman’s capsule. or with reabsorption in other parts of the nephrons
how can high blood pressure cause kidney failure?
damages the glomeruli, the blood in the glomeruli is already under high pressure and the capillaries can be damaged if the blood pressure gets too high meaning larger molecules like proteins can get through the capillary walls and into the urine
what can long term kidney failure cause?
anaemia - lack of haemoglobin in the blood
swelling - fluid accumulates in tissues
vomiting - too much urea in blood
weight loss - too much urea in blood
what is haemodialysis?
when a patients blood is passed through a dialysis machine. the blood flows on one side of a partially permeable membrane and dialysis fluid on the other side
what are 2 disadvantages of haemodialysis?
long sessions, 3/5 hours
usually in hospital
patients can feel increasingly unwell in between sessions
what is peritoneal dialysis?
dialysis fluid is put through a tube that passes from the outside of a patients abdomen into their abdominal cavity. waste products diffuse out of the patients blood into dialysis fluid across the peritoneum. after some time the fluid is drained out via the tube
what are 2 disadvantages of peritoneal dialysis?
risk of infection
no dialysis free days
several times a day or overnight
at comfort of your own home
what is a kidney tranplant?
where a new kidney is implanted into a patients body to replace a damaged kidney
what are 3 disadvantages of kidney transplant?
risky
immune system might reject , so drugs need to taken to supress this
person with same blood and tissue type hard to find
not always get an organ donor, long wait
what is the hormone that is found in the urine of pregnant women?
hCG
human chorionic gonadotropin
how can urine be tested for steroids?
by gas chromatography/mass spectrometry
