EXCRETION IN HUMANS Flashcards
What is excretion
the removal of waste products of metabolic reaction, toxic substances and substances in excess of requirements.
What is osmoregulation
this is the control of water content in the body
what does the kidney remove
Urea, excess water and excess salts from the blood
what does the products of the liver create
urine
what happens with water in the kidney
it is regulated depending on what the level is in the blood.
how is this monitored
it is monitored by the brain and a hormone called ADH it used to communicate with the kidney
what artery is connected to the kidney
aorta
what vein is connected to the kidney
renal artery
what connects the kidney to the bladder
ureter
what takes urine out of the body
urethra
what is the renal artery
takes oxygenated blood containing urea and salt to kidneys
what is a kidney
an organ that filters out the blood
what is a bladder
organ that stores urine.
what is a nephron
this is the functional unit of the kidney
what happens in the nephron
it is where filtration of blood takes place
structure of nephron
they are very small, they have their own bloody supply, branching off the renal artery.
what is the bowman capsule
it collects filtrate forced out of the glomerulus and allows to enter kidney tubes.
what is a glomerulus
it filters bloody by increasing pressure to produce filtrate to enter Bowman’s capsule
Convoluted tubules
filtrate flows through these and useful substance in the filtrate are reabsorbed back into the blood capillaries wound around them.
loop of Henle
it maintains water concentrations in the body by filtering out salts
collecting duct
it reabsorbs water back into the blood depending on levels of ADH in blood and collects urine to pass on to the ureter
what is ultrafiltration
all blood is filtered and wall water, urea and salts more into the nephron tubule,
in ultrafiltration what is taken out of blood
water, salts, glucose, urea
first process of ultrafiltration
arterioles branch of the renal artery and lead to each nephron, where they go to the glomerulus sitting inside bowman’s capsule
second process of ultrafiltration
the capillaries get narrower as they get further into the glomerulus which increases the pressure on the blood moving through them.
third process of ultrafiltration
this causes small molecule being carried on the blood forced out of the capillaries and into the bowman’s capsule.
substances taken out if blood during ultrafiltration
glucose, water, urea and salts
where is water reabsorbed at
collecting duct
where is salt reabsorbed at
loop of Henle
where is glucose reabsorbed at
proximal convoluted tubule
where is urea reabsorbed at
not reabsorbed
what comes after the bowman’s capsule
PCT
what comes after the PCT
loop of Henle
what comes after loop of Henle
DCT
what come after the DCT
collecting duct
how is glucose reabsorbed
active transport
how is the nephron adapted for active transport
high number of mitochondria
what is diabetes
people who can’t control their blood Suger levels
if you have diabetes where does urine sometimes go
in their urine
how is water reabsorbed
osmosis
what does ADH do
it lowers the amount of water reabsorbed into the blood
where is ADH created
its is created in the pituitary gland
