the excretory system Flashcards
what are the wastes produced by the lungs liver sweat glands and kidneys
lungs the excretion of carbon dioxide produced by cell respiration
liver processes substances that must be excreted
sweat glands the skin secretes sweat which is largely water for cooling sweat also includes by products of metabolism the skin secretes 500 mls of water a day
kidneys are the principle of the excretory system they are responsible for maintaining constant concentration of materials and body fluids
What is the word equation for deamination and which organ excretes Urea
Amino acid + oxygen -> carbohydrate + ammonia
Area is excreted by the kidneys
Describe how the structure of the kidney is ideally suited to the kidney’s function
There are a large number of nephrons/about 1.2 million nephrons per kidney (1 mark) to allow a large amount of blood to be filtered and urine to be produced (1 mark)
The glomerulus acts as a semipermeable membrane (1 mark) so that only water and dissolved solutes enter the Bowman’s capsule (1 mark)
The glomerulus is surrounded by the Bowman’s capsule (1 mark) to allow for the collection of filtrate (1 mark)
The blood in the glomerulus is only separated from the Bowman’s capsule by a small number of thin cells (1 mark) which facilitates diffusion (1 mark)
The renal tubule is very long (1 mark) to provide a large surface area for reabsorption (1 mark)
The renal tubule is surrounded by a network of blood capillaries (1 mark) to allow for reabsorption (1 mark)
The afferent arteriole is wider than the efferent arteriole (1 mark) to increase the blood pressure in the glomerulus, increasing filtration (1 mark)
Cells of the renal tubule have large numbers of mitochondria (1 mark) to provide energy for active reabsorption (1 mark)
what is deamination
the removal off the amino group from the amino acid and it occurs in the liver
when deamination has occurred why is it important to covert ammonium into urea
because ammonia is highly acidic and it is a small molecule which needs to be quickly converted into a less toxic form for example urea
name the functions off the afferent arteriole efferent atriol glomerulus glomerus capsule proximal convoluted tubule the loop of henle the distal convoluted tubule and the collecting ducts
afferent arteriole carries high pressure blood to the arteriole
efferent arteriole carries bloods away from the glommerus
a knot off capillaries where blood is filtered off all substances besides from blood and proteins
glomerus capsule
surrounds the glomerulus and catches any glommerus filtrate
proximal convoluted tubule
the reabsorption off sodium, potassium, chloride, hydrogen, carbonate ions, glucose amino acid, vitiman c, water ( osmosis)
loop of Henle
the reabsorption of water through osmosis
distal convoluted tubule
reabsorption off sodium ions active reabsorbtion off water, secretion of hydrogen, potassium and ammonium ions certain and certine drugs
collecting ducts
active reabsorption off water depending on the bodies needs
what are the roles of the kidneys the ureters the bladder the bladder and the urethras
kidneys maintain the optimal concentration of the materials in the body fluid and remove metabolic wastes such as urea
ureters transport urine to the bladder
bladder stores urine before it is excreted
urethra transport’s urine from the body to the outside off the body
outline what occurs in the cortex medulla and and pelvis
cortex begins the filtration off blood for urine production
medulla
where reabsorption occurs
pelvis
receives urine formed by the pelvis
what metabolic waste are excreted by the lungs skin and kidneys and where does it originate
lungs: carbon dioxide and water is excreted and it originates from the cells waste products in aerobic respiration
skin: sweat urea and water are removed and it originates from the deamination of amino acids in the liver and the cells
kidney: the metabolic wastes removed are urine (urea) creatin and water and they originate from the blood stream
