excretion in humans Flashcards
what substances do lungs excrete
-carbon dioxide and water vapour
-both formed as a product of cellular respiration
what substances do kidneys and bladder excrete
-urine
-urine was formed by kidneys
what does urine consist of
-water, mineral salts and waste= urea and uric acid
what’s urea
-formed in the liver from deamination of excess of amino acids
-urea is transported by blood to the kidneys
what’s urea
-formed in the liver from deamination of excess of amino acids
-urea is transported by blood to the kidneys
what’s uric acid
-end product of metabolism of nucleic acid
what substances does the liver excrete
-bile pigments and urea
what substances does the liver excrete
-bile pigments and urea
what are bile pigments
-formed in the liver during breakdown of haemoglobin
what substances do alimentary canal excrete
bile pigments
what substances do skin excrete
-sweat
what does the urinary system consist of
-two kidneys
-two ureters
-one bladder
-one urethra
what’s the function of the urinary system
-removed nitrogenous waste from blood stream and regulates water (osmoregulation), salt content and ph of blood
what does the renal vein do
-transports deoxygenated blood with waste products out of the kidney
what’s the function of the renal cortex
-surrounds renal medulla
-blood is filtered here
what’s the function of the renal medulla
-inner part of the kidney
-urines collected here
what’s the function of the nephron
-responsible for filtration
-more than 1 million per kidney
-tubular structured that extend from the cortex into medulla
what’s the function of the Malpighian body
-starting point of each nephron
-where blood filtration begins
what’s the function of the convoluted tubule
-follows malpighian body
-site of reabsorption of useful substances into the blood via peritubular capillaries
what’s the function of collecting ducts
-end of each nephron, directs urine to renal pelvis
how is urine formed
-filtrate contains waste and excess substances
what’s the function of glomerular filtration (ultrafiltration)
-blood enters glomerulus under high pressure due to narrower efferent arteriole
what’s tubular reabsorption
-occurs in proximal convoluted tubule
what’s tubular excretion
-tubule cells also excrete wastes from the peritubular capillaries into tubules
-this requires ATP
