Biology - Excretion Flashcards
what is the difference between excretion and elimination?
excretion is the removable of metabolic waste and elimination is the removal of indigestible materials
what are the metabolic products of aerobic respiration?
carbon dioxide and water
what are the metabolic products of deamination in the liver?
urea, ammonia (nitrogenous waste)
how do water soluble waste get excreted in protozoans and cnidarians?
simple diffusion through the cell membrane
how do paramecium (a type of protozoa) maintain their volume and pressure?
contractile vacuole excretes water that is pumped in from the freshwater environment with energy
how is carbon dioxide excreted from annelids?
through the skin
what is a nephridia in an annelid?
excretes water, salt, urea
how is carbon dioxide excreted from arthropods/insects?
it transports to trachea which connect to external environments via spiracles
what are nitrogenous waste products excreted as in arthropods? why?
uric acid crystals; it conserves water
what do the lungs excrete in humans?
carbon dioxide and water vapor; they are pumped from the blood into the alveoli to be excreted with exhalation
what does the skin excrete?
water, salt and urea (small amounts)
what does the liver excrete?
nitrogenous waste, blood pigments and chemicals
what is the main area that excretes urea?
kidney
what part of the body maintains osmolarity of blood?
kidney
what does the kidney regulate?
the water and salt concentration of the blood
3 areas of the kidney:
outer cortex, inner medulla and renal pelvis
what the the Bowman’s capsule? what does it contain?
it contains a glomerulus; bowman’s capsule leads into the different loops and tubes of the kidney
4 functional units of the kidney?
proximal convoluted tubule, loop of Henle, distal convoluted tubule, collecting duct
what part of the nephron does the loop of henle run through?
the medulla
what part of the nephron do the convoluted tubules and Bowman’s capsule run through?
the cortex
what surrounds the nephron?
the peritubular capillary network
how much of the blood plans in the glomerulus is forced through the capillary walls and into the Bowman’s capsule?
20%
is the filtrate in the nephron isotonic, hypertonic or hypotonic to the blood plasma?
isotonic
what drives the process of filtration in urine formation?
hydrostatic pressure of blood
t or f? the nephron secretes harmful substances like K+, phosphate, acids and bases from the interstitial fluid into the filtrate via active and passive transport?
True
what is reabsorbed from the filtrate into the blood during urine formation?
glucose, salt, amino acid and water
what does reabsorption take place during urine formation?
proximal convoluted tubule
is reabsorption active or passive?
active
is the urine isotonic, hypertonic or hypotonic to the blood?
hypertonic
does tissue osmolarity increase or decrease from cortex to medulla?
increase
what is the countercurrent-multiplier system?
is allows for the most concentrated urine to be formed
is the medulla of the kidney hyperosmolar or hypoosmoolar to the filtrate in the collecting tube?
hyperosmolar
how does water flow out of the collecting tubules?
osmosis
what hormone regulates the permeability of the collecting tubules?
ADH (vasopressin)
does the presence of ADH increase or decrease the concentration of urine?
increases (allow for more water to be reabsorbed)
how do plants get rid of water vapor?
transpiration from stomates
how are carbon dioxide and water diffused out of plants?
diffusion through stomates and lenticels
