1 / 15

Osmoregulation

hypotonic. Osmoregulation. Water balance vs. Habitat freshwater hypotonic to body fluids water flow into cells & salt loss saltwater hypertonic to body fluids water loss from cells land dry environment need to conserve water may also need to conserve salt. hypertonic.

qiana
Download Presentation

Osmoregulation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. hypotonic Osmoregulation • Water balance vs. Habitat • freshwater • hypotonic to body fluids • water flow into cells & salt loss • saltwater • hypertonic to body fluids • water loss from cells • land • dry environment • need to conserve water • may also need to conserve salt hypertonic Why do all land animals have to conserve water? • always lose water (breathing & waste) • may lose life while searching for water

  2. H O H | | | –C– C–OH N | H R Intracellular Waste • What waste products are made inside of cells? • what do we digest our food into… • proteins = CHON • nucleic acids = CHOPN lots! verylittle CO2 +H2O + N  CO2 +H2O + P + N CO2 + H2O NH2= ammonia

  3. Nitrogenous waste disposal • Ammonia (NH3) • very toxic • carcinogenic • very soluble • easily crosses membranes • must dilute it & get rid of it… fast! • How you get rid of nitrogenous wastes depends on • who you are (evolutionary relationship) • where you live (habitat) aquatic terrestrial terrestrial egg layer

  4. Nitrogen waste • Aquatic organisms • can afford to lose water • ammonia • most toxic • Terrestrial • need to conserve water • urea • less toxic • Terrestrial egglayers • need to conserve water • need to protectembryo in egg • uric acid • least toxic

  5. Freshwater animals • Hypotonic environment • water diffuses into cells • Manage water & waste together • remove surplus water & waste • use surplus water to dilute ammonia & excrete it • also diffuse ammonia continuously through gills • overcome loss of salts • reabsorb in kidneys or active transport across gills

  6. H H H H N N C O Land animals • Nitrogen waste disposal on land • need to conserve water • urea= larger molecule = less soluble = less toxic- produced in liver • kidney • filter solutes out of blood • reabsorb H2O (+ any useful solutes) • excrete waste • urine = urea, salts, excess sugar & H2O • urine is very concentrated • concentrated NH3 would be too toxic mammals

  7. Egg-laying land animals • Nitrogen waste disposal in egg • no place to get rid of waste in egg • need even less soluble molecule • uric acid = BIGGER = less soluble = less toxic • birds, reptiles, insects

  8. O O O N N N N H H H H Uric acid • Polymerized urea • large molecule • precipitates out of solution • doesn’t harm embryo in egg • white dust in egg • adults still excrete N waste as white paste • no liquid waste • uric acid = white bird “poop”!

  9. Mammalian System blood filtrate • Filter solutes out of blood & reabsorb H2O + desirable solutes • Key functions • filtration • fluids (water & solutes) filtered outof blood • reabsorption • selectively reabsorb (diffusion) needed water + solutes back to blood • secretion • pump out any other unwanted solutes to urine • excretion • expel concentrated urine (N waste + solutes + toxins) from body concentratedurine

  10. Nephron: Filtration • At glomerulus • filtered out of blood • H2O • glucose • salts / ions (Na+ / Cl–) • urea • not filtered out • cells • proteins high blood pressure in kidneysforce to push (filter) H2O & solutes out of blood vessel

  11. Nephron: Re-absorption • Proximal tubule • reabsorbed back into blood • NaCl • active transport of Na+ • Cl– follows by diffusion • H2O • glucose • HCO3- • bicarbonate • buffer for blood pH

  12. Nephron: Re-absorption • Loop of Henle • descending limb • reabsorbed • H2O • structure • many aquaporins in cell membranes • high permeability to H2O • no Na+ or Cl– channels • impermeableto salt

  13. Nephron: Re-absorption • Loop of Henle • ascending limb • reabsorbed • Na+ & Cl– • structure • many Na+ / Cl– channels in cell membranes • high permeability to Na+ & Cl– • no aquaporins • impermeable to H2O

  14. Nephron: Re-absorption • Distal tubule • reabsorbed • salts • H2O • bicarbonate • HCO3- • regulate blood pH

  15. Nephron: Reabsorption & Excretion • Collecting duct • reabsorbed • H2O = through aquaporins • excretion • concentrated urine • to bladder • impermeable lining = no channels in cell membranes

More Related