190 likes | 234 Views
This text discusses the concepts of osmoregulation, thermoregulation, and nitrogenous waste disposal in organisms. It explores the challenges faced by osmoregulators living in freshwater and saltwater environments. The text also explains the different types of nitrogenous waste and their disposal mechanisms in aquatic and terrestrial organisms. Additionally, it covers the functions and structure of the mammalian kidney in blood filtration and urine concentration. The endocrine system's role in controlling blood osmolarity and pressure is also discussed.
E N D
Regulating the InternalEnvironment Water Balance & Nitrogenous Waste Removal
Conformers vs. Regulators • Two evolutionary paths for organisms • regulate internal environment • conform to external environment osmoregulation thermoregulation regulator regulator conformer conformer
Osmoregulation • A What are the challenges faced by an osmoregulator living in freshwater? • B What are the challenges faced by an osmoregulator living in the sea?
hypotonic Osmoregulation • Water balance • freshwater • hypotonic • water flow into cells & salt loss • saltwater • hypertonic • water loss from cells • Land • need to conserve water hypertonic
Nitrogenous waste disposal • Ammonia (NH3) • very toxic • very soluble • must dilute it & get rid of it aquatic terrestrial terrestrial egg layer
Nitrogen waste • Aquatic organisms • Ammonia • Terrestrial • urea • less toxic • Terrestrial egglayers • uric acid • least toxic
Mammalian System blood filtrate • Filter solutes out of blood & reabsorb H2O + desirable solutes • Key functions • Filtration • reabsorption • selectively reabsorb • secretion • pump out unwanted solutes • excretion • expel concentrated urine concentratedurine
Mammalian Kidney inferiorvena cava aorta adrenal gland kidney nephron ureter renal vein& artery epithelialcells bladder urethra
Mammalian kidney • Interaction of circulatory & excretory systems • Circulatory system • Glomerulus • Excretory system • nephron • Bowman’s capsule • Proximal tubule • loop of Henle • descending limb • ascending limb • Distal tubule • collecting duct Proximal tubule Distal tubule Bowman’s capsule Glomerulus Glucose H2O Na+ Cl- Amino acids H2O H2O Na+ Cl- H2O Mg++ Ca++ H2O H2O Collecting duct Loop of Henle
Nephron: Filtration • At glomerulus • filtered out of blood • H2O • glucose • salts / ions • urea • not filtered out • cells • proteins high blood pressure in kidneysforce to push (filter) H2O & solutes out of blood vessel
Descendinglimb Ascendinglimb Nephron: Re-absorption • Proximal tubule • reabsorbed back into blood • NaCl • active transport of Na+ • Cl– follows by diffusion • H2O • Glucose, amino acids • HCO3- • Bicarbonate (pH)
Descendinglimb Ascendinglimb Nephron: Re-absorption • Loop of Henle • descending limb • high permeability to H2O • many aquaporins • low permeability to salt • reabsorbed • H2O structure fitsfunction!
Descendinglimb Ascendinglimb Nephron: Re-absorption • Loop of Henle • ascending limb • low permeability to H2O • Cl- pump • Na+ follows by diffusion • reabsorbed • salts • maintains osmotic gradient structure fitsfunction!
Nephron: Re-absorption • Distal tubule • reabsorbed • salts • H2O • HCO3-
Descendinglimb Ascendinglimb Nephron: Reabsorption & Excretion • Collecting duct • reabsorbed • H2O • concentrated urine passed to bladder
Summary • Not filtered out • cells u proteins • remain in blood (too big) • Reabsorbed: active transport • Na+u amino acids • Cl–u glucose • Reabsorbed: diffusion • Na+u Cl– • H2O • Excreted • urea • excess H2O u excess solutes (glucose, salts) • toxins, drugs
increasethirst pituitary nephron high low Endocrine System Control Blood Osmolarity ADH increasedwaterreabsorption blood osmolarity ADH = AntiDiuretic Hormone
high low JGA adrenalgland nephron Endocrine System Control Blood Osmolarity/Blood Pressure JGA = JuxtaGlomerular Apparatus blood pressure increasedwater & saltreabsorption in kidney renin aldosterone angiotensinogen angiotensin
Don’t get batty… Ask Questions!!