Chpt. 44 Osmoregulation & Excretion Julianna Diddle Ethan Coombes

What is an osmoconformer? Where is homeostasis regulated in mamals vs. reptiles? What is an osmoconformer? What is an osmoregulator? Regulated internally = MAMMALS --Regulated externally = REPTILES -An animal that doesn’t actively adjust its internal osmolarity An animal that must control its internal osmolarity because its body fluids are not isoosmotic with the outside environment

-hyperosmotic -ioosmotic -hypoosmotic -saltwater -freshwater

What special characteristics do anhydrobiotic animals have? They can lose almost all body water & survive in a dormant state if their habitats dry up.

What are the three types of nitrogenous waste, what is different about them, and what is an animal that excretes each type? Ammonia(NH3) -most toxic -Excreted by aquatic animals Urea -low toxicity -Requires less water to dilute & can store large quantities -Mamals, adult amphibians, sharks, some bony fish, & turtles --Uric Acid -Least toxic -Insoluble -Can be excreted with little water loss but energetically expensive -Insects, land snails, many reptiles, & birds

What are the four main steps of the excretory process? 1. Filtration 2. Reabsorption 3. Secretion 4. Excretion

Kidney Renal Artery Renal vein Ureters Urinary Bladder Urethra

What is the pathway of filtrate after leaving the glomerular capsule? What is the functional unit of the kidney? (1,000,000/kidney in humans) What is the pathway of filtrate after leaving the glomerular capsule? What are the two types of nephrons? Nephron Proximal tubule, loop of Henle (descending & ascending loops), distal tubule, collecting duct, renal pelvis, ureter 1.) Juxtamedullary Extend into medulla, important for water conservation 2.) Cortical Loop of Henle stays in the cortex

What is the pathway for blood supplying each nephron? Systems that expend energy to create concentration gradients are –. Afferent arteriole, glomerular capillaries, Efferent arteriole, peritubular capillaries, vasa recta Countercurrent multiplier systems

What is the condition of increased urination called? What is the hormone that regulates water balance & increases collecting duct permeability to water What is the condition of increased urination called? Antidiuretic Hormone (ADH) -Diuresis

What does the RAAS do? (Renin-Angiostentin-Aldosterone System) What is the peptide hormone that opposes RAAS & is released by the atria of the heart in response to increased blood volume & pressure? -Works with the Juxtaglomerular apparatus (JGA) to drop blood pressure & blood volume & triggers JGA to release renin -Angiostentin II & Aldosterone reduce renin secretion in response to JGA Atrial Natriuretic Factor (ANF)

What is osmoregulation? What is excretion? Solute balance & gain or loss of water -Elimination of nitrogenous wastes