BISC 101 Lecture Notes - Lecture 16: Osmoregulation, Active Transport, Organism
16 Jun 2016
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Document Summary
Marine water, freshwaters and terrestrial habitats all have challenges for osmo/ionoregulation. Especially for terrestrial animals water balance is the main challenge. Aquatic animals have specialized epithelial cells to pump ions in/out depending on habitat via active transport. Osmoregulation: balances uptake and loss of water and solutes (homeostasis) Excretion: removal of excess solutes, nitrogenous wastes, metabolites, etc. Electrolytes: ions na ions, cl ions, k ions and ca ions. Some animals can resist the need of water. ***water moves by osmosis vs. water moves by active transport. Osmoconformer: organisms that conform their internal osmotic/solute environment according to their external environment. *** draw osmoconformer/osmoregulator graph from p. 3 on slides. Issue: environment you live in determine the challenges you must face with. Organism bodies are hypoosmotic in seawater: 300 <<<<<< 1000 mosm/l, osmotic stress for marine fish. Organism bodies are hyperosmotic in freshwater: 300 >>>>>> 1 mosm/l. Marine fish lose water by osmosis since sea water is high in solutes.
