Water Balance

The balance and maintenance of various substances and molecules in the body in response to environmental changes

Mechanisms that maintain balance

Ideal range or middle point of the body

Water absorbs heat energy

When air is inhaled some of the moisture evaporates. This evaporated moisture can be used to cool the blood passing through the nasal cavity. This cooled blood is then passed between warm blood going to the brain. Countercurrent flow cools the warm blood.

the control of water flow by having water balance solute concentrations

ions in water

having the same concentration of ions inside cell and outside in the environment (jellyfish)

using homeostasis mechanisms to maintain a specific internal environment (terrestrial invertebrates and vertebrates)

The part of the membrane that faces the external environment

the part of the membrane that faces the inside of a cell

Sharks have the same osmolarity as the water they are in, but lower salt concentrations. To balance this in certain parts of their body that doesn’t need as much salt, they make urea. urea causes low salt concentration

3 sodium out and 2 potassium in. Changes the polarity of a membrane.

• Sodium-Potassium ATPase pumps 3 sodium out and 2 potassium in • Cotransporter brings the ions in like Cl- / Na+ / K+ • Cl- diffuses out to sea and k+ moves into body through diffusion • Na+ diffuses into lumen

Gain - Drinking and eatings Lose - urine, feces, breathing, and evaporation

Wax layer of the skin that prevents water loss

Ammonia, Uric acid, and Urea

Used to remove nitrogenous waste when lots of water is present and it is the easist to make

Used to remove nitrogenous waste, but needs lots of energy and does not need much water

Used tor remove nitrogenous waste and requires some energy, but it is harmless to the body

• Renal capsule • proximal tubule • Descending loop of henle • ascending loop of henle • Distal tube • collecting duct

Used for blood filtration in most terrestiral vertebrates

Pushes all filtrate out of the blood in the glomerulus due to the pressure of Bowman’s capsule

Tube of highly folded membrane that uses active transport to bring Na, glucose, Cl, and vitamins back into the blood