Osmoregulation

Osmoregulation is the process of maintaining [blank_start]water[blank_end] balance

Land based animals are able to retain water longer and more efficiently than water-based animals

- Water-based animals have plenty of available water and can dilute their nitrogenous waste easily. In this case, they produce [blank_start]ammonia.[blank_end] - Those that are land based but live near water produce [blank_start]urea.[blank_end] - Those that go long periods of time without water produce [blank_start]uric acid.[blank_end]

Water and solutes can all move into an out of an organism as a result of c[blank_start]oncentration[blank_end] g[blank_start]radients[blank_end]

- If the animal lives in the ocean they will have to deal with high levels of salt outside their body - which would create an osmotic gradient causing water to want to rush out of the body. - If the animal lives in fresh water they will have to deal with very low levels of solutes - which would create an osmotic gradient causing solutes to want to rush [blank_start]out of[blank_end] the body.

An osmo regulator is an organism who adapts the temperature of their external environment

An osmo conformer is an organism who adapts the temperature of their external environment

Osmo conformers conserve energy

Osmo regulators maintain a stable internal balance

- Osmo regulators must be able to get rid of (or take up) any excess [blank_start]salts[blank_end]. In humans, we get rid of excess salt via our [blank_start]urine[blank_end] and uptake more salt through [blank_start]eating and drinking.[blank_end] - Osmo regulators also use up a considerable amount of energy maintaining the osmotic gradient via [blank_start]active[blank_end] transport. If this didn't happen, water would come rushing out of the body and the organism would die quickly.

What adaptions do marine organisms make to regulate water levels?

Animals in freshwater are continually faced with water moving [blank_start]into[blank_end] their bodies (the water is hypotonic to their internal environment). As such, an impermeable barrier-like fish scales [blank_start]restricts[blank_end] water intake to permeable areas (thus reducing water gain and solute loss). Usually have a [blank_start]high[blank_end] uptake of salts through their gills in order to keep the necessary solute concentrations high inside the organism. Freshwater organisms have a very high [blank_start]kidney[blank_end] filtration rate and produce a large volume of of dilute urine. Due to the release of this volume of water, toxic [blank_start]ammonia[blank_end] can be safely washed from the body and no further energy is required to convert the ammonia to a less toxic form.

Terrestrial Organism Adaptions:

[blank_start]Waterproof Outer Surface:[blank_end] Skin, scales, or skeleton [blank_start]Reduction in Kidney Filtration Rate:[blank_end] Lower filtration rate causes less water loss. Kidneys also reabsorb a large amount of water from urine. [blank_start]Modification of Behaviour:[blank_end] Such as burrowing during the day and going into aestivation during drought (less heat, less water loss). [blank_start]Using Metabolic Waste[blank_end] Produced in Cellular Respiration: Water is released in cellular respiration more from fat than carbohydrates. Some animals store fat to produce more water this way. [blank_start]Tissues Tolerant to Water Loss:[blank_end] In the camel, for example, the fat stored in the hump allows a high level of production of metabolic water. The camel can survive long periods without water because its tissues can withstand higher levels of dehydration than other animals.

What is responsible for the reabsorption of water in mammals? [blank_start]ADH[blank_end]

What is the key component in the reabsorption of water in the kidney? [blank_start]The loop of henley[blank_end]

The smaller the loop of henley, the more water can be absorbed.

[blank_start]2.[blank_end] ADH will then travel via the blood to the [blank_start]kidney[blank_end] where it will stimulate the distil proximal tubes and collecting ducts of the nephron to become [blank_start]more[blank_end] permeable to water. The result of which is more water being absorbed from the urine and being kept in the body. [blank_start]4.[blank_end] In this way, a hormone, [blank_start]ADH[blank_end] controls the water balance in a mammal. [blank_start]3.[blank_end] Retaining this water helps to [blank_start]restore[blank_end] the balance of water within the organism. After which, the receptor cells in the hypothalamus will slow (or switch off) ADH production in the [blank_start]pituitary gland[blank_end]. [blank_start]1.[blank_end] When an animal has lost a lot of water, the amount of intercellular and extracellular fluid [blank_start]decreases[blank_end]. This also causes the animal to have low blood pressure. This drop in blood pressure is detected by cells in the hypothalamus which causes the pituitary gland to release ADH.