Osmoregulation in FishFresh water (e.g. Trout) :
Osmoregulation in FishFresh water (e.g. Trout) ADAPTION: is a characteristic possessed by an organism that makes it better suited to it’s environment. Bony fish either live in fresh or sea water. Fresh water is hypotonic to the fish whereas sea water is hypertonic to the fish. HYPERTONIC Water is gained by osmosis Salts actively absorbed by chloride secretary cells Water is lost through large volume of urine which is dilute containing ammonia KIDNEY has:
High filtration rate
lots of large glomeruli
short tubules. The salt concentration of the fish is maintained by the CHLORIDE SECRETARY CELLS, replacing the salts lost by urination. It has to try and stop the body cells from swelling up due to the constant intake of water
Osmoregulation in fishSalt water (e.g. Tuna) :
Osmoregulation in fishSalt water (e.g. Tuna) Water is lost by osmosis, but drunk to compensate Hypotonic Sea water The drunk water is too salty so excess salt is secreted by the chloride secretary cells The water goes out of the kidney is a small amount and is concentrated (TMO) KIDNEY:
Has a low filtration rate
Few small glomeruli
longer tubules. Water concentration of the fish is maintained by the chloride secretary cells and the small amount of urine produced. It suffers dehydration of its cells as water is being lost to the surroundings
Adaptation of Migratory fishSalmon :
Adaptation of Migratory fishSalmon Salmon spend half their lives in Fresh water and half their lives in the sea.
The key role in allowing this to happen is ACCLIMATISING in the river estuary before breeding and feeding.
Slide 5:
Mammals
Desert rat :
Desert rat There are two types of adaptation:
Physiological
Behavioural Physiological
mouth and nasal passages dry
does not produce sweat
High level of ADH produced
Long kidney Tubules
produces very dry faeces. Reduced water loss Increases water retention Behavioural
Nocturnal Keeps cool