New answers tagged physiology
0
Some mollusks have lungs and can use breath for nest building, defense and diving. They have 100 times less neurons than arthropods.
semi-aquatic insects can control air for going under-water, and some spiders, beetles and spittle-bugs can control bubbles. There are even shrimps that snap at water to produce bubbles.
Fish can hoover and squirt out targets ...
23
The argument that blood plasma resembles sea-water, in essence, relies on the notable similarity in concentration of two ions in plasma and sea-water, compared with their intracellular concentration: sodium and potassium.
The concentration of sodium-ion in sea-water is about 450 mM, whereas the concentration of potassium-ion is only about 10 mM (ref)
The ...
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Even shorter answer: This can be easily (well, not that easily since you need to convert mols to milligrams) answered by looking at your last lab result.
Say you had Na: 135 mmol/ml on there which would be a plausible value. That's 135*22.88/1000 mg/ml or 3.1 g/l. Sea water has around 19 g/l, so that's a clear, definite "no".
It wouldn't be quite such a ...
47
Short answer
Early sea water had a very different osmolality than blood plasma.
Background
The reference range of serum osmolality is 275–295 mosm/kg (mmol/kg) (MedScape). The osmolarity of sea water is about 1000 mOsm/l (Wikipedia), but it can vary substantially between different seas, namely between 642 and 1,480 mOsm/kg (Ninawe & Banik, 1998). ...
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