Practise IB Biology HL A1.1.3 by explaining how polarity and hydrogen bonding produce cohesion, surface tension and water transport in living organisms.
Water has unique properties and is needed by all living organisms to survive. Without water, life on Earth as we know it would not exist.
Outline how the cohesive properties of water benefit living organisms.
a. cohesion is caused by the polarity of water
OR
water molecules have a negative and positive end;
b. water molecules are attracted to each other
OR
water molecules are linked by hydrogen bonds;
c. (cohesion) enables transport of water along stems/xylem
OR
enables a continuous column of water in transpiration/transpiration pull;
d. surface tension provides a habitat for some organisms
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some insects can walk on water surface because surface tension/other verified example
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cohesion is related to buoyancy allowing organisms (like ringed seal) to float;
e. helps animals regulate body temperature (through evaporative cooling);
f. (cohesion causes high specific heat) so maintains a stable temperature in aquatic environments
OR
water is liquid at a wide range of temperatures supporting many aquatic habitats;
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