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Diffusion of Carbon (IV) Oxide; and oxygen; through stomata and lenticels;
Some wastes are stored in tissues in non-toxic form e.g. calcium oxalate;
Some of these tissues or organs drop off from plants e.g. leaves, flowers, fruits and bark of caffeine, nicotine, quinine;
Some wastes are released by transpiration through stomata and lenticels such as water vapour;
Others are released by guttation through hydathodes as water;
Others are released by exudation.
When body temperature is lowered below normal;
arterioles in the skin constrict;
blood is diverted to a shunt system;
less blood flows to the skin/less heat is lost;
when body temperature is raised above normal;
arterioles in the skin dilate;
more blood flows to the skin;
more heat is lost by convection and radiation;
when body temperature is lowered below normal:
erector-pilli muscles contract, hair stands erect;
more air is trapped, air is a bad conductor;
and insulates the body against heat loss;
when body temperature is raised above normal:
erector-pilli muscles relax, hair lies on skin;
less air is trapped, more heat is lost;
when body temperature is lowered below normal:
less fluids are absorbed by sweat glands;
less sweating, less vaporisation of water;
when body temperature is raised above normal:
sweat glands are more stimulated and more sweat is produced;
water in sweat evaporates and takes up heat from the body;
body is cooled/body temperature is lowered;
adhixbelly answered the question on September 20, 2017 at 09:48
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