How does excretion take place in plants?Describe the role of the human skin in homeostasis.

      

How does excretion take place in plants?Describe the role of the human skin in homeostasis.

  

Answers


Belinda

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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