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Could you explain the difference between passive diffusion and facilitated transport?

Passive diffusion occurs without any transmembrane proteins being involved, the molecules cross the lipid bilayer following a concentration gradient (from the highest concentration to the lowest). Small unch...
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Answered by Eleonore W. • Biology tutor
4002 Views

How does the body regulate heat?

Body temperature is regulated by a thermoregulatory centre in the brain, the hypothalamus. The hypothalamus can sense the temperature of the blood via receptors. The skin also contains temperature receptors ...
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Answered by Natasha C. • Biology tutor
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If the concentration of testosterone in a man’s blood starts to rise above normal, this system leads to a reduction in testosterone. How does this occur?

Students are aware of the Hyothalamus-pituitary axis (HPA axis) in the female, but are not as aware about the role of the HPA axis in the male reproductive system. Here,we should start off by explaining the ...
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Answered by Thahesh T. • Biology tutor
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How is the process by which plants turn towards a light source called and what is the role of auxin (IAA) in it?

The process is called phototropism (‘photo’-light, ‘tropism’ – ‘tendency of an animal or plant to turn or move in response to a stimulus’). IAA (Indole Acetic Acid) is a plant hormone belonging to a class ca...
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Answered by Emiliya T. • Biology tutor
9142 Views

Name a substance that can be transported across a membrane by simple diffusion and explain why it is able to be transported by this method.

Oxygen is an example of a molecule that is able to move across a membrane via simple diffusion. It is able to do so as it is a non-polar, uncharged molecule. Thus, it is a lipophillic molecule which means th...
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Answered by Tamarind R. • Biology tutor
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