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How do internal stimuli affect a positive and a negative feedback loop?

Deviation from homeostasis causes the activation of feedback loops in order to restore equilibrium to the organism. An example of a negative feedback loop is the homeostasis of blood glucose; the increase in...
AK
Answered by Alexia K. • Biology tutor
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What is an easy way to pick up marks in the biology GCSE?

Biology GCSE like any other requires a basic level of understanding, but in addition it requires you to use scientific terminology. By using specific words or descriptions in your answers you make it easier ...
EC
Answered by Eleanor C. • Biology tutor
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How do white blood cells defend against invading pathogens?

They can engulf and ingest pathogens; this is essentially the white blood 'eats' the pathogen. They secrete (release) antitoxins which counteract the toxins released by pathogens. The toxins they release are...
EM
Answered by Emily M. • Biology tutor
15387 Views

What is another model for enzyme activity?

Another proposed model is induced fit. This suggests that the substrate and active site are not a perfect match to each other. So inorder to fit together both the substrate and active site must change shape ...
EM
Answered by Emily M. • Biology tutor
4652 Views

What is a proposed model for enzyme activity?

The lock and key model: Only substrates of a specific shape that is complementary to the active site of an enzyme can fit into the active site, in a way that is analagous to a key fitting into a lock.
AP
Answered by Alastair P. • Biology tutor
5387 Views