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Biology

A Level

Describe how antibiotic resistance occurs.

Firstly, antibiotic resistance has to be gained by a bacterium through the mutation of a gene. This can occur due to, for example, the overuse of antibiotics or failure to complete a full course of ant...

Answered by Anita H. • Biology tutor

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What are the differences between facilitated diffusion and active transport?

Facilitated diffusion doesn't require ATP whereas active transport does. This is because active transport involves the movement of particles against its concentration gradient, whereas facilitated diffusi...

Answered by Upasana T. • Biology tutor

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How would you explain oxidative phosphorylation and chemiosmosis?

Reduced coenzymes produced in the Krebs cycle; glycolysis and Link Reaction (Reduced NAD and FAD) carry Hydrogen ions and electrons to the inner mitochondrial membrane , within the membrane are a numbe...

Answered by Joseph B. • Biology tutor

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What are enzyme inhibitors?

Enzyme inhibitors function to slow down the rate of an enzyme catalysed reaction by interfering with the enzyme in some form. There are two main types of inhibitors:

Answered by Yasmin A. • Biology tutor

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What are the roles of the sinoatrial node (SAN) and the atrio-ventricular node (AVN)?

The heart muscle is myogenic and initiates a heartbeat through an electrical conduction system; both the sinoatrial node and atrio-ventricular node are essential in this mechanism.

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Answered by Shelby P. • Biology tutor

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