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Explain the characteristics of enzymes and the lock and key theory of enzyme action. Explain the role of enzymes in catabolic and anabolic reactions.

1) enzymes are biological catalysts that will speed up reactions by reducing activation energy for the reaction. 2) Lock and key theory concerns how the enzyme (lock) only forms a reactive complex with a spe...
JB
Answered by James B. • Biology tutor
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How does filtration through the kidney work?

There are 3 key stages in filtration through the Kidney: Firstly, blood is pushed through a tubular structure called the glomerulus - imagine a bowl of noodles. The pressure of the blood in the glomerulus ca...
AP
Answered by Alastair P. • Biology tutor
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Describe the changes at the cell membrane of a neuron during an action potential.

At rest the membrane potential is -70mV . This is due to the Na + /K + pump, which actively transports 3 Na + ions out of the cell for every 2 K + ions in. Therefore there is a net negative charge inside the...
AN
Answered by Alex N. • Biology tutor
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Outline the lock and key mechanism of enzyme-controlled reactions

Enzymes are proteins that catalyse specific biological reactions in the body. These proteins have a specific 3D structure known as a teritary structure, with a specialised domain known as an 'active site' th...
MJ
Answered by Michael J. • Biology tutor
7901 Views

Explain how skeletal muscle contraction is stimulated

A nerve impulse travelling down a motor neurone causes the release of acetylcholine from the synpatic knob into the synaptic cleft. This then diffuses across the synaptic cleft down its concentration gradien...
MJ
Answered by Michael J. • Biology tutor
4399 Views