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What are the model structures associated with enzyme action?

There are two different models theorized by scientists in order to explain the performance of enzymes that you need to know about. The first is known as the 'Lock and Key hypothesis' where in the enzyme is a...
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Explain the transmission of nerve impulses across a cholinergic synapse

When an action potential arrives at the pre-synaptic neurone, it causes a change in voltage due to the presence of positive Na ions. This causes voltage-gated Ca 2+ protein channels to open and allow calcium...
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Answered by Kimran S. • Biology tutor
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Describe the structure and function of the cytoskeleton

An organelle found in all eukaryotic cells made of thin microfilaments of the protein actin and microtubules made of the protein tubulin. Transport is the key role where motor proteins drag organelles from o...
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Answered by Sakina L. • Biology tutor
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Explain how guard cells are specialised for their specific function

Guard cells open and close the stomata in a leaf. When the plant has lots of water the guard cells fill with it and become plump and turgid. This makes the stomata open so gases can be exchanged for photosyn...
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Answered by Grace K. • Biology tutor
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What is the maximum resolution for a standard optical microscope?

200nm
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Answered by Sakina L. • Biology tutor
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