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Biology

A Level

How does the structure of DNA make it an effective carrier of genetic information?

DNA is a very long molecule (one cell contains about 2 metres of DNA!), meaning its coiled structure around proteins called histones allows it to fit into the small space of the nucleus. It also ...

Answered by Charlotte C. • Biology tutor

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How does acetylcholine transmit the nervous impulse across a synapse?

An action potential from the axon arrives at the presynaptic neuron, stimulating voltage-gated calcium (Ca²⁺) ion channels to open. This allows calcium ions to diffuse into the synaptic knob, c...

Answered by Charlotte C. • Biology tutor

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What is the structure of DNA?

DNA (DeoxyriboNucleic Acid) is a polymer (a molecule made up of many repeated subunits which form a chain). The subunit of DNA is a DNA nucleotide.

Answered by Hannah T. • Biology tutor

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What happens in the light independent reactions of photosynthesis?

The light-dependent reactions (LDR) take place in the stroma. It is also referred to as the Calvin Cycle.

CO2 and RUBP combine, using the enzyme RUBISCO. This forms an unstable 6C carbon-...

Answered by Tzeamara G. • Biology tutor

15516 Views

What is the difference between mRNA and tRNA?

RNA stands for riboncleic acid. mRNA is messenger RNA. This type of RNA is a linear polymer involed in a part of protein symthesis called transcription. It allows the DNA code to be taken outside the n...

Answered by Sophia L. • Biology tutor

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