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Biology

A Level

What is the difference between DNA and RNA?

So, to start with what's the same, they are both molecules that are made from a nitrogenous base (Check understanding of term) and a sugar phosphate backbone. Now onto differences, DNA gets its name becau...

Answered by Rob P. • Biology tutor

2420 Views

Describe how reduced NADP and ATP is produced during the light-dependent stage of photosynthesis.

ATP is produced during both cyclic and non-cyclic photophosphorylation.During cyclic photophosphorylation, a photon of a wavelength 700nm hits a chlorophyll molecule in PS1 and excites a single electron. ...

Answered by Harison S. • Biology tutor

17228 Views

How is the liver adapted to regulating blood component concentrations?

Sinusoids are chambers within the liver where deoxygenated blood from the gut (containing products of digestion) and oxygenated blood from the heart, mix. Sinusoids are lined with liver cells (

Answered by Sana Z. • Biology tutor

3323 Views

Describe, using the fluid mosaic model, the structure of the cell membrane in animal cells.

The cell membrane is composed of phospholipid molecules. These have a hydrophobic head and a hydrophilic tail. The molecules arrange themselves in a bilayer so that the hydrophobic heads point outwards an...

Answered by Morgan G. • Biology tutor

2946 Views

Describe competitive and non-competitive enzyme inhibition

Competitive enzyme inhibition- the inhibitor compound is a similar structure to the enzyme’s active site. This means it can fit into the active site of the enzyme, via the glove induced fit, method creati...

Answered by Tom H. • Biology tutor

3806 Views