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Biology
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How and why are bacteria used in industry?

Bacteria are used in industry to produce enzymes and other proteins. Because they are prokaryotes and don't have a nucleus, every DNA plasmid that is taken up is translated. You just have to insert the pl...

NW
Answered by Niclas W. Biology tutor
3086 Views

Describe the basic principles of cell theory giving examples to support them

The cell is the smallest unit of life. Organelles cannot survive by themselves.Challenge to the theory: green algae - highly complex mono-nucleated cell that is up to 10cm. All cells come from pre-existin...

KV
1726 Views

What is the 'lock and key' hypothesis?

A reaction can only be catalysed (sped up) if an enzyme's active site matches the shape of its substrate molecules- the substrate fits into the active site like a key into a lock. This shape is highly spe...

EE
Answered by Emily E. Biology tutor
2563 Views

Explain the sliding filament model of skeletal muscle contraction

An action potential on a motor axon reaches the axon terminal, causing acetylcholine to be released. It diffuses across the neuromuscular cleft in synaptic vesicl...

MP
Answered by Maddie P. Biology tutor
1792 Views

Describe active transport

Active transport is the movement of a substance against its concentration gradient across a selectively permeable membrane. In order for an organism to carry out active transport energy is required to ove...

AH
Answered by Alexander H. Biology tutor
2572 Views

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