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Can you explain the oxygen dissociation curve? and the Bohr Shift?

As each O2 molecule binds to the haemoglobin, it alters the shape of the protein --> making subsequent binding more favourable. Therefore the affininity for oxygen will be greater in places with a higher ...
LB
Answered by Louis B. • Biology tutor
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I'm not sure how to answer the longer-answered questions e.g. those that are 6 marks.

This is a really common question that people ask actually and I struggled with this when I did GCSE. It's a good idea to jot down the points you want to include whilst you're learning how to answer these que...
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Answered by Laura B. • Biology tutor
3505 Views

Describe the process of ventilation, including the difference between active and passive expiration.

To expand the lungs and fill them with air, thoracic pressure decreases. This is done by the diaphragm contracting and flattening out and the external intercostal muscles raising the ribcage upwards and outw...
SG
Answered by Steph G. • Biology tutor
10684 Views

Describe how a synapse works to transmit a nervous impulse from one neuron to another neuron.

There is a pre-synaptic and post-synaptic neuron. An impulse stimulates the presynaptic neuron, travelling down to the synaptic bouton. This releases neurotransmitters into the synaptic cleft, which diffuse ...
SG
Answered by Steph G. • Biology tutor
3452 Views

Strains of the bacterium Staphylococcus aureus have developed which are resistant to several types of antibiotic. Scientists have named these strains MRSA. These strains have developed as a result of...?

The answer is natural selection. you have a colony of the bacterium and one bacterium develops a mutation which allows it to become resistant to some types of antibiotics. the bacteria that dont have the mut...
SS
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