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Explain the function of the heart

The heart functions as a pump, circulating blood around the body to the cells. This is the medium for oxygen being delivered to the cells. The heart has two sides, left and right. Each one contains a ventric...
JC
Answered by Jacob C. Biology tutor
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Can you explain the pathway of a reflex arc/pathway?

Normally, whenever we smell/touch/see/hear/taste anything, that information gets sent to our brain and is processed before the brain decides whether we need to respond to the information. However, in situati...
SD
Answered by Soha D. Biology tutor
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Explain the process of speciation

Geographic isolation occurs so the population is separated and the two groups cannot interbreed. Variation due to mutation arises in the separate populations leading to different alleles becoming dominant an...
MW
Answered by Maria W. Biology tutor
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Why does an action potential not flow backwards in a neuron? How does it always reach the pre-synaptic knob?

When an action potential occurs, the neuron reaches the maximum voltage of +40mV. It then begins to repolarise, with potassium ions diffusing back in to the neuron, down the concentration gradient. This make...
EM
Answered by Erin M. Biology tutor
13648 Views

Describe the loading and unloading of oxygen by Haemoglobin in red blood vessels

Haemoglobin is a protein consisting of four haem groups contained in four polypeptide chains. The loading of oxygen consists of oxygen binding to iron in the haem group at areas of higher oxygen concentratio...
Answered by Biology tutor
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