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During the light-independent reaction of photosynthesis, carbon dioxide is converted into organic substances. Describe how. (6marks)

Carbon dioxide from the atmosphere diffuses into the leaf through stomata and reaches stroma of chloroplast. In stroma, carbon dioxide combines with ribulose biphosphate (RuBP) in the presence of an enzyme c...
MC
Answered by Meral C. • Biology tutor
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Explain how partial pressure of oxygen affects how oxygen binds to haemoglobin in different areas of the body.

In the lungs, the partial pressure of oxygen is high therefore haemoglobin readily binds to the oxygen. This causes the haemoglobin to undergo a conformational change and increase its affinity for oxygen so ...
VA
Answered by Vinisha A. • Biology tutor
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Describe what happens when an action potential reaches an axon terminal.

When an action potential reaches an axon terminal, the depolarisation from causes voltage-gated calcium ion channels in the plasma membrane of the synaptic knob to open. As there is a much higher concentrati...
SJ
Answered by Sian J. • Biology tutor
14622 Views

What are the four bases found in DNA and how do they bond.

There are four DNA bases, Adenine (A), Cytosine (C), Guanine (G) and Thymine (T). On each strand of DNA, the DNA bases are connected by phosphodiester bonds, to form a long chain. These long DNA strands are ...
TJ
Answered by Toby J. • Biology tutor
19230 Views

How do I get full marks for this question "Describe how a vaccination leads to antibody production" ?

Mark 1: What is a vaccine? A vaccine contains antigens from an inactive form of a specific pathogen. Mark 2: Which cells are first to respond to the antigen? Antigen presenting cells such as macrophages pres...
CT
Answered by Chloe T. • Biology tutor
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