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Biology

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How do cholinergic synapses communicate with each other (5)

Acetycholine released from presynaptic neurone2) Acetylcholine diffuses down its concentration gradient and attaches to receptors on postsynaptic neurones3) This causes sodium channels to open on th...

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Measles, mumps and rubella (MMR) are dangerous diseases that can be fatal to children. The MMR vaccine is given to children at a young age to produce antibodies against these diseases. Describe how giving the vaccine leads to the production of antibodies.

The vaccine contains weakened or dead antigens (from MMR). These antigens are displayed on antigen-presenting cells which are detected by a specific helper T cell. This stimulates a specific B cell which ...

Answered by Gracie B. • Biology tutor

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What is transpiration and what factors affect its rate of occurrence? Describe some adaptations of xerophytic plant that reduce water loss via transpiration.

Transpiration is the evaporation of water through open stomata, occurring down the water potential gradient.Factors affecting the rate of transpiration:Light intensity - more stomata will be open to take ...

Answered by Jessica T. • Biology tutor

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How is blood filtrated by the glomeruli in the kidneys?

Blood enters the glomerulus from the afferent arteriole at a very high pressure, so the hydrostatic pressure forces the contents of the blood out of the blood vessels, into the Bowman's capsule. However, ...

Answered by Joshua R. • Biology tutor

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(i) What is the net agin of ATP in Glycolysis? (2 marks) (ii) Where is ATP used in Glycolysis?( 1marks)

(i) In the breakdown of glucose 4 ATP is produced, however 2 ATP are used leaving a net gain of 2 ATP.(ii) In the energy investment stage, 2 ATP molecules are used to phosphorylate glucose into fructose d...

Answered by Sofia P. • Biology tutor

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