You are a neuroscientist and have been provided a sample of a new snake venom. You test its effect on action at a synapse, and find that it increases the magnitude of the normal depolarizing excitatory response. The most likely explanation for this is that the venom is: O O O preventing the presynaptic action potential from arriving at the synapse. degrading the myelin sheath around the axon. acting to break down the neurotransmitter in the synaptic cleft. reducing the distance between neighbouring neurons. binding with the neurotransmitter receptors to interfere with neurotransmitter binding. blocking the release of the neurotransmitter from the vesicles. binding with the neurotransmitter receptors to mimic the action of the neurotransmitter. binding to hormone receptors and stimulating the release of androgens

1. Mr and Mrs Burdesha are planning to start a family. However, Mr Burdesha is concerned that, as his brother was diagnosed with Colour blindness, he may be a carrier. Their GP explains how Mr Burdesha may carry the faulty gene for colour blindness using a Punnett square. Using Cc to represent a carrier, create a Punnett square using the template below to explain to Mr Burdesha his chances of inheriting the gene from his parents if both of them were carriers of colour blindness. Explain your answer in terms of gamete formation and fertilisation:

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3. Why do women get more tooth problems during pregnancy?