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How do I answer a question asking me to describe and/or explain a graph?

These questions should be easy mark gainers as they don't usually require a lot of prior knowledge. However, many students find that they consistently lose all their marks on these questions. With many exam ...
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Answered by Kate B. • Biology tutor
21435 Views

Describe how the SAN and AVN control the cardiac cycle.

The student should think about this in steps starting with: 1. SAN initiates the heartbeat: The sinoatrial node (SAN) initates heart contraction by sending electrical impulses across the atria. These are ini...
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Answered by Elizabeth G. • Biology tutor
20925 Views

Describe the process of an action potential through a neuron

A stimulus (e.g. change in temperature, pain, etc.) results in the depolarisation of the membrane of the neuronal cell body. This depolarisation causes the membrane potential to rise from resting potential (...
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Answered by Emily C. • Biology tutor
5047 Views

What are the events that lead to synaptic transmission between two neurons?

There are three compartments to consider- the presynaptic neuron, the synaptic cleft and the postsynaptic neuron. In a classical excitatory synapse: 1. An action potential arrives at the presynaptic neuron, ...
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Answered by Holly H. • Biology tutor
3890 Views

Why is genetic diversity important within a population?

Genetic diversity within a population is the variety of different alleles (versions) of genes present, which lead to a variety of phenotypes. It is important for a number of reasons, such preventing inbreedi...
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Answered by Rosie S. • Biology tutor
10689 Views