Muscle Contraction – Muscles Ep 2

Muscle contraction is a tricky bit of A-Level biology. There are lots of new terms to learn and a complex process to get your head around. Make sure to review it regularly so that it sticks in your brain. Before beginning this article, make sure you are happy with the different parts of a muscle... Continue Reading →

Synapses – Nervous Communication Ep 5

We know that nerve impulses are carried along neurones in a wave of depolarisation. But how does a nerve impulse get transmitted from one neurone to the next? Well, that is where synapses come in. Structure of synapses Synapses are the microscopic gaps between neurones. The neurone before the synapse is called the presynaptic neurone,... Continue Reading →

Digestion – Exchange and Transport Ep 13

So far in the exchange and transport series we have mainly been looking at exchange and transport of gases. However, organisms also need to absorb nutrients such as glucose and amino acids so they can carry out processes like respiration and protein synthesis. In this article we will cover how large food molecules are broken... Continue Reading →

Active Transport – Exchange and Transport Ep 4

So far we have looked at the passive movement of substances across cell membranes by diffusion and osmosis. Sometimes substances need to move against a concentration gradient, which is when active transport comes into action. Active transport Active transport uses energy from ATP to transport substances from an area of low concentration to an area... Continue Reading →

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