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The transmission of an action potential- the signal- from one neurone to another occurs over the synapse. The structure of a synapse is as follows; there is a presynaptic bulb, a post synaptic bulb and th...

Natural selection is when certain characteristic are 'selected' for. Each species have simiar characteristics but differences in genes means that their characteristics can vary for example individual bird...

Muscle contraction can be explained using the 'Sliding Filament Hypothesis'. Following nervous stimulation, a nerve impulse will be transmitted to a neuromuscular junction. This will cause a release of th...

Diffusion is the spreading out of particles of any substance in solution or of gas resulting in a net movement of an area of high concentration to an area of low concentration. Diffusion is key to the sur...

Invasive species can cause negative effects on biodiversity through out-competing native species, becoming a voracious top predator and killing most of the native animals/fauna (especially since if there ...