Search over 10,000 free study notes

All stem cells contain the same genes, but not all of these genes are expressed. Signalling causes certain genes to become activated within a stem cell. Only these activated genes are transcribed into mRN...

Normal neuronal resting potential is around -70mV - this is maintained by sodium-potassium pumps. When the neuron is stimulated, sodium ion channels begin to open, allowing sodium ions to diffuse back int...

The decrease in chlorophyll in the diseased plant leaves means the light energy cannot be used to make glucose via photosynthesis in the chloroplasts. Tomatoes store a lot of glucose therefore with less g...

ATP binds to the myosin head   Hydrolysis of ATP causes the head to come to a “cocked” position. Then the head binds to the actin binding site creating a cross-bridge ADP and Pi are released from the myos...

A reflex arc is a system of sensory, motor and relay neurones that work together to provide a quick reaction to stimulus that protects us from danger. A really good example that often comes up in t...