Top answers

What is an allergy?

Allergy is the result of the immune system overreacting to harmless stimuli in the environment. Examples of stimuli or 'allergens' include pollen, dust, eggs and milk. The body recognises these harmless alle...
SK
Answered by Saadiyah K. • Biology tutor
5054 Views

How does filtration through the kidney work?

There are 3 key stages in filtration through the Kidney: Firstly, blood is pushed through a tubular structure called the glomerulus - imagine a bowl of noodles. The pressure of the blood in the glomerulus ca...
AP
Answered by Alastair P. • Biology tutor
4222 Views

Describe the changes at the cell membrane of a neuron during an action potential.

At rest the membrane potential is -70mV . This is due to the Na + /K + pump, which actively transports 3 Na + ions out of the cell for every 2 K + ions in. Therefore there is a net negative charge inside the...
AN
Answered by Alex N. • Biology tutor
11817 Views

Explain how skeletal muscle contraction is stimulated

A nerve impulse travelling down a motor neurone causes the release of acetylcholine from the synpatic knob into the synaptic cleft. This then diffuses across the synaptic cleft down its concentration gradien...
MJ
Answered by Michael J. • Biology tutor
4260 Views

Q: Describe the structure of an amino acid and the formation of a peptide bond.

Proteins are made up of organic molecules called amino acids . There are thousands of different proteins with diverse functions: storage, transport, structural support, cellular communication, enzymes and ho...
FM
Answered by Florence M. • Biology tutor
23992 Views