Search over 10,000 free study notes

1. Alveoli in the mammalian lung are thin walled to allow the quick passage of gases, for example oxygen and carbon dioxide.

2. Alveoli in the mammalian lung have a large surface are...

A neurone is a special type of cell in the body which transmits electrical impulses.

Neurones can be classified into different types based on the information they receive and pass ...

Auxins are degraded within the tips of the shoots of the plant exposed to sunlight, and gather on the shaded side of the shoots. Gathered auxins enourage cell elongation, and the shoot to grow upwards, to...

When cells divide by cytokinesis the nucleus also has to divide so that each new cell contains a nucleus with a complete copy of all of the genetic information. DNA replication therefore needs to ensure t...

Firstly, the 'wave of excitation' is produced by the sinoatrial node (SAN) in the top of the right atrium - this is also known as the pacemaker, as this is what controls the rate of contractions. This wav...