Top answers

How can vaccination prevent illness?

Vaccination is a way of preparing the body's immune system to fight potential infection. By exposing the body to markers of the virus or bacteria, the white blood cells are able to recognise, memorise and fi...
GH
Answered by Gareth H. • Biology tutor
2953 Views

How does temperature affect enzymes?

Enzymes are proteins which catalyse (speed up without being used up) biological reactions. Each enzyme will only speed up one reaction as the shape of the enzyme molecule needs to match the shape of the mole...
LR
Answered by Liberty R. • Biology tutor
21783 Views

A student cut a piece of potato into 10 discs, each 1mm thick and with a 10mm diameter. He then placed them in a beaker of deionised water. After a couple of days, they had increased in size- both thickness and diameter. Explain why this is the case.

The cells composing the potato tissue contain fluid, or cytoplasm. This contains dissolved salts and these ions attract water molecules; cations, or positive ions, attract the partially negatively charged ox...
EK
Answered by Eva K. • Biology tutor
3486 Views

What is homeostasis?

Homeostasis is the maintenance of a constant internal environment in organisms despite external changes. Homeostasis ensures that cells within an environment are able to meet their needs and function appropr...
YB
Answered by Yinka B. • Biology tutor
4133 Views

What is the difference between a virus and a bacteria? What is an example of each?

A virus is non-living and cannot be treated by antibiotics, they do not have a cell wall. Viruses are generally smaller and require a host to survive. A bacteria can be affected by antibiotics and can surviv...
TR
Answered by Thomas R. • Biology tutor
17679 Views