From Note #1 to Note # 84 

Beetroot cells contain a red pigment that cannot normally escape from the cells through the cell surface membrane. A student carried out an...

The diagram below shows pressure changes in the left atrium and left ventricle of the heart and the aorta during the cardiac cycle.

The diagram below shows a small part of a human lung as it appears through a microscope.

The diagrams below show five molecules found in living organisms.

(a) The diagrams show a cell in various stages ofthe mitotic cell cycle.

The diagram shows the bacterium Mycobacterium tuberculosis, which causes tuberculosis (TB).

(a) The diagram shows a small part of a cell, as seen using an electron microscope.

In this section is a practice examination paper, similar to the Cambridge International AS Level Biology paper 2. All of the questions ar...

1 In an experiment investigating the effect of one variable on another, the independent variable is the one that you change and the depen...

One of the questions in the exam is likely to involve drawing a specimen on a slide, using a microscope, or drawing from a photomicrograp...

It is very important to understand the difference between experimental errors and 'mistakes'. A mistake is something that you do ...

Once you have collected, tabulated and displayed your results, you can use them to draw a conclusion. When you are thinking about a concl...

When you have collected your data and completed your results table, you will generally want to display the data so that anyone looking at...

You will often need to construct a table in which to record your measurements, readings and other observations. It is always best to desi...

You will often be asked to take measurements or readings. In biology, these are most likely to be length, mass, time, temperature or volu...

Many of the experiments that you will do during your AS course, and usually Question 1 in the examination paper, will investigate the eff...