AS Physics Handwritten Notes 2015

AS Biology Handwritten Notes 2015

AS Chemistry Handwritten Notes 2015

AS level

From Note #1 to Note # 84 

#84 Question 7

Beetroot cells contain a red pigment that cannot normally escape from the cells through the cell surface membrane. A student carried out an investigation into the effect of temperature on the permeability of the cell surface membrane of beetroot cells.

#83 Question 6

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

#82 Question 5

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

#81 Question 4

The diagrams below show five molecules found in living organisms.

#80 Question 3

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

#79 Question 2

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

#78 Question 1

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

#77 Questions and answers

In this section is a practice examination paper, similar to the Cambridge International AS Level Biology paper 2. All of the questions are based on the topic areas described in the previous sections.

#76 Summary of Practical Skills

1 In an experiment investigating the effect of one variable on another, the independent variable is the one that you change and the dependent variable is the one that you measure. All other variables should be controlled (kept constant).

#75 Drawings

One of the questions in the exam is likely to involve drawing a specimen on a slide, using a microscope, or drawing from a photomicrograph (a photograph taking through a microscope).

#74 Identifying sources of error

It is very important to understand the difference between experimental errors and 'mistakes'. A mistake is something that you do incorrectly, such as misreading the scale on a thermometer, or taking a reading at the wrong time, or not emptying a graduated pipette fully. Do not refer to these types of mistake when you are asked to comment on experimental errors.

# 73 Drawing conclusions and interpreting data

Once you have collected, tabulated and displayed your results, you can use them to draw a conclusion. When you are thinking about a conclusion, look right back to the start of your experiment where you were told (or you decided) what you were to investigate.

# 72 Graphs and other ways of displaying data

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

#71 Recording measurements and other data

You will often need to construct a table in which to record your measurements, readings and other observations. It is always best to design and construct your results table before you begin your experiment, so that you can write your readings directly into it as you take them.

#70 Practical exam - Taking measurements

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

#69 How to get high marks in Paper 3 - Variables

Many of the experiments that you will do during your AS course, and usually Question 1 in the examination paper, will investigate the effect of one factor on another. These factors are called variables.