Osmosis is the diffusion of water from a dilute solution to a more concentrated solution through a partially permeable membrane. In some people heart valves may become faulty, preventing the valve from opening fully, or the heart valve might develop a leak.
Understanding energy changes that accompany chemical reactions is important for this process. Malaria causes recurrent episodes of fever and can be fatal. Knowledge of ions is limited to nitrate ions needed for protein synthesis and therefore growth and magnesium ions needed to make chlorophyll.
Make estimates of the results of simple calculations. See also Enzymes and Biotechnology gcse chemistry notes You should be able to recall the sites of production and the action of the enzymes amylase, proteases and lipases.
Platelets are fragments of cells which initiate the clotting process at wound sites. You need to be able to describe the structure and function of these six cell types.
They frequently produce toxins that damage tissues and make us feel ill. Be able to discuss and explain the human and financial cost of these non-communicable diseases to an individual, a local community, a nation or globally.
The antibodies are specific to one binding site on one protein antigen and so are able to target a specific chemical or specific cells in the body. The spread of diseases can be reduced or prevented by eg simple hygiene measures, destroying vectors, isolation of infected individuals and vaccination.
Appreciate the need and use of an artificial heart, valve replacement, artificial blood e. The malarial protist has a life cycle that includes the mosquito.
Know that the roots, stem and leaves form a plant organ system for transport of substances around the plant. White blood cells help to defend against pathogens by: Monoclonal antibodies create more side effects than expected.
Rare species can be cloned to protect from extinction. The effect of alcohol on the liver and brain function. Translate information between graphical and numeric form. Phloem is composed of tubes of elongated cells. Benign tumours are growths of abnormal cells which are contained in one area, usually within a membrane.
Chemistry Paper 4, Topic 13 "The rate and extent of chemical change" 6. This process will supply energy but also causes the build-up of lactic acid in muscles which causes fatigue.
You should appreciate the differences in magnification and resolution between a light microscope and an electron microscope. In the case of heart failure a donor heart, or heart and lungs can be transplanted. HIV is spread by sexual contact or exchange of body fluids such as blood which occurs when drug users share needles.
Viruses living in cells can be the trigger for cancers. HIV initially causes a flu-like illness. Pathogens are microorganisms that cause infectious disease.
You should be able to use other models to explain enzyme action.Here is a selection of past papers organised by age group, subject, school and year.
There is also a list of other sources at the foot of the page: KS1 SATs KS1 SATs English Spelling Test - Playtime (QCA, ) KS1 SATs English Spelling Test - Making Soup (QCA, ) KS1 SATs English - Sunflowers.
Here are all the AQA Past Question Papers and Mark Schemes, sorted by subjects that we have available for polkadottrail.com of AQA GCSE past papers and AQA A-Level papers are displayed below. After you click on the subject you will be taken to the subject’s page where all the papers available for that subject will be displayed.
AQA GCSE Business Subjects and economics () exam past papers and marking schemes. Download them for free here. Preparing for exams Visit polkadottrail.com for everything you need to prepare for our exams, including: • past papers, mark schemes and examiners’ reports.
Our easy-to-use past paper search gives you instant access to a large library of past exam papers and mark GCSE; Functional Skills; Apprenticeships; International GCSEs and Edexcel Certs students can still get access to a large library of available exams materials. Try the easy-to-use past papers search below.
Learn more about past.
Search for past GCSE and A Level exam papers and mark schemes at Get Revising.Download