Prediction answers paper 1 bio

• Enzymes are biological catalysts that speed up chemical reactions without being used up .
• Prokaryotic cell do not have a nucleus
• Eukaryotic cell has nucleus are larger and a membrane bound organelles
• Sperm cells are specialised. They have a flagellum in order for the sperm cell to move and swim to the egg. The cell has acrosomes which contain digestive enzymes to penetrate the egg. They have a streamline head to help manoeuvre faster
• Mutation is a change in the sequence of DNA
• Mutations do not have negative effects because it increases chance of survival
• Embryonic stem cells can differentiate into any type of cell
• Embryonic stem cells could be used to treat currently untreatable diseases or growing new organs for transplant
• Adults stem cells can differentiate into specific specialised cells and fewer it has ethical challenges you are killing the embryo
• xylem transport, water and minerals up the plant the process is transcription
• Phloem transport sugar up and down the plant this process is translocation
• temperature affects the function of digestive enzyme as the higher the temperature the greater the rate of reaction of enzyme up to the optimum temperature
• If the optimum temperature goes higher the enzyme will denature and the substrate cannot bind the active site
• To test for sugar, use Benedict’s reagants the colour water blue to red
• The test for starch is iodine which goes from brown to blue/black
• The test for protein is biuret test which goes from blue to purple if protein is present
• To test for lipid and ethanol to the test tube, it will go from colourless to cloudy white if lipids are present
• Malaria is caused by protist
• Pathogen spread in direct contact ,bodily fluids,vectors and droplets
• How does vaccinations work?

  once in the bloodstream, the antigen contained within the vaccine can trigger an immune response. lymphocytes recognise the antigens in the bloodstream activated lymphocytes produce antibodies specific to the antigen encountered memory cells and antibodies subsequently remain circulate in the bloodstream.
• herd immunity means if a large population of the population of vaccine it is unlikely that an unvaccinated individual will get infected so the spread of disease is limited
• C6H12O6 + 6O2 —> 6CO2 + 6H20 - aerobic respiration
• Anaerobic respiration ?

  Glucose —> ethanol + carbon dioxide
• Antiretroviral can be used to treat HIV infection to prevent AIDs developing
• AIDS kill white blood cell and weak the immune system therefore white blood cell cannot kill bacteria as efficiently
• The small intestine is where the enzyme lipase usually work to carry out fat digestion
• How the human body prevents the entry of pathogens ?


  • skin acts as a barrier and secrete oils that repel pathogens and scabs form over cut
  • The eyes produce tears which contains enzymes to kill bacteria
  • The nose produces mucus which traps bacteria and the mucus is carried away by the cilia
• Genetic modification is A process of changing the structure of a particular gene, usually to remove defects
• Gene therapy is inserting working version of this genes into people with the genetic disease
• Genetic engineering steps ?

  • restriction enzymes are used to isolate the required enzyme leaving it was sticky and
  • A vector which is usually a bacterial plasma or virus is cut by the same restrictive enzyme leaving it with complimentary sticky end
  • the vector and the isolated gene are joined together by ligase enzyme
  • The vector inserts the gene into required cell
  • The Jesus transferred to () during early develop development which allows them to develop with the desired characteristics
• Advantages of genetic modification is can be used in future medicines
• Genetic engineering is faster and efficient way of getting the same resource as selected breeding
• Genetic engineering improves crop yield and crop quality introduces herbicides resistance
• Risks of genetic engineering crops could be harmful as resistant crops could pass on the gene to wild plants affecting food chain
• Risk of genetic engineering is not ethical to interfere with nature in this way
• Non communicable disease?


  smoking- tar and nicotine damage alveolI in the lungs and lining of the arteries and can cause lung cancer

  Alcohol- breakdown of alcohol in liver can produce substance that are toxic to liver cells leading to liver disease
• Lactic acid can be oxidised to form carbon dioxide and water