new - paper 1

• What does amylase break down?

  Starch into glucose
• What does protease break down?

  proteins into amino acids
• What does lipase break down?

  Lipids into fatty acids and glycerol
• What colour does iodine turn if starch is present?

  From orange to black
• What colour does Benedict's solution turn in the presence of sugar (glucose)?

  from blue to brick red
• What colour does Biuret's reagent turn in the presence of protein?

  From blue to lilac
• What happens to cold ethanol when lipids are added?

  It turns cloudy
• What does the vena cava do?

  Returns deoxygenated blood to the heart (right atrium)
• What does the pulmonary artery do?

  Carries deoxygenated blood from the heart to the lungs.
• What does the pulmonary vein do?

  Carries oxygenated blood from the lungs to the heart.
• What does the aorta do?

  Carries oxygenated blood from the heart to the body.
• What are features of arteries?

  Thick walls and thin lumen to withstand pressure

  Carries blood away from the heart
• What are features of capillaries?

  Walls are one cell thick to allow quick diffusion between blood and cells
• What are features of veins?

  Thin walls and wide lumen

  Has valves to prevent backflow

  low pressure

  Carries blood back to the heart
• What are stents and statins?

  Stents can be inserted into a blood vessel to open it up if fatty deposits are blocking it

  Statins are drugs that reduce fatty deposits
• What do coronary arteries do?

  Supply blood to the heart.
• What is chlorosis and what does it do?

  It is a magnesium deficiency in plants that causes yellow leaves which stunts growth due to less chlorophyll
• What happens to plants with a nitrate ion deficiency?

  Nitrates are needed for protein synthesis and if a plant is deficient it will have stunted growth
• What are the different types of pathogen?

  Viruses - reproduce by inserting genes into cells, causing them to produce more copies (Measles, HIV)

  Bacteria - release toxins into the body that damage cells (Salmonella, gonorrhea)

  Fungi - damage cells

  Protists - single celled organisms (malaria)
• What is the fungal infection found in plants?

  Rose black spot - causes leaves to fall off

  Tobacco mosaic virus - discolours leaves, less chlorophyll, stunted growth
• What are lymphocytes?

  A type of WBC that produces antitoxins (to neutralise toxins made by pathogens) and antibodies (that bind to antigens of a pathogen).

  once the correct antibody is found for a specific pathogen, T cells store it in the lymph nodes
• What is a phagocyte?

  A type of WBC that ingest pathogens
• What is the equation for photosynthesis?

  Water + carbon dioxide --> glucose + oxygen

  6H2O + 6CO2 --> 6C6H12O6 + 6O2