BIOLOGY PAPER 1

    Cards (73)

    • Microscopes
      Normal light microscope can see cells and nucleus, electron microscope can see subcellular structures in more detail
    • Magnification
      Image size / Object size
    • Cell types
      • Eukaryotic cells (have nucleus)
      • Prokaryotic cells (no nucleus)
    • Eukaryotic cells
      • DNA is found in the nucleus
      • Examples: plant and animal cells
    • Prokaryotic cells
      • DNA is found in a ring called a plasmid
      • No nucleus
    • Cell structures
      • Cell membrane
      • Cell wall (plant cells and bacteria)
      • Cytoplasm
      • Mitochondria
      • Ribosomes
      • Chloroplasts (plant cells)
    • Bacteria multiply by binary fission, doubling in number every 10 minutes
    • Bacterial culture growth
      1. Prepare agar dish using aseptic technique
      2. Incubate at 25°C
      3. Measure culture size or area of inhibition around antibiotics
    • Diploid cells
      Cells with 23 pairs of chromosomes (e.g. human body cells)
    • Haploid cells
      Cells with 23 single chromosomes (e.g. gametes)
    • Mitosis
      1. Genetic material duplicated
      2. Nucleus breaks down
      3. Chromosomes pulled to opposite sides
      4. New nuclei form in daughter cells
    • Cell specialisation
      • Cells specialize to perform specific functions (e.g. nerve, muscle, root hair cells)
    • Stem cells
      Unspecialized cells that can develop into different cell types
    • Diffusion
      Movement of molecules/particles from high to low concentration, no energy required
    • Osmosis
      Diffusion of water across a semi-permeable membrane
    • Osmosis experiment

      Cut potato cylinders, weigh, place in sugar solutions, reweigh, calculate % change in mass
    • Active transport
      Movement of substances against a concentration gradient, using energy
    • Tissues
      • Heart tissue
      • Digestive tissue
    • Organs
      • Heart
      • Liver
      • Stomach
      • Small intestine
    • Organ systems
      • Circulatory system
      • Digestive system
    • Enzymes
      Biological catalysts that break down specific molecules (e.g. amylase breaks down starch)
    • Enzyme active site
      Specific shape that allows substrate to bind
    • Enzyme activity
      Increases with temperature until active site is denatured
    • Enzyme activity
      Affected by pH, optimum pH where activity is highest
    • Enzyme activity experiment
      Mix enzyme and substrate, test for product formation at different temperatures or pH
    • Food tests
      • Iodine for starch
      • Benedict's solution for sugars
      • Biuret reagent for proteins
      • Ethanol for lipids
    • Respiratory system
      • Provides oxygen for respiration, removes carbon dioxide
    • Gas exchange
      1. Air moves down trachea, bronchi, bronchioles to alveoli
      2. Oxygen diffuses into blood, carbon dioxide diffuses out
    • Circulatory system
      • Double circulatory system, deoxygenated blood to lungs, oxygenated blood to body
    • Heart structure
      Right side pumps deoxygenated blood to lungs, left side pumps oxygenated blood to body
    • Blood vessels
      Arteries carry blood away from heart, veins carry blood towards heart
    • Coronary arteries supply the heart muscle with oxygen and nutrients
    • Cardiovascular disease

      Non-communicable disease affecting the heart and blood vessels
    • Other examples of non-communicable diseases include autoimmune conditions and cancer
    • Coronary artery
      Delivers blood to the heart muscle to supply oxygen
    • Heart attack
      Occurs when coronary arteries are blocked by buildup of fatty deposits, causing coronary heart disease (CHD)
    • Stents
      Little tubes inserted into blood vessels to keep them open and allow blood flow
    • Statins
      Drugs that reduce cholesterol, which reduces fatty deposits
    • Faulty heart valves
      Result in backflow, can be replaced with artificial ones
    • Blood
      Carries plasma, red blood cells, white blood cells (combat infections), and platelets (clot wounds)