GCSE BIOLOGY

Cards (100)

  • Define movement
    An action by an organism or part of an organism causing a change of position or place
  • Define respiration
    The chemical reaction that breaks down nutrient molecules in living cells to release energy
  • Respiration word equation
    Glucose+oxygen->water+carbon dioxide
  • Respiration symbol equation
  • Define sensitivity
    Ability to detect or sense changes in the environment and to make responses
  • Define growth
    A permanent increase in size and mass by an increase in cell number or cell size
  • Define reprouction
    Processes that make more of the same kind of organisms
  • Define excretion
    Removal from organisms of toxic materials, the waste product of metabolism and substances in excess requirement
  • Define nutrition
    Taking in of nutrients which are organic substances and mineral ions, containing raw materials or energy for growth and tissue repair, absorbing and assimilating them
  • Define cell
    The smallest structural and functional unit of an aorganism
  • State differences between the typical animal and plant cell
    -Only plant cells have chloroplasts and cell walls
    -Shape of plant cell is more regular
    -Animal cells store carbohydrates as glycogen, plant cells store carbohydrates as starch
  • Function of nucleus (cell)
    Contains DNA (Genetic material), which controls cell activity
  • Function of cytoplasm
    Where chemical reactions take place
  • Function of cell membrane
    Partially permeable membrane which controls substances that move in and out of the cell
  • Function of cell wall
    Strengthens and protects the cell
  • Function of chloroplast
    Contains chlorophyll which absorbs light energy for photosyntheis
  • Word equation for photosynthesis
    Carbon dioxide+water->Oxygen+glucose
  • Symbol equation fo photosynthesis
  • Function of vacuole
    Filled with cell sap which helps keep the cell turgid
  • Function of red blood cell
    Carries oxygen around the body to all respiring tissues
    (Contains haemoglobin which picks up oxygen)
  • How the red blood cell is suitable for its function
    -Biconcave shape (Higher surface area)
    -No nucleus (Can move around more easily and allows the cell to hold more oxygen)
  • Function of root hair cell
    To absorb water and mineral ions for the plant (vis osmosis
  • How the root hair cell is suitable for its function
    -Elongated section to its main body (Higher surface area)
    -Membrane of the root is semi permeable (only water and minerals can go through)
  • Define diffusion
    The net movement of molecules form a region of high concentration to a region of lower concentration down a concentration gradient (Result of random movement/brownian motion)
  • Importance of diffusion in gases
    -Necessary for gas exchange in living organisms
    -Necessary for photosynthesis
  • Importance of diffusion in water as a solvent
    -Absorption of minerals in plants (minerals salt needs to dissolve in water)
    -Necessary for excretion (pee)
  • Define osmosis
    The diffusion of water molecules from a region of high concentration to a region of lower concentration through a semi permeable membrane
  • Osmosis in plant cells
    -Water enters the root hair cell through osmosis
    -If vacuoles aren't full of water the cell will become flaccid causing the plant to will
  • Osmosis in animal cells
    -If surrounded with high water potential, water will enter the cell, if to much water ends up in the cell it will burst
    -If surrounded with low water potential, water in cytoplasm will diffuse outwards causing the cell to shrink
  • Define enzyme
    Proteins that function as biological catalysts (speeds up reaction in living cells)
  • Define substrate molecule
    A substance on which enzymes act on
  • Define active site
    A region on an enzyme which binds to the substrate during a reaction
  • Explain the lock and key mechanism for enzymes
    An enzyme has to be the right shape for the substrate to fit into. An enzyme will only accept 1 substrate (1 specific chemical reaction)
  • Temperatures effect on enzymes
    -As temperature increase so does the rate of reaction, up to a certain point. This point is known as the "optimum temperature". If the temperature goes above this enzyme activity will decrease (denature)
    -If the temperature is to low the enzyme will be dormand
  • PHs effect on enzymes
    -Different enzymes work best at different PH s
    -If the PH is to low OR to high the enzyme will denature
  • Function of protease
    Breaks down protein
  • Function of amylase
    Breaks down starch
  • Function of lipase
    Breaks down fats and oils
  • Denature
    Change in the structure of the enzyme
  • What is starch and glycogen made up of
    Glucose