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Biology Year 12 - Coggle Diagram

- - - - The width of the stomata depends upon turgidity of the guard cell the wider the wider the pore the greater the rate of transpiration.
    - - Open in the light and closed in the darkness very sensitive to carbon dioxide concentration High carbon dioxide concentration =closed carbon dioxide free =stay open
    - - A thick cuticle on the outer epidermal walls reduces transpiration
    - - The greater the number of stomata the faster the rate of transpiration
  - - - it is the number of moisture contained in the air at any given temperature compared to the amount of moisture that the air could hold at the temperature
    - - During high wind transpiration rate rate often falls due to the closure of the stomata
    - - If soil dries out less water can be absorbed by the and as a result the rate of transpiration decreases
    - - Causes stomata of most plants to open
    - - A rise in temperature increases the rate of evaporation, increase in water vapour
  - - - AS water evaporates from stomata more water is drawn across the mesophyll cells which in turn draws water out of the xylem cells. This transpiration pull places the water in the xylem under a tension which is transmitted downwards to the roots causing a column of water to move upwards through the plant a continues column of cohesive nature of water molecules when water is placed in tubes of very fine boro the force of attraction between the water molecules gives great strength to the column of water The column is then held at the top of the xylem vessels by the adhesion of the water molecules to the surface of the vessel walls
- - - - water flows in from a higher concentration of water molecules outside the cell to a lower concentration of water in the cell sap.
        
        cellwall stretches slightly cell becomes turgid.
        
        vacuole fills water pushing the cytoplasm against the cell wall
  - - - cell membrane pulls away from the cell wall as the vacuole loses water
        
        cell wall becomes soft cell becomes plasmolysis
        
        water flows from a higher concentration of water molecules in the cell sap to a lower concentration outside the cell
  - - - AS water evaporates from the leaves of the cut shoot the shoot sucks up water through the potometer the distance an air bubble moves in a period of time is used to calculate the rate of water uptake the syringe is used to allow the apparatus to reset.
    - - the weight potometer is used by measuring the weight lost by the plant the weight lost indicates how much water was taken up by the shoot
- - - - thin blood vessel exchange between blood and cell happens
        
        one cell thick to allow exchange between the blood and body cells
        
        low blood pressure no valves very small lumen
    - - carries blood under high pressure away from heart
        
        thick elastic fibres muscle strength expand and recoil
        
        High blood pressure no valves relatively small lumen
    - - carries blood back to heart
        
        thinner less muscle fewer elastic fibres
        
        low blood pressure has valves to prevent backflow relatively large lumen
  - - - responsible for transport of the blood cells food molecules carbon dioxide hormones urea , glucose phaty acids products of digestion like iron sodium potassium glycerol
    - - Help convert fribrigen to fibrin in blood clotting -the fibrin forms a mesh to trap the blood and is used in the formation of scabs
    - - transport oxygen - haemoglobin [oxygen binds]
        
        biconcave shape large surface area
        
        absence of nucleus allows it to carry more haemoglobin
- - - - Diet high in sugar + fat + salt
        
        Malnutrition lacks vitamins minerals other nutrients
        
        Obesity
        
        Heart disease -brittle bones
    - - Stronger bones , health heart + blood vessels
  - - - Addictive - increases heart rate