Please enable JavaScript.

Coggle requires JavaScript to display documents.

Biology Paper 1 - Coggle Diagram

- - - - Amylase breaks down starch into glucose.
    - - Protease breaks down proteins into amino acids
    - - Lipase breaks down lipids into fatty acids and glycerol.
    - - Carbohydrates are broken down by carbohydrase into simple sugars
- - - - Oxygen The lungs All the body's cells
      - Carbon dioxide All the body's cells Lungs
      - Glucose Digestive system The liver, then all the body's cells
      - Urea Liver cells Kidneys
    - - Blood enters the heart through the atria. Blood from two vena cavae enters the right atrium. Blood from the pulmonary veins enters the left atrium.The atria fill, followed by the ventricles. Blood is prevented from flowing back into the atria by heart valves.
      - Blood leaves the heart in the body's main artery - the aorta - from the left side, and the pulmonary artery, from the right.
      - Double circulation
      - Humans have a double circulatory system. The heart pumps blood through two circuits:
      - the pulmonary circulation
      - the systemic circulation
      - The pulmonary circulation transports blood to the lungs. At the lungs:
      - oxygendiffuses into the blood from the alveoli - the blood becomes oxygenated
      - carbon dioxide diffuses from the blood into the lungs
    - - Blood is transported in arteries, veins and capillaries.
        
        Blood is pumped from the heart in the arteries. It is returned to the heart in the veins.
        
        The capillaries connect the two types of blood vessel and molecules are exchanged between the blood and the cells across their walls.
        
        Arteries
        
        Always carry blood away from the heart
        
        Carry oxygenated blood, except for the pulmonary artery
        
        Carry blood under high pressure
        
        Have thick muscular and elastic walls to pump and accommodate blood
        
        A type of supporting tissue called connective tissue provides strength
        
        The channel in the blood vessel that carries blood - the lumen - is narrow
        
        Veins
        
        Have a wide lumen
        
        Have less connective tissue than arteries
        
        Have thin walls - have less muscular tissue than arteries
        
        Carry blood under low or negative pressure
        
        Always carry deoxygenated blood, except for the pulmonary vein
        
        Always carry blood to the heart