Organisation in animals

• name the five levels of organisation

  Cells

  tissues

  organs,

  organ systems,

  organism
• what is a tissue?

  Group of cells with similar structures and functions
• what is an organ?

  Group of tissues working together to perform a specific
• what is the function of the liver digestion?

  Produces bile which neutralises hydrochloric acid from the stomach and fat to form small droplets with a large surface area
• what is the function of saliva in digestion?

  Lubrication to help swallowing contains amylase to breakdown starch
• name three enzymes produced in the pancreas

  amylase protease and lipase
• name the four components of the blood

  Red blood cells,

  white blood cells

  plasma

  platelets
• what's the function of platelets?

  The form blood clots prevent the loss of blood and stop wounds becoming infected
• how do white blood cells protect the body?

  engulf pathogens

  Produce antitoxins to neutralise toxins or antibodies
• name the substances transported in the blood plasma

  Hormones

  Proteins

  Urea

  Carbon dioxide

  Glucose
• why is the human circulatory system a double circulatory system?

  Blood passes through the heart twice every circuit around the body. The auction of blood is pumped from the right side of the heart of the lungs and the oxygenated blood that returns is pumped from the left side of the heart to the body.
• how does the structure of the artery relate to his function?

  Carries blood away from the heart under a high pressure

  Has a small lumen elasticated walls that can stretch
• how does the structure of the vein relate to its function?

  Carries blood back to the heart at a low pressure

  Has valves to prevent blood from wrong way
• how does the structure of a capillary relate to his function?

  Carries blood to cell and tissues

  Has a one cell thick wall to provide a short diffusion distance
• list the structures air passes through when breathin'

  Mouth/nose

  Trachea

  Bronchi

  bronchioles

  alveloi