Transport Systems

• Blood delivers…

  oxygen and glucose to every cell and removes wastes like carbon dioxide
• Red blood cells

  Millions in a single blood drop

  No nucleus - packed with haemoglobin

  Biconcave shape

  Haemoglobin combines easily with oxygen
• White blood cells

  Larger but less numerous

  Immune system
• White blood cells-Phagocytes

  Engulfing and digestion of microbes

  Lobed nucleus
• White blood cells-Lymphocytes

  Make and send out antibodies which make microbes stick together so engulfing cells can kill them

  Single large nucleus
• Platelets

  Small fragments of cells

  No nucleus

  Produces substances that help blood to clot at a wound
• Plasma

  Pale yellow liquid

  Carries blood cells

  Carries dissolved substances:

  CO2

  Glucose

  Amino acids

  Urea

  Antibodies
• Arteries

  Travel away from the heart

  Blood is under high pressure so a

  Thick elastic layer is needed to

  Allow expansion and recoil Carries oxygenated blood
• Veins

  Travel towards the heart

  Blood under low pressure so

  Thinner elastic

  Wide lumen to help blood flow

  Has valves to prevent backflow Carries deoxygenated blood
• Capillaries

  Tiny

  Deliver oxygen and glucose

  Remove wastes

  Walls one cell thick for diffusion

  Red blood cells go through in single file

  Epithelial cell
• At lungs

  Oxygen into red blood cells and

  Combines with haemoglobin

  Carbon dioxide moves out of plasma and into lungs
• At body cells

  Oxygen, glucose, amino acids enter cells

  Carbon dioxide, urea leave cells
• Function of the heart is to

  pump blood around the body
• Left side of heart is

  oxygenated blood
• Right side of heart is

  deoxygenated blood
• Why is the left side of the heart stronger?

  Has a thicker muscle wall to pump blood with a greater force to travel around the whole body whereas the right side only needs to pump blood to the lungs
• Heart is supplied glucose + oxygen


  by the coronary artery
• If the hearts supply of glucose + oxygen is blocked

  it is called cardiac arrest or a heart attack
• Heart attack

  Narrow coronary artery

  Red blood cells clot

  Blood flow to cardiac muscle stops

  Muscle cells die to lack of glucose and oxygen as respiration can’t occur
• Arteries become narrowed by

  Fatty deposits being laid on the surface

  More likely for red blood cells to clot
• What is fatty build up in arteries caused by?

  High saturated fat, cholesterol and salt in diet

  Smoking and high blood pressure

  Obesity

  Lack of exercise
• How can we prevent heart attacks?

  Eating little saturated fat and salt

  Exercising regularly

  Reducing stress

  Reducing smoking
• Plant transport


  Leaves are covered in stomata to allow gas exchange
• Plant cells to carry water

  Xylem

  Water moves up these tubes

  Also transport mineral salts(dissolved in water)
• Water movement is

  Transpiration
• Factors that affect transpiration

  Windspeed

  Temperature

  Humidity
• Plant cells to carry sugar

  Phloem

  Carries in two directions

  Down to roots for use or storage

  Up to buds, flowers, fruit, leaves for growth and maturation
• Sugar movement is

  translocation