Requirements Galen/Harvey extension Playdough model RBC sphygmomanometers

Objectives Students should learn: that blood is a tissue and consists of a fluid called plasma in which red blood cells, white blood cells and platelets are suspended that red blood cells contain a red pigment called haemoglobin, which transports oxygen that oxygen (in the lungs) combines with haemoglobin to form oxyhaemoglobin that blood plasma transports useful substances to the cells and removes waste products as the blood passes through the capillaries of the organs.

Outcomes Most students should be able to: describe the composition of the blood describe the structure of red blood cells and their role in the blood describe how oxygen is transported from the lungs to the other body organs by haemoglobin describe the structure and functions of the white blood cells and the platelets describe the functions of the blood plasma in the transport of substances around the body. Some students should also be able to: explain how red blood cells are adapted to carry out their function describe the reversible reaction between haemoglobin and oxygen.

Mark your Workbook homework p. 109,110,111 (heart, blood vessels) Answers are on page 17 in the answer book

Transport in the Blood B3 2.3 p.238

Specification Controlled Assessment: B4.3: Collect primary and secondary data. [B4.3.2 c) d) e)] B4.4: Select and process primary and secondary data. [B4.4.1 a) b)], [4.4.2 c)]

Which type of blood vessels?

What is blood made up of?

Blood Plasma The liquid part of our blood is called plasma. It transports red blood cells, white blood cells and platelets. Blood plasma is a yellow liquid which transports all blood cells and other substances around the body. Carbon dioxide produced as a by- product of aerobic respiration is carried in the plasma back to the lungs. It is the red blood cells which give blood its red colour.

Red Blood Cells Red blood cells pick up oxygen from your lungs and carry it to where it is needed for aerobic respiration. DID YOU KNOW? One red blood cell contains about 250 million molecules of haemoglobin which allow it to carry 1000 million molecules of oxygen There are more red blood cells than any other type of cell in your body – about 5 million in each cubic millimetre of your blood

A red blood cell has several features that help it do its job: Biconcave disc-shaped, with a dent on each side, creates a large surface area for gas exchange. A large surface area compared to volume, so oxygen is always close to the surface. Short diffusion distance How are red blood cells adapted to carry oxygen? It contains haemoglobin, a special pigment that combines with oxygen. It has no nucleus, so there is more space for haemoglobin and so more oxygen.

Gases moving in and out of the blood

The reversible reaction between oxygen and haemoglobin

The reversible reaction between oxygen and haemoglobin WHAT ORDER SHOULD IT BE? 1 Circulatory system transports the oxygen bound to the haemoglobin 2 Tissues respire using oxygen up 3 Oxygen diffuses from high to low concentration into the blood, and red blood cells In the lungs 4 Oxygen leaves the haemoglobin and diffuses from high to low concentration into the tissues 5 Haemoglobin binds oxygen in the blood

The reversible reaction between oxygen and haemoglobin In the lungs Oxygen diffuses from high to low concentration into the blood, and red blood cells Haemoglobin binds oxygen in the blood Circulatory system transports the oxygen bound to the haemoglobin oxyhaemoglobin Oxygen leaves the haemoglobin and diffuses from high to low concentration into the tissues Tissues respire using oxygen up

White Blood Cells Much bigger than RBCs and there are fewer of them. Have a nucleus and form part of the body’s self-defence system against harmful microorganisms. Some WBCs form antibodies against microorganisms. Other digest invading bacteria and viruses (phagocytosis).

Blood clotting (Platelets) At the site of a cut or wound the blood will clot. This prevents further blood loss, reduces the risk of pathogens entering and forms a framework for repairing the damaged tissue. Platelets will rapidly stick to a damaged area, releasing chemicals that start a series of complex reactions. This results in a network of protein threads that trap blood cells and more platelets to form a jelly-like clot. The clot dries and hardens to form a scab which protects the skin and stops bacteria getting into your body

Which component?

Blood under the microscope Try and focus in high power to see the cells

In your books – match up the correct words and statements about blood Component Function Plasma These cells form part of the body’s defence system against microorganisms. There are many different types. Red blood cells This liquid transports carbon dioxide from the organs to the lungs, soluble products of digestion from the small intestine to other organs, and urea from the liver to the kidneys. White blood cells These are small fragments of cells. They help blood to clot at the site of a wound. Platelets These cells transport oxygen from the lungs to the organs. They have no nucleus. They are packed with a red pigment called haemoglobin.

Draw a picture of each blood component and label it

Component% of blood Degrees on pie chart Plasma50 White blood cells1 Red blood cells45 Platelets4 The table below shows the relative quantities of each component in human blood. Convert the percentages to degrees and draw a pie chart in your books. Use a key to label your pie chart.

Q 1-3 p.239