Blood part 4 Introduce lesson with youtube video Explain red blood cells and white blood cells in detail. Assess the lesson using group work in an iquiz.

http://www.youtube.com/watch?v=UhqcB34AwpU

4 Blood Groups It is essential to know a persons blood group for safe blood transfusions Group A B AB O

Red Blood Cells No nuclei- when mature. When red blood cells are first made they have a nucleus. They lose it in a few days. They are then called red blood corpusles. No mitochondria. Biconcave- larger surface area. Flexible cell membrane.

Haemoglobin Joins with oxygen. In the lungs haemoglobin joins with oxygen to form Oxyhaemoglobin.

Oxyhaemoglobin is red. Haemoglobin loses oxygen easily so gives oxygen to cells with low oxygen.

White Blood Cells Phagocytes are the majority of white blood cells. (70%) Two other types are Lymphocytes and Monocytes. (30%)

Lymphocytes: made in the bone marrow. Stored in parts of the lymphatic system e.g the tonsils, adenoids, spleen. 25% of all white blood cells. Survive between 3 months and 10 years. A large nucleus that takes up most of the cell.

Function of lymphocytes: Makes antibodies that resist infection.

Monocytes Formed in bone marrow. About 5% of blood cells. Live for 6-9 days. Nuclei are shaped like a kidney.

Function: Engulf bacteria and digest it. Similar to phagocytes.

iQuiz

Homework. Pick a topic from a selection and write a paragraph on it. People will be picked to present it to the class.