Page 149 - Primary Six Notes

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1. Red Blood Cell (erythrocytes)

 There are about 30 million red blood cells in a human body.

 They contain a red pigment called haemoglobin that con-

tains iron.

 They are made in red bone marrow of short bones like ster-

num, scapula, ribs, vertebra and pelvis.

 They do not have a nucleus.

 Their function is to transport oxygen in the body.

Adaptations of Red Blood Cells to Their Function

 They have haemoglobin which enables them carry more ox-

ygen molecules.

 They are produced in large number.

 They have no nucleus that provides a large surface area to

carry more oxygen.