Blood and its composition
Answers are for parents and teachers.
1
Write the three functions of blood, each with one example.
Transport – carrying oxygen; regulation – delivering hormones; protection – leukocytes swallowing microbes.
2
Compare plasma and formed elements in a table.
Plasma: liquid part, 90% water, proteins. Formed elements: erythrocytes, leukocytes, platelets; made in red marrow.
3
Why is clotting important when injured?
It stops bleeding and makes it harder for microbes to enter.
4
Write the clotting process in 5 steps.
Vessel damage; platelets break; prothrombin → thrombin; fibrinogen → fibrin; clot closes the wound.
5
If bleeding from a small wound does not stop for a long time, what should be done?
Press with a clean cloth, tell an adult and see a doctor.