Sciences - Co-ordinated (9-1) - 0973 CIE

Blood

Overview

Blood is far more than a red liquid. It is a living tissue: red cells packed with oxygen, white cells hunting invaders, tiny platelets ready to seal a wound, all carried in a straw-coloured fluid that ferries food, waste, hormones and heat around your body.

In this lesson you will learn the four components of blood and what each one does, and how to recognise red and white cells. Extended students will tell phagocytes from lymphocytes, learn their separate roles in defence, and follow the chemistry of how a clot forms.

Objectives

List the components of blood as: red blood cells, white blood cells, platelets and plasma
Identify red and white blood cells in photomicrographs and diagrams
State the functions of the following components of blood: (a) red blood cells in transporting oxygen, including the role of haemoglobin (b) white blood cells in phagocytosis and antibody production (c) platelets in clotting (details are not required) (d) plasma in the transport of blood cells, ions, nutrients, urea, hormones and carbon dioxide
State the roles of blood clotting as preventing blood loss and the entry of pathogens
[Supplement] Identify lymphocytes and phagocytes in photomicrographs and diagrams
[Supplement] State the functions of: (a) lymphocytes - antibody production (b) phagocytes - engulfing pathogens by phagocytosis
[Supplement] Describe the process of clotting as the conversion of fibrinogen to fibrin to form a mesh

Lesson Note

Blood links almost every system in the body: transport, gas exchange, defence and repair all depend on it. Knowing the job of each component lets you answer questions across the whole syllabus, from how oxygen reaches a muscle to how the body fights an infection.

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Lesson Evaluation

Congratulations on completing the lesson on Blood. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.

You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.

Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.

Which part of the blood is packed with haemoglobin and carries oxygen around the body? A. white blood cells B. red blood cells C. platelets D. plasma Answer: B
The liquid part of blood is called: A. plasma B. serum only C. haemoglobin D. fibrin Answer: A
Blood clotting helps to: A. carry oxygen B. prevent blood loss and entry of pathogens C. produce hormones D. digest food Answer: B
[Supplement] Antibodies are produced by: A. red blood cells B. platelets C. lymphocytes D. plasma Answer: C
[Supplement] During clotting, fibrinogen is converted into: A. haemoglobin B. fibrin C. plasma D. platelets Answer: B