Lesson Notes By Weeks and Term v5 - Grade 11

Lesson Video

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Performance objectives

• Describe the components of blood and their functions.
• Explain the role of haemoglobin in oxygen transport.
• Compare the different types of white blood cells.
• Describe the process of blood clotting.
• Explain the ABO and Rhesus blood group systems.

Lesson summary

The transport system in humans is a complex network responsible for delivering vital substances like oxygen, nutrients, and hormones to cells throughout the body and removing waste products like carbon dioxide and urea. Understanding this system is crucial for comprehending overall health and disease. For South African learners, appreciating the importance of healthy blood circulation is particularly relevant given the prevalence of conditions like hypertension, diabetes, and heart disease within our communities.

Lesson notes

The human transport system, also known as the circulatory system, is responsible for distributing essential substances and removing waste products from the body. It is composed of the heart, blood vessels, and blood. This week, we are focusing on blood.

Components of Blood: Blood is a specialized connective tissue composed of: Plasma: Plasma is the liquid component of blood, making up about 55% of its volume. It's a straw-colored fluid that consists of approximately 90% water, 8% plasma proteins, and 2% other solutes (glucose, amino acids, hormones, electrolytes, and waste products).

Functions of Plasma: Transporting blood cells, nutrients, hormones, and waste products. Maintaining blood volume and blood pressure. Regulating body temperature. Clotting (through clotting factors). Maintaining pH balance.

Red Blood Cells (Erythrocytes): Red blood cells are the most abundant cells in the blood, giving it its characteristic red color. They are biconcave discs, which increases their surface area for gas exchange. Mature red blood cells lack a nucleus, allowing more space for haemoglobin.

Haemoglobin: Haemoglobin is a protein found within red blood cells that contains iron. It has a high affinity for oxygen, enabling red blood cells to efficiently transport oxygen from the lungs to the tissues. It also carries some carbon dioxide back to the lungs.