MASTERY LEARNING IN AIDS PHYSIOLOGY

This OBE project has three parts. The first will be teacher centred and help students to draw the diagrams and trace the flow involved. They can be helped by the grade 12 textbook by McKean.

The second part requires students to practise the diagrams and explanations. The third part will be totally student centred and require them to master the diagrams and explain the processes with some new interpratation required.

DRAW THE BLOOD SYSTEM. Include the heart, lungs, arteries to the head, legs, intestines, kidneys, liver and genitals. Show the differences between arteries and veins.

DRAW THE LYMPH SYSTEM. Show the two main vessels leading upwards, entry of vessels into the main veins or vena cava leading to the heart, entry to genitals, anus, spleen, long bones and thymus.

DRAW SMALL AND LARGE INTESTINES. Show on an enlarged diagram the villi, arteries, veins, capillaries leading to the small and large intestines, epithelial layer, CD4 cells anchored in the gut wall and lymphatics leading into the lymph system.

TRACE HIV FROM GENITALS TO GUT. Show connections of genital and anal mucosa into the lymph system and the groin lymph nodes of the groin. Trace up to the vena cava, through the heart, down the arteries and into the small intestine and gut lining.

TRACE NUTRIENTS FROM GUT. Show passage from the digestive system, through the epithelial layer, entry to veins, passage to liver by hepatic portal vein, then dispersed from liver to tissues and cells.

TRACE FAT FROM GUT. Show passage through villi to lymphatics, movement up to the vena cava, down through the heart, down to the body tissues. Show by coloured pen, the build up of fatty plaque in the lymph vessels, vena cava, heart and arteries.

TRACE HIV REPLICATED IN GUT CD4. Show breakout from CD4 of gut lining, entry to veins and circulation in the blood and lymph systems.

The final testing can involve the students in some interpretation and analysis of the processes. They should have understanding of the function of the body systems by now.

What is the effect of HIV damage to thymus and long bones?  Damage to the thymus will stop manufacture of CD4 T cells. Damage to the long bone marrow will harm the production of red and white cells.