In this chapter, learners will be introduced to the circulatory system in humans. The chapter starts with an introduction of different types of circulatory systems found in animals.
Learners will then spend some time studying the pulmonary and systemic circulatory systems; the internal and external structure of the heart; the cardiac cycle and the different types of blood vessels. A brief overview of the lymphatic circulatory system follows. The chapter concludes with an overview of some diseases that affect the cardiovascular system, as well as their treatments.
There are two important practicals in this chapter. In the first practical investigation, learners will need to dissect an animal heart in order to examine the structure of the heart. In the second investigation, learners will evaluate the effect of exercise on heart-rate. This activity should be conducted in the form of a scientific experiment, with an hypothesis, method, analysis of results and conclusion.
All living organisms require oxygen and nutrients, and a method of removing carbon dioxide and waste products. However, the circulatory system is not limited to the delivery of nutrients, gas exchange, and waste removal. Hormones, too, rely on the circulatory system to reach target organs, and the immune system depends on the transport of white blood cells and antibodies. This chapter discusses transport systems found in mammalian systems, with a focus on transport systems found in humans.
TEACHERS RESOURCE:
The following website has interactive activities that summarise different material covered in this chapter. The different activities are best done when the relevant material is covered: