Transport in Animals

Circular System Overview

Transport system in animals that moves blood, nutrients, gases, and wastes around the body. Components include heart, blood vessels, and blood.

Heart and Blood Vessels

• Heart: muscular organ pumping blood; has atria and ventricles.
• Arteries: carry blood away from heart (thick walls, high pressure).
• Veins: carry blood to heart (thin walls, valves to prevent backflow).
• Capillaries: thin-walled vessels for exchange of gases and nutrients.

Blood Components

• Red blood cells: transport oxygen.
• White blood cells: defend against pathogens.
• Platelets: aid in blood clotting.
• Plasma: transport nutrients, hormones, and waste.

Types of Circulation

• Systemic circulation: heart → body → heart.
• Pulmonary circulation: heart → lungs → heart.

Practice Questions

• Describe the structure and function of the heart. (5 marks)
• Differentiate between arteries, veins, and capillaries. (6 marks)
• List the components of blood and their functions. (5 marks)
• Explain systemic and pulmonary circulation. (4 marks)
• Short answer: Why do veins have valves? (1 mark)