Question

(a) Draw a sectional view of the human heart and label on it – Aorta, Right ventricle and Pulmonary veins. 

(b) State the functions of the following components of transport system: 

(i) Blood (ii) Lymph

Answer 1

(a)

(b) The functions of blood and lymph are as follows: 

(i) Blood 

• Oxygen is transported by the blood to the tissues of the body for the breakdown of digested food. 
• Carbon dioxide is transported to the lungs by the blood plasma. 
• The digested and absorbed nutrients are transported by blood to the tissues. Nitrogenous wastes are transported to the kidneys. 
• It regulates the body temperature and maintains the pH of the body tissues. 
• It transports various hormones from one region to another and bring about the coordination. 
•  It maintains water balance to constant level.
•  The lymphocytes produce antibodies against the invading antigens and protect from diseases. 
• It helps in rapid healing of wounds by forming a clot at the site of injury. 

(ii) Lymph 

• It cleans the cellular environment. 
• It returns proteins and tissue fluids to the blood (drainage) 
• It provides a pathway for the absorption of fats and fat-soluble vitamins into the bloodstream. 
• It defends the body against disease