Question

(a) Fig. 1.1 is a diagram of a cross-section through a vein. 

(i) Use a label and a label line on Fig. 1.1 to identify the:

• layer of muscle and elastic fibres
• lumen.

▶️Answer/Explanation

• Layer of muscle and elastic tissue labelled.
• Lumen labelled.

(ii) Name a structure that is present in veins but is not visible in Fig. 1.1. 

▶️Answer/Explanation

• Valve.

(b) Describe two ways in which the structure of capillaries is different from the structure of veins. 

▶️Answer/Explanation

• Capillaries have a narrower lumen compared to veins.
• Capillaries have thin walls, only one cell thick, whereas veins have thicker walls with muscle and elastic fibres.
• Capillaries do not contain muscular tissue or valves, unlike veins.

(c) Table 1.1 shows the names of three organs and some of the blood vessels connected to these organs. Complete Table 1.1. 

Organ	Blood vessel taking blood to the organ	Blood vessel taking blood away from the organ
Heart	Vena cava	……
Kidney	Renal artery	……
Lung	……	Pulmonary vein

▶️Answer/Explanation

Organ	Blood vessel taking blood to the organ	Blood vessel taking blood away from the organ
Heart	Vena cava	Aorta / Pulmonary artery
Kidney	Renal artery	Renal vein
Lung	Pulmonary artery	Pulmonary vein