Question

 Given below is the simplified pathway of the circulatory system:

(i) Name the blood vessels marked 1 to 8.
(ii) Name the chamber of the heart which:
(a) Receives blood from ‘1’.
(b) Pumps blood into blood vessel ‘8’.
(iii) Mention two structural differences between blood vessels ‘7’ and ‘2’.

Answer 1

(i)
1. Pulmonary vein
2. Dorsal aorta,
3. Hepatic portal vein
4. Renal artery
5. Iliac vein
6. Hepatic vein
7. Inferior vena-cava
8. Pulmonary artery.
(ii) (a) Left auricle.
    (b) Right ventricle.
(iii) (a) The inferior vena cava arises from iliac veins coming from the hind limbs, while the dorsal aorta arises from the left ventricle and continues behind as the abdominal aorta.
(b) The deoxygenated blood is collected by the inferior vena cava, while the branches of the dorsal aorta supply oxygenated blood to the body parts.