Question

The diagrams given are cross sections of blood vessels.
$\left(i\right)$ Identify the blood vessels $A,B$ and $C$.
$\left(ii\right)$ Name the parts labelled $1$ to $3$.
$\left(iii\right)$ Name the type of blood that flows through $A$.
$\left(iv\right)$ Mention one structural difference between $A$ and $B$.
$\left(v\right)$ In which of the above vessels does exchange of gases actually take place?

Answer 1

(i) A = Artery

B = Vein

C = Capillary

(ii) 1. Connective tissue layer

2. Lumen

3. Muscular layer

(iii) Oxygenated blood

(iv) A has thick muscular and elastic layer as a wall with narrow lumen whereas B has a thin muscular layer, a less elastic wall with the wide lumen.

(v) In a capillary vessel, the exchange of gases like oxygen and carbon dioxide actually takes place.