Question

The aorta is the largest artery found in the body which carries oxygen-rich blood away from the heart as it begins the systemic blood flow circuit throughout the body. Owing to the fact that the aorta connects to the heart, the blood pressure inside the aorta is very high. As blood travels further from the heat, BP gradually decreases. Based on the understanding that walls of the aorta are exposed to highly extreme outward pressure, hypothesize the order of specific tissue types one would expect to find in the aorta (From Deep to Superficial) and explain your reasoning.

Answer 1

Going from lumen to the outer layer of aorta, the following types of cells are expected to be present:

1. Endothelial cells : these cells line the inner wall of aorta towards the lumen. This is the first layer because endothelial cells act as a barrier against blood leaking into the other layers due to high rate of flow.

2. Internal elastic lamina and membrane : elastic fibres form the elastic lamina as the next layer. This facilitates the expansion of aorta in case of high blood flow.

3. Smooth muscle : the next layer consists of smooth muscle. This automatically controls the flow of blood in aorta.

4.external elastic lamina : this layer again contains elastic fibres to support the pressure in the aorta.