Question

Adventitia is the outermost coat of.
A. Stomach
B. Intestine
C. Rectum
D. Artery

Answer 1

Hint:-The word “Adeventia” is derived from Latin word “adventicus” meaning- extraneous that
means something that is coming from outside or present outside.
- Adventitia is a connective tissue.
-It surrounds any organ, vessel, blood vessel.
- It is also composed of fibroblast, blood vessels, collagenous connective tissue, nerve etc.

Complete step-by-step solution:-Adventitia is a thin layer which is composed of collagen and elastic fibers.
-Its main function is to protect the vessel from excessive extension and recoil.
-It forms the outer layer of the connective tissue that surrounds an artery or a vein.
-The tunica externa the outermost layer of the blood vessel.
-Tunica externa is also called tunica adventitia.
-The adventitia forms the covering of the following:
I. Oral cavity
II. Thoracic esophagus
III. Ascending colon
IV. Descending colon
V. Rectum
The options given in the question are discussed below:
A. Stomach- stomach layer is made up of 4 layers that are-
-Mucosa- it is the innermost layer of the stomach
- Submucosa- the second layer that supports the mucosa
-Muscularis- the third layer made up of muscles
-Submucosa- the next layer which acts as a supporting layer to the serosa
-Serosa- it is the outermost layer of the stomach
B. Intestine- intestine is made up of the following layers:
-Mucosa- innermost layer consists of epithelium, lamina propria, muscularis mucosae.
-Submucosa- connective tissue layer,
-Muscularis externa- the layer made up of smooth muscle
-Serosa- the outermost layer which is covered by mesothelium.
C. Rectum- the wall of the rectum is made up of 5 layers.
-Mucosa- lined by columnar epithelium
-Deep mucosa- made up of lamina propria and muscularis mucosae
-Submucosa
-Muscularis propria- it is inner circular and the outside made of longitudinal layers.
-Serosa- forms the outermost layer which is made up of fat.
D. Artery- the artery is made up of the following layers:
-Tunica intima- it forms the innermost layer which is made up of squamous epithelium

-Tunica media- it forms the middle layer which is made up of smooth muscle which is thickest
later.
-Tunica external or tunica adventitia- forms the outermost layer of the artery which is made
up of connective tissue.
Adventitia is the outermost layer of the artery. The correct answer is option D.

Note:- The serosa and the adventitia are almost similar in structure but they differ in the tissue that lines them.
-The serosa is surrounded by visceral peritoneum
-Adventitia is surrounded by connective tissue.