Histology Of Large Intestine, Appendix and Rectum

Question 1

Large Intestine
•Appox. —— long
•divided into several regions.
•It consists of: ——-

Answer 1

Large Intestine
•Appox. 1.5m long
•divided into several regions.
•It consists of: cecum, appendix, colon, rectum and anal canal.

Question 2

The Cecum
• is continuous with the ileum at the —— junction and forms a blind pouch at the proximal end of the colon.

Answer 2

The Cecum
• is continuous with the ileum at the ileocecal junction and forms a blind pouch at the proximal end of the colon.
• It bears the appendix, a small, slender diverticulum.

Question 3

The mucosa shows numerous closely arranged tubular glands or crypts similar to those in the small intestine called

Answer 3

Crypts of lieberkuhn

Question 4

Colon Histological Features— Mucosa
❖ The lumen is lined by a —— - epithelium

Answer 4

Simple columnar

Question 5

• Intestinal glands of the colon are —— and more ——- than those in the small intestine,

Answer 5

• Intestinal glands of the colon are longer and more closely packed than those in the small intestine,

Question 6

Colon Histological Features— Mucosa
❖ The glands contain numerous —— cells, —— cells and in the basal half of the glands, ——- and —— cells.

Answer 6

Colon Histological Features— Mucosa
❖ The glands contain numerous goblet cells, endocrine cells and in the basal half of the glands, proliferating and undifferentiated epithelial cells.

Question 7

Colon Histological Features— Submucosa
❖ The submucosa of the colon is similar to that of the small intestine
❖ Contains the larger blood vessels and the submucosal nerve plexus. —— are not present.

Answer 7

Glands

Question 8

Colon Histological Features— Submucosa
❖ Often contains fat cells.
❖ Some cells that contain PAS-positive granules, termed ——, are also present.
❖ These are most numerous in the ——.

Answer 8

Colon Histological Features— Submucosa
❖ Often contains fat cells.
❖ Some cells that contain PAS-positive granules, termed muciphages, are also present.
❖ These are most numerous in the rectum.

Question 9

Colon Histological Features— Muscularis Extenal
❖ The outer, longitudinal coat of the muscularis externa of the cecum and colon differs from that of the small intestine in that it is collected into three longitudinal bands called the ———

Answer 9

Taeniae coli

Question 10

❖ Due to the tonus of the taeniae coli, the wall of the colon is gathered into outwardly bulging pockets, called the ——-.

Answer 10

Haustra

Question 11

Colon Histological Features— Serosa
􏰀 The serosa is incomplete in the colon, as the ascending and descending portions of the colon are ——peritoneal.
􏰀 Here the muscular wall of the colon is attached to adjacent structures by an ——.
􏰀 Where a serosa is present, it may contain large, pendulous lobules of fat called ——.

Answer 11

Colon Histological Features— Serosa
􏰀 The serosa is incomplete in the colon, as the ascending and descending portions of the colon are retroperitoneal.
􏰀 Here the muscular wall of the colon is attached to adjacent structures by an adventitia.
􏰀 Where a serosa is present, it may contain large, pendulous lobules of fat called appendices epiploicae.

Question 12

Is tenia coli present in the appendix

Answer 12

No

Question 13

Is there tenia coli in the rectum

Answer 13

No

Question 14

Where does peritoneum cover in the rectum

Answer 14

Peritoneum covers the front and sides of the upper one-third of the rectum; and only the front of the middle third.
There is no covering in the lower third

Question 15

The Ana Canal
• about —— cm long. The upper part is —cm long, lined by ——-/,
• lower part is —— cm covered by —-/.
• The area lined by mucous membrane can be further divided into an upper part (—mm) and a lower part (— mm).

Answer 15

The Ana Canal
• about 4 cm long. The upper 3 cm
• lined by mucous membrane,
• lower 1 cm by skin.
• The area lined by mucous membrane can be further divided into an upper part (15 mm) and a lower part (15 mm).

Question 16

The Ana Canal
• The mucous membrane of the upper 15 mm of the canal is lined by ——— epithelium.
• The mucous membrane of this part shows how many to how many longitudinal folds that are called the ——.

Answer 16

The Ana Canal
• The mucous membrane of the upper 15 mm of the canal is lined by columnar epithelium.
• The mucous membrane of this part shows six to twelve longitudinal folds that are called the anal columns.

Question 17

The Anal Canal
• The anal valves together form a transverse line that runs all round the anal canal: this is the ———.
• At the pectinate line, the simple columnar intestinal epithelium makes an abrupt transition to noncornified ——— epithelium.

Answer 17

The Ana Canal
• The anal valves together form a transverse line that runs all round the anal canal: this is the pectinate line.
• At the pectinate line, the simple columnar intestinal epithelium makes an abrupt transition to noncornified stratified squamous epithelium.

Question 18

The Ana Canal
• Beneath the epithelium of this region are simple tubular apocrine sweat glands, the ——- glands

Answer 18

Circumanal

Question 19

The Anal Canal
• The mucosa has a —— color appearance because of the presence of a dense venous plexus between it and the muscle coat.

Answer 19

The Ana Canal
• The mucosa has a bluish appearance because of the presence of a dense venous plexus between it and the muscle coat.

Question 20

The Ana Canal
• The mucosa has a bluish appearance because of the presence of a——.

Answer 20

The Ana Canal
• The mucosa has a bluish appearance because of the presence of a dense venous plexus between it and the muscle coat.

Question 21

The Ana Canal
• The lowest 8 to 10 mm of the anal canal are lined by true skin in which ——,——glands and ——glands are present.

Answer 21

Hair follicles
Sebaceous glands
Sweat glands

Question 22

Mass movement starts from which colon , how many times and triggers which reflex

Answer 22

Middle of Transverse colon
2-3
Defecation