Intestines

Question 1

Answer 1

Duodenum - small intestine

Mucosa has characteristic villous form of the whole of the small intestine, interspersed with short glands known as crypts of Lieberkuhn.

B Brunner’s glands CM inner circular layer of muscularis propria SM submucosa LM outer longitudinal layer of muscularis propria MM muscularis mucosae V villi

Question 2

Answer 2

Ileum - small intestine

CM inner circular layer of muscularis propria LM outer longitudinal layer of muscularis propria Sr serosa MM muscularis mucosae SM submucosa PC plicae circulares M mucosa P Peyer’s patches V villi

Question 3

Answer 3

Human duodenum

Duodenal mucosa has typical form found elsewhere in small intestine: numerous elongated villi

C crypts LP lamina propria MM muscularis mucosae SM submucosa V villi

Question 4

Answer 4

Intestinal villi and crypts

C crypts LP lamina propria MM muscularis mucosae SM submucosa V intestinal villi

Question 5

Answer 5

Villous core

C capillaries P plasma cells Ly lymphocytes Mu smooth muscle fibres

Question 6

Answer 6

Luminal surface of enterocytes

C capillaries

Question 7

Answer 7

Top view of villi

L lacteal Ly lymphocytes

Question 8

Answer 8

Crypts of Lieberkuhn

E endocrine cells P paneth cells

Question 9

Answer 9

Crypts of Lieberkuhn

E endocrine cells G goblet cells Mt mitotic figure P Paneth cells

Question 10

Answer 10

Crypts of Lieberkuhn

P Paneth cells

Question 11

Answer 11

Ileocaecal junction

L large intestine Ly lymphoid tissue (large Peyer’s patches) M muscularis propria S small intestine

Ileocaecal valve consists of a thickened extension of the musculari propria

Question 12

Answer 12

Colon

CM inner circular layer of muscularis propria LM outer longitudinal layer of muscularis propria LA lymphoid aggregate

Question 13

Answer 13

Colon (x100)

MM muscularis mucosae

Closely packed straight tubular glands, or crypts, extend into the MM.

Question 14

Answer 14

Trasnverse sections through the upper part of large intestinal glands

Highlights closely packed arrangement of the glands in the mucosa

T lymphocytes

Question 15

Answer 15

Appendix

F lymphoid follicle M mesentery LP lamina propria S outer serosal layer

Question 16

Answer 16

Appendix

LP lamina propria SM submucosa

LP and SM diffusely infiltrated with lymphocytes. Mucosal glands are much less closely packed than in the large intestine.

Question 17

Answer 17

Recto-anal junction

J ecto-anal junction RM rectal mucosa SS stratified squamous epithelium (anal canal)