gastricpit

gastricgastric

glandgland

stomach large intestinesmall intestine

lamina muscularis mucosae

inte

stin

alvi

lli

inte

stin

alg

lan

ds

inte

stin

alg

lan

d

lamina propria

stomach large intestinesmall intestine

goblet cell

enteroendo-crine cell

enterocyte

anatomical (macroscopic) features

> taeniae coli

> longitudinal layer of muscularis is split into 3 bands

> absent from the appendix and rectum

> haustra coli (colic sacculations)

> outpocketings between two semilunar folds

> appendices epiploicae / appendices omentales

> serosa-covered appendages containing adipose tissue

general histological (microscopic) features

> (1) concomitant special properties:

> has intestinal glands (crypts of Lieberkühn)

> lacks intestinal villi

> (2) ratio of goblet cells to enterocytes is much larger in the largeintestine than in the small intestine

histological (microscopic) feature of appendix

> aggregated lymphatic follicles (folliculi lymphatici aggregati)

> are found as a complete ring in the wall of the appendix

(tela subserosa and/or lamina propria mucosae)

ileumappendix

vermiformis

mesentery meso-appendix

the last segment of the rectum

> proximal boundary

> beginning of anal / rectal column of Morgagni

(anorectal line)

(> pelvic diaphragm; levator ani muscle)

> distal boundary

> anus

> portions of anal canal (different covering epithelia)

> zona columnaris

> zonazona intermediaintermedia / / zonazona haemorrhoidalishaemorrhoidalis

> zona cutanea

external anal sphincter (striated m.)

middle rectal v.

venous plexus in the submucosa

adipose tissue

anal column

anal sinus

columnariscolumnaris--haemorrhoidalishaemorrhoidalis boundaryboundary

perineal skin

anus, skin

levator ani m. (striated m.)

internal anal sphincter (smooth m.)

longitudinal layer (smooth m.)

circular layer (smooth m.)

inferior rectal v.

haemorrhoidalishaemorrhoidalis--cutaneacutanea boundaryboundary

epitheliumepithelium ofof thethe analanal columncolumnepitheliumepithelium ofof thethe analanal sinussinus

circumanal gl. (apocrine sweat gl.)

sebacous gl. (holocrine gl.)