Md1 Histology Block 3 Digestive System 2

Front 1

digestive tube is differentiated into four major organs:

Back 1

esophagus
stomach
small intestine
large intestine

organs is made up of four concentric layers

Hint 1

mucosa
submucosa
muscularis externa
adventitia, or serosa

Front 2

Mucosa layer

Back 2

lining epithelium
mucosal glands

lamina propria
loose connective tissue

smooth muscle (not a lot of Myo)
a thin inner circular layer

Front 3

Submucosalayer

Back 3

dense irregular connective

also called Meissner's) nerve plexus

Front 4

Muscularis externa layer
***

Back 4

internal sublayer (close to the lumen), the orientation is generally circular (Inner circular)
I-I

external sublayer, it is mostly longitudinal (outer longitudinal).
O-O
contains the myenteric (or Auerbach's)

Front 5

Serosa

Back 5

thin layer of loose CT
rich in blood
lymph vessels
adipose tissue
simple squamous covering

In the abdominal cavity, the serosa is continuous with the mesenteries

Front 6

Nerve supply of the digestive tube
innervated by

Back 6

autonomic nervous system (ANS).

Front 7

***Nerve supply of the digestive tube
Sympathetic nerve fibers derive from the

Back 7

thoracic and lumbar spinal cord.

Front 8

***Nerve supply of the digestive tube
Parasympathetic nerve fibers derive from the

Back 8

vagal dorsal motor nucleus of the medulla oblongata.

Front 9

***Nerve supply of the digestive tube

Visceral sensory fibers originate in the

Back 9

spinal dorsal root ganglia.

Front 10

The intrinsic or enteric innervation is represented by two distinct interconnected neuronal circuits formed by

Back 10

sensory
motor
linked by interneurons

Hint 10

the submucosal plexus of Meissner, present in the submucosa

myenteric plexus of Auerbach, located between the inner circular and outer longitudinal layers of the muscularis.

Front 11

The integrated extrinsic and intrinsic (enteric) networks regulate and control
2ct

Back 11

peristaltic contractions
secretory act

Front 12

Stimulation of preganglionic parasympathetic nerve fibers
of the muscularis causes increased motility as well as glandular secretory activity.

Back 12

cholinergic terminals

Front 13

Hirschsprung disease (congenital megacolon) or Chagas' disease (Trypanosoma cruzi infection), the plexuses in the digestive tract are severely injured and most
is what kind of Dz =

Back 13

Nerve Dysfunction

plexuses in the digestive tract are severely injured and most of their neurons are destroyed.

Front 14

Stimulation of postganglionic sympathetic nerve fibers
on the smooth muscle cells causes decreased motility.

Back 14

adrenergic terminals

Front 15

Esophagus

Back 15

stratified squamous nonkeratinizing


Both the mucosa and the submucosa in the undistended esophagus form longitudinal folds

Info

Hint 15

muscularis mucosae is not present in the upper portion of the esophagus, but it becomes organized near the stomach.

Front 16

Rupture of the varices or ulceration of the overlying mucosa can produce hemorrhage into the esophagus and stomach, often causing vomiting

S/S =

Back 16

hematemesis

Front 17

An increase in pressure in the portal venous system, caused by chronic liver

Back 17

esophageal varices.

Front 18

Esophagus
Mucosal and submucosal glands are found in the esophagus. Their function is to produce

Back 18

mucosal tubular glands
cardiac esophageal glands.
submucosal tubuloacinar glands

Front 19

At the distal end of the esophagus, the muscular layer consists of only
what muscle cells =

Back 19

smooth muscle cells

Front 20

Esophagus
mid portion, a mixture of what muscle cells =

Back 20

striated and smooth muscle cells;

Front 21

Esophagus
at the proximal end contain what muscle cells =

Back 21

only striated muscle cells.

Front 22

the esophageal stratified squamous lining epithelium may be replaced at the lower end by a poorly resistant is replaced by =

Back 22

columnar epithelium

reflux esophagitis or ulceration

Front 23

Condition in which normal squamous epithelium of esophagus
has been replaced by abnormal columnar epithelium.

Back 23

Barrett’s esophagus

Front 24

At the gastroesophageal junction, the epithelium changes from

Back 24

from stratified squamous
to a
simple columnar

Front 25

Stomach Mucosa Layers

The epithelium covering the surface and lining the pits is

Back 25

simple columnar epithelium,
and
all the cells secrete an alkaline mucus

Front 26

Gastric glands of Fundus-body

Back 26

gastric pit
foveola
A gastric gland consists of three regions:

Hint 26

1. The pit, or foveola
2. the neck
3. the body