Test 3 Histology Gi System 3

Front 1

What is the equivalent of rugae in the small intestine?

Back 1

Plicae Circulares

Front 2

What are Plicae Surculares and what is their function?

Back 2

They are like rugae but in the small intestine. They help increase surface area for absorption.

Front 3

What are the 3 morphological adaptations in the gut tube that increase surface area?

Back 3

Plicae Circulares
Villi
Microvilli

Front 4

What makes up the core tissue of the Plicae Circulares?

Back 4

Submucosa

Front 5

What are the main layers that make up the small intestine?

Back 5

Serosa
Muscularis Externa
Submucosa
Mucosa

Front 6

What are the folds in the mucosa of the small intestine called?

Back 6

Villi

Front 7

Villi in the small intestine are finger-like projections containing a core of ____ and covered with ____.

Back 7

Lamina Propria
Epithelium

Front 8

What structures make up the core of a villus?

Back 8

Connective Tissue
Smooth Muscle
Capillary Network
Lacteal (Lymphatic)

Front 9

What epithelium covers the surface of the small intestine?

Back 9

Simple Columnar

Front 10

What type of simple columnar epithelium cells make up the lining of the small intestine?

Back 10

1. Enterocytes
2. Goblet Cells
3. Antigen Presenting M-cells

Front 11

What is an enterocyte and what structure do these have?

Back 11

Absorptive cells of the lining of the small intestine.
These have a microvilli brush border.

Front 12

What is the function of Goblet cells in the small intestine?

Back 12

Secrete mucous that helps protect the lining of the intestine from pancreatic enzymes and bacteria increase.

Front 13

What is the function of antigen presenting M Cells? Where would you find these?

Back 13

They take antigens from the lumen by phagocytosis and present them to lymphocytes scattered throughout the mucosa.
Found scattered throughout the epithelium of the small intestine.

Front 14

Where would you find a Crypt of Lieberkuhn?

Back 14

Small and Large Intestines.
Between the villi.

Front 15

What are the cell types in the Crypts of Lieberkuhn?

Back 15

1. Undifferentiated stem cells
2. Enteroendocrine cells
3. Paneth cells

Front 16

Crypt of Lieberkuhn:
Where are the Undifferentiated stem cells found? What do they give rise to?

Back 16

Found in the lower half of the crypt.
Give rise to absorptive cells (enterocytes), goblet cells, and enteroendocrine cells.

Front 17

What are the products of the enteroendocrine cells located in the Crypts of Lieberkuhn?

Back 17

1. Secretin
2. Cholecystokinin
3. Gastric Inhibitory Peptide
4. Motilin

Front 18

What is the function of secretin? What kind of cells secrete it in the small intestine?

Back 18

Stimulates growth and secretion of the exocrine pancreas.
Enteroendocrine cells of the Crypts of Lieberkuhn.

Front 19

What is the function of Cholecystokinin (CCK)?
Where in the small intestine is it secreted?

Back 19

Stimulates growth and secretion of the exocrine pancreas AND contraction of the smooth muscle of the gall bladder. Also INHIBITS gastric emptying.
Secreted from the enteroendocrine glands of the Crypts of Lieberkuhn.

Front 20

What is the function of Gastric Inhibitory Peptide (GIP)?
Where in the small intestine is GIP secreted?

Back 20

Inhibits HCl secretion by the parietal cells of the stomach.
Secreted by the enteroendocrine cells of the Crypts of Lieberkuhn.

Front 21

What do paneth cells do?
Where are they found?

Back 21

Secrete the antibacterial enzyme lysozyme.
Found in the base of the Crypts of Lieberkuhn.

Front 22

What is the structure of the muscularis mucosa of the small intestine?
What does this layer help the small intestine to do?

Back 22

Usual inner circular and outer longitudinal smooth muscle.
Strands of smooth muscle from this layer extend up into the villi, causing their movement and aiding the circulation of lymph through the lymphatic vessels.

Front 23

What special structures are found in the Submucosa of the duodenum? the ileum? throughout the small intestine?

Back 23

Brunner's Glands
Peyer's Patches
Meissner's Plexus

Front 24

What do Brunner's Glands do?
Where are they found?

Back 24

Secrete alkaline mucus that protects the mucosa from acid and raises the pH for pancreatic enzyme activity.
Found in the Submucosa of the Duodenum.

Front 25

What are Peyer's Patches?

Back 25

Patches of lymphoid tissue found in the submucosa of the ileum.

Front 26

What are the 3 sections of the small intestine from top to bottom?

Back 26

duodenum
jejunum
ileum

Front 27

What is the function of the Muscularis Externa in the small intestine?

Back 27

Peristalsis

Front 28

What plexus is found between the two layers of the Muscularis Externa?

Back 28

Auerbach's Plexus

Front 29

What are the parts of the large intestine from start to finish?

Back 29

Cecum
Vermiform Appendix
Ascending Colon
Transverse Colon
Descending Colon
Rectum
Anal Canal

Front 30

What are the main functions of the colon and rectum?

Back 30

Absorption of water and electrolytes.
Compaction and elimination of undigested food.

Front 31

What valve is located between the small and large intestine?

Back 31

Iliocecal Valve

Front 32

What is the structure of the Iliocecal Valve?

Back 32

It consists of two horizontal folds of mucous membrane that project around the orifice of the ileum.

Front 33

What controls the flow of contents from the ileum into the colon?

Back 33

The circular muscle (Iliocecal Sphincter) of the lower end of the ileum controls the flow of contents.

Front 34

In what way is the Mucosa of the Colon similar to that of the small intestine? (What cell types do they share?)

Back 34

Both have Simple Columnar Epithelium cells, Goblet Cells and M cells.
Lamina Propria with Crypts of Lieberkuhn and lymphatic tissue.
Muscularis Mucosa.

Front 35

In what ways does the Mucosa of the Colon differ from that of the small intestine?

Back 35

No Villi!
No Paneth Cells!

Front 36

The mucosa of the colon is ____ than the mucosa of the small intestine.
It also has more ____ cells.

Back 36

Thicker
Goblet

Front 37

In what layer of the colon would you find the Meissner's Plexus?

Back 37

Submucosa

Front 38

What is the location of the hemorrhoidal plexus of veins in the colon?

Back 38

Lower rectum
Located in the Submucosa and extending into the lamina propria.
(These veins have no valves. There may also by lymphatic nodules present in this area.)

Front 39

What is the arrangement of the Muscularis Externa in the Colon?

Back 39

The outer longitudinal layer is arranged into 3 thick bands called the Teniae Coli.

Front 40

What are Teniae Coli?

Back 40

3 thick bands of outer longitudinal muscle in the colon.

Front 41

How do the Teniae Coli work?

Back 41

They are shorter than the colon so they gather its wall into sacculations called haustra.

Front 42

What plexus is located between the layers of the Muscularis Externa in the Colon?

Back 42

Auerbach's Plexus

Front 43

Hirschsprung's Disease (Congenital Megacolon)
What causes it?
What happens?

Back 43

Caused by an absence of ganglion cells in the Meissner's and Auerback's Plexuses of the rectum.
Feces remain in the colon causing it to enlarge.

Front 44

How can you tell the Vermiform Appendix from the Colon?

Back 44

It is similar in structure but it has shorter Crypts of Lieberkuhn and NO TENIAE COLI.

Front 45

The Lamina Propria and Submucosa of the Vermiform Appendix contain large amounts of _____ tissue.

Back 45

Lymphoid Tissue

Front 46

Anal Canal:
The epithelium is ____. The lamina propria contains ____ crypts.

Back 46

Simple Columnar
Short Crypts

Front 47

What is this structure?
What glands can be seen?

Back 47

Duodenum
Brunner's Glands (secrete alkaline mucous)

Front 48

What is this structure?

Back 48

Jejunum
(Looks a lot like ileum BUT-
longer, more slender villi, and no Peyer's Patches)

Front 49

What is this structure?
What are the basophilic blobs?

Back 49

Ileum
Peyer's Patches

Front 50

What is this structure?
What are the basophilic blobs?

Back 50

Ileum
Peyer's Patches

Front 51

What are the basophilic structures?
Where are these found?

Back 51

Peyer's Patches
Ileum

Front 52

What cell type is shown?
Where are these found?

Back 52

Paneth Cells
Located at the base of Crypts of Lieberkuhn

Front 53

What is this structure?

Back 53

Colon (Notice Teniae Coli)

Front 54

What are the circled structures?
What layer are these in?

Back 54

Crypts of Lieberkuhn (in colon here)
Lamina Propria

Front 55

What is this structure?

Back 55

Appendix

Front 56

What is this?
(What other structures are taggable here?)

Back 56

Anal Canal
(Hair and Apocrine Glands)

Front 57

What are the arrows pointing to?

Back 57

Auerbach's Plexus
(Between layers of Muscularis Externa)

Front 58

What structure is circled?
What layer is this?

Back 58

Meissner's Plexus
Submucosal Layer

Front 59

What cells are the arrows pointing to?

Back 59

Goblet Cells

Front 60

What are the main layers of the anal canal?

Back 60

Mucosa
Submucosa
Muscularis Externa
ADVENTITIA

Front 61

What kind of epithelium makes up the mucosa of the upper and lower halves of the anal canal?

Back 61

Upper half= Simple Columnar
Lower half= Stratified squamous nonkeratinized

Front 62

Does the lamina propria in the anal canal have Crypts of Lieberkuhn?

Back 62

No.

Front 63

The submucosa of the anal canal contains _____ glands associated with hair and ____ sweat glands.

Back 63

Sebaceous
Apocrine

Front 64

What muscle layer makes up the involuntary internal anal sphincter?

Back 64

Made of the inner circular layer of smooth muscle of the Muscularis Externa
(In the upper 3/4 of the canal)

Front 65

What muscle forms the voluntary external anal sphincter?

Back 65

Skeletal muscle from the pelvic diaphragm (the muscular floor holding important organs in place.)