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Flashcards in Histology Intestines Deck (38)
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1
Q

Shortest and widest part of small intestine?

A

Duodenum

2
Q

Principle site for digestion of food?

A

Small intestine

  • absorption here
  • synthesis and secretion of digestive enzymes
  • control microbial growth
3
Q

Small intestine regulates GI function via the ____ secretion by ____ cells.

A

Endocrine secretion by enteroendocrine cells

4
Q

Unique feature of the small intestine? What do they contain?

A

Presence of place circulares- permanent transverse folds that contain a core of submucosa

Contain both mucosa and submucosa

5
Q

Plicae are most numerous in the _____ and _____ and increase the surface for absorption.

A

Distal duodenum and proximal jejunum

6
Q

Most unique feature of the mucosa of the small intestine is the presence of what?

A

Villi

7
Q

The core of the villus is formed by ______ of the _____.

A

Loose CT of the lamina propria

NO submucosa in the villus

8
Q

Enterocytes are responsible for the _____ of ____ and produce _____.

A

Absorption of nutrients and produce digestive enzymes

9
Q

Where does the final stage of digestion of carbohydrates and proteins occur?

A

Glycocalyx of the intestinal absorptive cells

10
Q

Lipids are broken down into monoglycerides and fatty acids within the _____. They diffuse across the ______ and are resynthesized into triglycerides in the _____ of the ______. Fat droplets are then transported to the ____ where they acquire a protein coat and become ______. They then bud and are transported to eh basolateral surface of the absorptive cell where they are released into the _____.

A
Lumen of the intestine
Absorptive cell membranes 
Smooth ER 
Intestinal absorptive cell
Golgi apparatus 
Chylomicra
Extracellular space
11
Q

Enterocytes are also involved in transcytosis of ___ from the lamina propria of the intestinal lumen. What is this synthesized by? What does it protect and regulate?

A

IgA
Synthesized and secreted by plasma cells in lamina propria
Protect mucosa by regulating microbial growth

12
Q

Enterocytes contain what on the apical surface? What are they bounded by?

A

Microvilli

Tight and anchoring junctions

13
Q

Narrow base, wide apex, mucinogen granules, small triangular and heterochromatic nucleus that is nasally placed

A

Goblet cells

14
Q

Found in the epithelium overlying lymphoid follicles

A

M-cells

15
Q

M-cells are ____ cells. They convey microorganisms and other macromolecules from the epithelial lumen to the ____.

A

Antigen-transporting

Lymphoid follicles

16
Q

Large, dome-shaped cells, filled with macrophages, dendritic cells, and lymphocytes. Covered by microfolds.

A

M-cells

17
Q

Unusual type of T-lymphocytes. Blood-derived. Involved in providing mucosal immunity.

A

Intraepithelial lymphocytes

18
Q

What two cell types are foun dint he crypts of Lieberkuhn but not the surface epithelium?

A

Paneth cells and progenitor cells

19
Q

What is found at the bottom of the crypts of Lieberkuhn?

A

Paneth cells- regulate normal bacterial growth

20
Q

Most prominent feature of Paneth cells?

A

Numerous large, refractive eosinophilic granules int he apical portion of the cell

  • granules contain antibacterial enzyme lysozyme, alpha defensins
  • basal part of cell has well-developed RER
21
Q

Large associations of lymphoid follicles are found where? What are they called? What do they contain?

A

Ileum, called Peyer’s patches

Consists mainly of M-cells

22
Q

Blood supply to lamina propria consists of ____ that begin from the arteriolar of the submucosal vascular plexus and return to the venues of the same plexus. What is transported by blood vessels? What isn’t?

A

Capillary loops

Soluble nutrients unlike chylomicra

23
Q

Each villus contains a central blind-ended lymphatic capillary called a ____. These drain into large lymphatic vessels within the ____. What do they transport?

A

Lacteal

Submucosa

Transport lipids in the form of chylomicra produced by enterocytes

24
Q

Submucosa of the small intestine is typical for the rest of the alimentary canal and consists of _____ and the ___ plexus.

A

Dense CT

Vascular and nerve- Meissner’s

25
Q

Mucous-producing branched tubular glands most abundant in the proximal part of the duodenum. Purpose?

A

Brunner’s glands- neutralize acid-containing chyme

26
Q

Where is the Auerbach’s plexus found?

A

Muscularis externa between the inner circular and outer longitudinal layer

27
Q

Adventitia or serosa?

Duodenum

Jejunum

Ileum

A

Duodenum- mostly adventitia, some serosa

Jejunum and ileum- serosa

28
Q

Features of duodenum

A

Submucosa Brunner’s glands

Least amt of goblet cells

29
Q

Features of jejunum

A

Tallest villi and most prominent lacteals

More of a rule out

30
Q

Features of the ileum

A

Peyer’s patches, highest concentration of goblet cells

Villi are shorter

31
Q

Principal function of the large intestine?

A

Reabsorption of electrolytes and water AND elimination of undigested food and waste

32
Q

How is the mucosa of the large intestine different?

A

No villi, no paneth cells

More abundant goblet cells

33
Q

What is foun dint he deeper parts o the crypts of Lieberkuhn in the large intestine?

A

Progenitor cells

34
Q

In the muscularis externa of the large intestine, the other longitudinal muscle layer forms three thickened equally spaced bands called what?

A

Teniae coli

35
Q

The ___ of the large intestine contains small fatty projections called the _____ which are visible on the outer intestinal surface.

A

Serosa

Omental appendices

36
Q

Taeniae coli is absent from what two things?

A

Appendix and rectum

37
Q

What contains a large number of aggregated lymphatic follicles?

A

Vermiform appendix

38
Q

Rectum contains prominent folds called what?

A

Transverse rectal folds