Chapter 7: Small Intestine - Anal Canal Flashcards Preview

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Flashcards in Chapter 7: Small Intestine - Anal Canal Deck (65)
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1
Q

What are 3 general functions of the SI?

A
  1. Digestion
  2. Absorb Nutrients
  3. Produce Intestinal Hormones using DNES cells
2
Q

IC: What are lacteals? Where are they found?

A

Lymphatic capillaries

Found in LP of SI villi

3
Q

IC: Where are paneth cells found and what do they do?

A

Bases of crypts

produce lysozyme

4
Q

IC: Where are Brunner’s Glands found? What do they do and why?

A

SM of duodenum

Secrete alkaline mucus to neutralize chyme

5
Q

What 3 surface adaptations increase surface area by 400+?

A

Plicae Circulares (valves of Kerckring)

Villi

Microvilli (on luminal cell surface)

6
Q

What permanent folds affecting the mucosa and submucosa are found in the duodenum, jejunum, and proximal ileum?

A

Plicae Circulares (valves of Kerckring)

7
Q

What is the surface epithelium of the intestinal mucosa?

A

Simple columnar

8
Q

What surface absorptive cells are found in the mucosa? What are their 2 main functions?

A

Enterocytes (with microvilli)

Fxns:

  1. Absorb water and nutrients
  2. Terminal digestion in glycocalyx (enterocytes produce the enzymes & absorb the monosaccharides and peptides created)
9
Q

Where are goblet cells located in the SI?

A

Most in Ileum

Fewest in duodenum

10
Q

How many types of DNES cells are found in the SI?

A

11

11
Q

One DNES cell produces CCK… how does that effect the SI?

A

Stimulates gallbladder contraction & pancreatic secretion of enzymes from serous acini

12
Q

One DNES cell produces GIP… how does that effect the SI?

A

Inhibits HCL release

13
Q

One DNES cell produces secretin… how does that effect the SI?

A

Stimulates pancreas secretion of bicarbonate from the pancreatic ducts

Inhibits HCL release and the movement of chyme into small intestines.

14
Q

What cells are found in the crypts of the SI?

A

Regenerative cells

15
Q

Which cells are found at the base of the crypts of the SI? What is their function?

A

The long lived Paneth Cells - produce lysozyme

16
Q

Where are M (microfold) cells located?

A

Ileum epithelium over Peyer’s Patches

17
Q

IC: Name the surface epithelium lining the appendix.

A

Simple columnar

18
Q

IC: Haustra in the ME of the colon form sacculations due to what?

A

Constant tonus of teniae coli (outer longitudinal muscle)

19
Q

IC: Name the surface epithelium of the colon.

A

Simple columnar

20
Q

IC: Name the extra thick outer longitudinal ms. layer in the colon?

A

Teniae coli

21
Q

IC: Does the colon have villi? Crypts? Paneths?

A

No
Yes
No

22
Q

Which cells contain large intracellular pockets that are fairly open to the LP?

A

M cells

23
Q

What is the function of M cells?

A

Promote humoral immunity - plasma cells produce IgA which is transferred to enterocytes and released into gut lumen

24
Q

Why are M cells important?

A

Maintain gut flora

25
Q

What makes up the LP of the SI?

A

Loose areolar ct

26
Q

What are the lymphatic capillaries found in the villus core?

A

Lacteals

27
Q

What is the function of lacteals?

A

Lipid absorption

28
Q

What is found in the villus core?

A

Lacteals
Vascular components (blood capillaries)
Longitudinal smooth muscle

29
Q

How is the longitudinal smooth muscle of the LP affected if irritated?

A

The muscle will contract and the villus will shorten; can lead to nutritional deficiencies.

30
Q

What does the LP of the SI border?

A

Intestinal glands (crypts of Lieberkuhn)

31
Q

What connects to the MM of the SI?

A

The MM is thin but present

Connects to smooth muscle in villi

32
Q

What kind of tissue makes up the Submucosa of the SI?

A

Dense fibroelastic ct with large blood vessels (highly vascular)

33
Q

What are the glands found in the Duodenum?

A

Duodenal (Brunner) Glands - seromucous

34
Q

What do Brunner Glands produce?

A

Alkaline Mucous (primary product; neutralizes chyme)

Urogastrone - inhibits HCL secretion; increases mitosis of epithelial cells

35
Q

Where are Peyer’s Patches located?

A

Ileum

36
Q

What are Peyer’s Patches?

A

Large lymph nodes

37
Q

What is the function of Meissner’s Plexus?

A

Influences mucosa via parasympathetic innervations

38
Q

What is the location of Meissner’s Plexus?

A

Close to the circular muscle in the ME (Ileum)

39
Q

What is the function of the myenteric plexus?

A

Stimulates peristalsis in the ME

40
Q

Where is the Auerbach Plexus found?

A

Between the circular & longitudinal layers of ME

41
Q

Which parts of the SI contain serosa?

A

All of jejunum and Ileum

First and last 1-2 cm of duodenum

42
Q

Which parts of the SI contain adventitia?

A

Descending (vertical) part of duodenum

43
Q

T/F: The duodenum has both adventitia and serosa.

A

True

44
Q

Where is the ileocecal valve?

A

Between the ileum and the cecum of the colon

45
Q

What valve in the human body is a physiological and anatomical sphincter?

A

Ileocecal valve

46
Q

What is the surface epithelium of the mucosa of the Appendix?

A

Simple columnar with surface absorptive cells, goblets, DNES, and regenerative cells

47
Q

What is the MM of the appendix like?

A

Poorly developed

48
Q

What special features does the Mucosa of the Appendix lack?

A

Paneth cells

Villi

49
Q

What are the crypts like of the Appendix?

A

Short

50
Q

What is the submucosa of the appendix like?

A

Thick with large blood vessels

51
Q

What notable structures are found in the appendix?

A

numerous lymph nodules

52
Q

T/F: The ME of the appendix is a normal pattern, but thick.

A

False - thin

53
Q

What are the two functions of the appendix?

A
  1. Humoral immunity

2. Reservoir for good bacteria

54
Q

What 4 parts make up the LI?

A

Cecum, colon, rectum, anus

55
Q

What 4 parts make up the colon?

A

Ascending, Transverse, Descending, Sigmoid

56
Q

What is the primary function of the colon?

A

Absorption of water

57
Q

What are additional functions of the colon?

A

Compaction, lubrication, and elimination of feces

Vitamin production (B12, riboflavin, thiamin, K) as bacterial byproducts

58
Q

What is the surface epithelium of the colon?

A

Simple columnar with many goblets and colonocytes, some regenerative cells, few DNES

59
Q

What is the LP of the colon like?

A

Typical with intestinal glands (crypts)

60
Q

What is lacking in the mucosa of the colon?

A

Villi

Paneth cells

61
Q

T/F: The ME of the colon is a normal pattern.

A

FALSE

62
Q

What 2 structures are unique to the colon?

A
  1. Teniae coli - outer longitudinal muscle that is gathered into discontinuous bands
  2. Haustra - sacculations formed by constant tonus of teniae coli
63
Q

Does the colon have both adventitia and serosa?

A

Yes, it’s mixed

64
Q

What’s present in the ascending and descending colon?

A

Adventitia posteriorly with some serosa

65
Q

What’s present in the transverse and sigmoid colon?

A

Mostly serosa