Chapter 7: Small Intestine - Anal Canal

Question 1

What are 3 general functions of the SI?

Answer 1

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

Question 2

IC: What are lacteals? Where are they found?

Answer 2

Lymphatic capillaries

Found in LP of SI villi

Question 3

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

Answer 3

Bases of crypts

produce lysozyme

Question 4

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

Answer 4

SM of duodenum

Secrete alkaline mucus to neutralize chyme

Question 5

What 3 surface adaptations increase surface area by 400+?

Answer 5

Plicae Circulares (valves of Kerckring)

Villi

Microvilli (on luminal cell surface)

Question 6

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

Answer 6

Plicae Circulares (valves of Kerckring)

Question 7

What is the surface epithelium of the intestinal mucosa?

Answer 7

Simple columnar

Question 8

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

Answer 8

Enterocytes (with microvilli)

Fxns:

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

Question 9

Where are goblet cells located in the SI?

Answer 9

Most in Ileum

Fewest in duodenum

Question 10

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

Answer 10

11

Question 11

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

Answer 11

Stimulates gallbladder contraction & pancreatic secretion of enzymes from serous acini

Question 12

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

Answer 12

Inhibits HCL release

Question 13

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

Answer 13

Stimulates pancreas secretion of bicarbonate from the pancreatic ducts

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

Question 14

What cells are found in the crypts of the SI?

Answer 14

Regenerative cells

Question 15

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

Answer 15

The long lived Paneth Cells - produce lysozyme

Question 16

Where are M (microfold) cells located?

Answer 16

Ileum epithelium over Peyer’s Patches

Question 17

IC: Name the surface epithelium lining the appendix.

Answer 17

Simple columnar

Question 18

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

Answer 18

Constant tonus of teniae coli (outer longitudinal muscle)

Question 19

IC: Name the surface epithelium of the colon.

Answer 19

Simple columnar

Question 20

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

Answer 20

Teniae coli

Question 21

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

Answer 21

No
Yes
No

Question 22

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

Answer 22

M cells

Question 23

What is the function of M cells?

Answer 23

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

Question 24

Why are M cells important?

Answer 24

Maintain gut flora

Question 25

What makes up the LP of the SI?

Answer 25

Loose areolar ct

Question 26

What are the lymphatic capillaries found in the villus core?

Answer 26

Lacteals

Question 27

What is the function of lacteals?

Answer 27

Lipid absorption

Question 28

What is found in the villus core?

Answer 28

Lacteals Vascular components (blood capillaries) Longitudinal smooth muscle

Question 29

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

Answer 29

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

Question 30

What does the LP of the SI border?

Answer 30

Intestinal glands (crypts of Lieberkuhn)

Question 31

What connects to the MM of the SI?

Answer 31

The MM is thin but present Connects to smooth muscle in villi

Question 32

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

Answer 32

Dense fibroelastic ct with large blood vessels (highly vascular)

Question 33

What are the glands found in the Duodenum?

Answer 33

Duodenal (Brunner) Glands - seromucous

Question 34

What do Brunner Glands produce?

Answer 34

Alkaline Mucous (primary product; neutralizes chyme) Urogastrone - inhibits HCL secretion; increases mitosis of epithelial cells

Question 35

Where are Peyer's Patches located?

Answer 35

Ileum

Question 36

What are Peyer's Patches?

Answer 36

Large lymph nodes

Question 37

What is the function of Meissner's Plexus?

Answer 37

Influences mucosa via parasympathetic innervations

Question 38

What is the location of Meissner's Plexus?

Answer 38

Close to the circular muscle in the ME (Ileum)

Question 39

What is the function of the myenteric plexus?

Answer 39

Stimulates peristalsis in the ME

Question 40

Where is the Auerbach Plexus found?

Answer 40

Between the circular & longitudinal layers of ME

Question 41

Which parts of the SI contain serosa?

Answer 41

All of jejunum and Ileum First and last 1-2 cm of duodenum

Question 42

Which parts of the SI contain adventitia?

Answer 42

Descending (vertical) part of duodenum

Question 43

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

Answer 43

True

Question 44

Where is the ileocecal valve?

Answer 44

Between the ileum and the cecum of the colon

Question 45

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

Answer 45

Ileocecal valve

Question 46

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

Answer 46

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

Question 47

What is the MM of the appendix like?

Answer 47

Poorly developed

Question 48

What special features does the Mucosa of the Appendix lack?

Answer 48

Paneth cells | Villi

Question 49

What are the crypts like of the Appendix?

Answer 49

Short

Question 50

What is the submucosa of the appendix like?

Answer 50

Thick with large blood vessels

Question 51

What notable structures are found in the appendix?

Answer 51

numerous lymph nodules

Question 52

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

Answer 52

False - thin

Question 53

What are the two functions of the appendix?

Answer 53

1. Humoral immunity | 2. Reservoir for good bacteria

Question 54

What 4 parts make up the LI?

Answer 54

Cecum, colon, rectum, anus

Question 55

What 4 parts make up the colon?

Answer 55

Ascending, Transverse, Descending, Sigmoid

Question 56

What is the primary function of the colon?

Answer 56

Absorption of water

Question 57

What are additional functions of the colon?

Answer 57

Compaction, lubrication, and elimination of feces Vitamin production (B12, riboflavin, thiamin, K) as bacterial byproducts

Question 58

What is the surface epithelium of the colon?

Answer 58

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

Question 59

What is the LP of the colon like?

Answer 59

Typical with intestinal glands (crypts)

Question 60

What is lacking in the mucosa of the colon?

Answer 60

Villi Paneth cells

Question 61

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

Answer 61

FALSE

Question 62

What 2 structures are unique to the colon?

Answer 62

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

Question 63

Does the colon have both adventitia and serosa?

Answer 63

Yes, it's mixed

Question 64

What's present in the ascending and descending colon?

Answer 64

Adventitia posteriorly with some serosa

Question 65

What's present in the transverse and sigmoid colon?

Answer 65

Mostly serosa