Gi Week 2 Objective 2

Front 1

What is the order of segments in the GI tract?

Back 1

Stomach...Duodenum...Jejunum...Ileum...Cecum...Ascending Colon...Transverse colon...Descending colon...Sigmoidal colon...Rectum...Anal canal

Front 2

What are the four basic layers common to most parts of the GI tract?

Back 2

1. mucosa
2. submucosa
3. muscularis externa
4. adventitia

Front 3

What are two cell types characteristic of gastric mucosa, what are their roles, and what do they look like?

Back 3

1. parietal cell: secrete HCl: large, rounded, central nucleus, eosinophilic cytoplasm
2. chief cell: serous secreting (pepsinogen): cuboidal/columnar, round basal nucleus, granular

Front 4

What are mucous neck cells, and where are they located?

Back 4

1. Mucous neck cells are tall columnar mucous-secreting cells (protect stomach surface with mucous)
2. They are located in the neck area of gastric glands in the stomach.

Front 5

In which area of the stomach are lymphoid nodules prominent?

Back 5

Pylorus

Front 6

What does duodenal mucosa constist of (2 things)?

Back 6

1. Villi
2. Intestinal glands/crypts (crypts of Lieberkuhn)

Front 7

What drains into the intestinal crypts of the duodenum?

Back 7

Brunner's glands (mucous secreting)

Front 8

Which part of the small intestine has the largest area for secretion and absorption?

Back 8

Jejunum

Front 9

What are the two types of cells characteristic of the jejunal epithelium?

Back 9

1. Enterocytes: tall columnar absorptive cells, basal oval nuclei, apical striated border
2. Goblet cells: washed out cytoplasm, mucin granule content

Front 10

What is in the center of jejunal villi? (4 things)

Back 10

1. Lamina propria
2. Small systemic capillaries
3. Lymphatic lacteal
4. Smooth muscle cells

Front 11

In which part of the intestine are goblet cells most prominent?

Back 11

Ileum

Front 12

What cells are at the base of ileal glands, and what do they do?

Back 12

Paneth cells: regulate bacterial microenvironment of crypts by secreting lysozyme, phagocytose bacteria and immunoglobulins

Front 13

What are plicae?

Back 13

Circular folds, characteristic of ileum.

Front 14

How long is the colon?

Back 14

1.5 meters

Front 15

Where does the colon begin and end?

Back 15

Ileo-cecal junction, recto-anal junction

Front 16

What are the four tissue layers of the colon?

Back 16

1. Mucosa
2. Submucosa
3. Muscularis
4. Serosa (NOT adventitia)

Front 17

What is the difference between serosa and adventitia?

Back 17

Serosa: thin layer of cells which excrete serous fluid to reduce friction from muscular movement (large intestine).
Adventitia: a connective tissue layer which binds together structures rather than reducing friction between them (stomach, small intestine).
(wikipedia)

Front 18

What are the three equidistant longitudinal bands of the colon?

Back 18

Taenia coli

Front 19

What are the saccules formed between the taenia coli due to their state of partial contraction?

Back 19

Haustra

Front 20

What cells are affected in ulcerative colitis?

Back 20

Paneth cells of the ileum

Front 21

In which part of the GI are lymphatic nodules prominent?

Back 21

Appendix, colon

Front 22

What parts of the GI tract lack villi?

Back 22

Stomach, appendix, colon

Front 23

What is the characteristic difference of the recto-anal junction from the rest of the colon?

Back 23

It's epithelium has more numerous goblet cells