8: Histology

Question 1

What kind of epithelium is found in the oral cavity, oropharynx and laryngopharynx?

Answer 1

Stratified squamous epithelium

Question 2

Which kind of epithelium is found in the nasal cavity and nasopharynx?

Answer 2

Ciliated, pseudostratified, columnar epithelium with goblet cells

i.e respiratory epithelium

Question 3

What is the ventral surface of the tongue?

Answer 3

Underside of the tongue

Question 4

What is the dorsal surface of the tongue?

Answer 4

Top

Question 5

Name the four kinds of papillae found on the tongue.

Answer 5

Fungiform

Circumvallate

Filiform

Foliate

Question 6

Which papillae aren’t tastebuds and instead aid in the manipulation of food around the mouth?

Answer 6

Filiform papillae

Question 7

What is found in the submucosa of the oesophageal lining?

Answer 7

Submucosal glands

Question 8

In which two parts of the GI tract are glands submucosal?

Answer 8

Oesophagus

Duodenum

Question 9

What is the gastro-oesophageal junction also known as?

Answer 9

Z line

Question 10

What is the epithelial transition at the gastro-oesophageal junction / Z line?

Answer 10

Stratified squamous epithelium

to

Columnar epithelium

Question 11

What is found in the mucosa of stomach cells?

Answer 11

Gastric pits

which contain gastric glands

Question 12

What are found in the gastric pits of stomach cells?

Answer 12

Gastric glands

Question 13

Give two examples of cells found in the gastric pits?

Answer 13

Parietal cells

Chief cells

Question 14

What do parietal cells secrete?

Answer 14

Intrinsic factor (for Vitamin B12)

Hydrochloric acid

Question 15

What do Chief cells secrete?

Answer 15

Pepsinogen (precursor of pepsin, a digestive enzyme)

Question 16

What is unusual about the muscularis externa of stomach cells?

Answer 16

It has an additional layer of muscle

probably for mixing and churning food

Question 17

At the ___ ___, the smooth muscle thickness of the muscularis externa increases.

Answer 17

pyloric sphincter

Question 18

What are the finger-like projections found on the mucosa of small intestinal surfaces?

Answer 18

Villi

Question 19

What is the proper name for the pits found next to villi on the small intestinal mucosa?

Answer 19

Crypts of Lieberkuhn

Question 20

What are enterocytes?

Answer 20

Main absorptive cells of the small intestine

tall, columnar and with brush borders

Question 21

What are goblet cells?

What do they produce?

What does this substance do?

Answer 21

Small intestinal glands

Mucin

Protects and lubricates cells; move things along

Question 22

Where are paneth cells found?

What is their function?

Answer 22

Bottom of Crypts of Lieberkuhn

Antibacterial

Question 23

What cells produce hormones to control gastric secretion and motility?

Answer 23

Enteroendocrine cells

Question 24

Give two examples of hormones secreted by enteroendocrine cells.

Answer 24

CCK, VIP, Gastrin

Question 25

What cells, found in the **Crypts of Lieberkuhn**, divide to replenish the epithelium?

Answer 25

**Stem cells**

Question 26

Where in the small intestine are **Brunner's glands** found?

Answer 26

**Duodenum**

Question 27

What is the function of **Brunner's glands**?

Answer 27

Release **alkaline mucous** (bicarbonate?) to neutralise HCl in chyme remember that bile is alkaline

Question 28

Where in the small intestine are the **tallest villi** found?

Answer 28

**Jejunum**

Question 29

Which folds, found in the **jejunum**, allow the villi to be tall and prominent?

Answer 29

**Plicae circularis** big folds

Question 30

What lymphoid tissue is found in the **ileum**?

Answer 30

**Peyer's patches**

Question 31

In the **large intestine** only, the **longitudinal muscle** of the **muscularis externa** is split into **three** layers - what are these layers called?

Answer 31

**Teniae coli** **so:** Mucosa (epithelium, lamina propria, muscularis mucosae) Submucosa (w/ glands sometimes) Muscularis externa (circular, longitudinal (teniae coli)) Serosa

Question 32

The **teniae coli** are found in the **(circular / longitudinal)** muscle layer of **(small intestine / large intestine)**.

Answer 32

**longitudinal** **large intestine**

Question 33

Which offshoot of the caecum has a lot of **lymphoid tissue**?

Answer 33

**Appendix**

Question 34

\_\_\_ tissue in the **appendix** declines with \_\_\_.

Answer 34

**Lymphoid** **age**

Question 35

Which nervous system is found within the digestive tract?

Answer 35

**Enteric nervous system**

Question 36

What are the **two** nerve plexuses visible in GI tract tissue?

Answer 36

**Submucosal plexus** (in the submucosa) **Myenteric plexus** (between the circular and longitudinal muscle of muscularis externa)

Question 37

In which layer is the **myenteric plexus** visible?

Answer 37

**Muscularis externa**

Question 38

In which layer is the **submucosal plexus** visible?

Answer 38

**Submucosa**

Question 39

oxyntic cells are "pink fried eggs with purple yolks" slide 19

Question 40

large intestinal crypts "like test tubes in a rack"