Histology

Question 1

definition of mucous membrane (tunica mucosa)

Answer 1

epithelium and the underlying loose connective tissue which may contain a tunica muscularis mucosae, covers the cavities connected to the outside of the body

Question 2

definition of a tonsil

Answer 2

lymphatic aggregation in the mucous membrane

Question 3

definition of a serous membrane (tunica serosa)

Answer 3

mesothelium and the underlying loose connective tissue, covers the closed body cavities and therefore the external surface of most of the GI tract

Question 4

composition of the mucous membrane

Answer 4

surface epithelium, lamina propria mucosae (loose CT), and muscularis mucosae (inner circular and outer longitudinal smooth muscle)

Question 5

CT comprising submucosa

Answer 5

dense irregular CT, contains glands, vessels and nerve plexuses

Question 6

composition of the serous membrane

Answer 6

lamina propria serosae (loose CT) and mesothelium (simple squamous)

Question 7

functions of the alimentary mucosa

Answer 7

1) barrier - prevent entry of bacteria and substances
2) secretion - enzymes, HCl, mucous
3) absorptive - breakdown products of the digestion
4) immunologic - lymphatic tissue serves as a first line of the immune defense

Question 8

layers of the masticatory mucosa

Answer 8

epithelium (parakeratinized), lamina propria (rests on top of periosteum/bone)

Question 9

location of masticatory mucosa

Answer 9

gingiva (gums) and hard palate

Question 10

types of mucous membrane in the oral cavity

Answer 10

masticatory mucosa, lining mucosa, and specialized mucosa

Question 11

location of the lining mucosa in the oral cavity

Answer 11

lips, cheeks, floor of the mouth, inferior surface of the tongue and soft palate

lies on the surface of skeletal muscle

Question 12

layers of the lining mucosa

Answer 12

epithelium (stratified, squamous non-keratinized), lamina propria, submucosa, striated muscle

Question 13

layers of the lining mucosa of the upper lip

Answer 13

1. pars mucosa - nonkeratinized or parakeratinized with mixed salivary glands
2. rubor labii (vermilion border) - thin keratinzed, no glands
3. pars cutanea - skin with sebaceous glands and hair follicles

Question 14

location of specialized mucosa in the oral cavity

Answer 14

dorsum of the tongue, contains papilla

Question 15

filiform papilla

Answer 15

• “flames” point backward
• found on the dorsum of the tongue
• keratinzed epithelium
• no taste buds, only mechanical function

Question 16

foliate papilla

Answer 16

• leaf shaped
• found on the lateral margins of the tongue
• slightly keratinized epithelium
• decrease with age

Question 17

circumvallate papilla

Answer 17

• dome shaped
• found at the sulcus terminalis of the tongue
• only 8-12 present
• taste buds in the side
• Von Ebner’s serous glands open into the clefts

Question 18

fungiform papilla

Answer 18

• mushroom shaped
• found on the dorsum and tip of the tongue
• slightly keratinized epithelium
• taste buds in the side

Question 19

composition and function of the intercalated duct

Answer 19

• low cuboidal epithelial cells

- secrete bicarbonate and absorb chlorine

Question 20

composition and function of the striated duct

Answer 20

• simple cuboidal epithelium that gradually becomes columnar

- reabsorption of sodium and secretion of potassium and bicarbonate

Question 21

composition and function of the excretory duct

Answer 21

• from pseudostratified columnar to stratified cuboidal and columnar
• parotid (Stensen’s duct) and submandibular (Wharton’s duct)

Question 22

characteristics of serous acinous glands

Answer 22

• small acinus and lumen
• spheroid central nucleus
• basophilic cytoplasm (rER)

Question 23

characteristics of mucous acinus glands

Answer 23

• large acinus and lumen
• flattened basal nucleus
• “empty” cytoplasm with H&E (mucous)

Question 24

serous demilune

Answer 24

serous cap on a mucous acinus and is typically found in the submandibular and sublingual glands

Question 25

epithelial tissue in the nasopharynx

Answer 25

pseudostratified respiratory epithelium with goblet cells

Question 26

epithelial tissue in the oropharynx and laryngopharynx

Answer 26

nonkeratinized stratified squamous

Question 27

location and function of the mucosal glands in the esophagus

Answer 27

- located in lamina propria at the the terminal part of the esophagus, at the esophageo-cardiac junction, and frequently at the beginning of the esophagus - produce neutral mucous lubricating the cardia to prevent pyrosis (heartburn)

Question 28

location and function of the submucosal glands in the esophagus

Answer 28

- located in the submucosa scattered along the entire esophagus - produce slightly acidic mucous lubricating the lumen

Question 29

shape of fundic glands (fundus, corpus)

Answer 29

simple, branched, tubular

Question 30

shape of pyloric glands (pylorus)

Answer 30

coiled, branched, tubular

Question 31

shape of cardiac glands (cardia)

Answer 31

similar to the pyloric glands but shorter, coiled, branched, and tubular

Question 32

fundic glands cell types

Answer 32

mucous neck cells, chief, parietal, and enteroendocrine

Question 33

location and function of mucous neck cells

Answer 33

- located at the neck of the glands | - provides soluble mucous

Question 34

location and function of chief cells

Answer 34

- mainly on the base of the glands | - secrete pepsinogen and weak lipase

Question 35

location and function of parietal cells

Answer 35

- mainly in the middle third of the glands | - secrete HCl and intrinsic factor

Question 36

location and function of enteroendocrine cells

Answer 36

- rest on the basal lamina | - produce gastrointestinal hormones

Question 37

pyloric glands

Answer 37

- located in the pyloric antrum - coiled, branched, tubular glands - cells are mainly surface mucous cells and few enteroendocrine cells, no chief or parietal cells

Question 38

cardiac glands

Answer 38

- surround the esophageal orifice - secretion protects the mucosa of the esophagus - coiled, branched, tubular but shorter than pyloric glands - cells are mainly surface mucous cells and few enteroendocrine cells, no chief or parietal cells