Anatomy stomach/Intestins

Question 1

Small intestine Unique features

Answer 1

Transverse folds, called circular folds or plicae circulares, are the major gross feature of the intestinal lining

Intestinal villi are smaller finger like projections covered with simple columnar epithelium that have microvilli on their apical surface

Question 2

What are the parts of the digestive tract?

Answer 2

Digestive tract = a muscular tube for the most part, includes:
Oral cavity
Pharynx
Esophagus
Stomach
Small intestine
Large intestine

Accessory organs include:
Teeth
Tongue
Glands: salivary glands, liver, gall bladder, and pancreas

Question 3

What are the functions of the digestive system?

Answer 3

Ingestion
Mechanical processing
Digestion
Secretion
Absorption
Excretion

Question 4

Peritoneum:

Answer 4

visceral and parietal layers line the organs and walls of the abdominopelvic cavity

They reduce friction

Question 5

Mesenteries:

Answer 5

suspensive ligaments or serous membranes that connect to the two peritoneal layers to stabilize the position of organs and provide routes for blood vessels, lymphatics and nerves.

Hold organs together

Question 6

What are the mesenteris?

Answer 6

Lesser omentum – stomach

Falciform ligament – liver

Greater omentum – adipose tissue for padding (beer belly)

Mesentery proper – small intestine

Transverse and sigmoid mesocolons – large intestine

Question 7

What does retro-peritoneal mean?

Name something that is retro-peritoneal

Answer 7

Not found in the peritoneal lineing. retroperitoneal organs are covered in adventitia

Asending and descending colon

Question 8

What structures do all histology in the GI tract share?

Answer 8

Mucosa
Submucosa
muscularis
Adventitia

Question 9

Which layers are part of the mucosa?

Answer 9

epithelium, lamina propria, muscularis mucosae

Question 10

Which layors are part of the submucosa?

Answer 10

loose connective tissue containing vessels, lymphatics and nerves

Question 11

Which layors are part of the muscularis externa

(Its made of two thin layors of smooth mucle).

Answer 11

Inner circular layer

Outer longitudinal layer

Question 12

What layers are part of the Aventitia?

What type of epithilium does it have?

Answer 12

outermost layer of connective tissue

simple squamous epithelium called the mesothelium

Question 13

The Epithelium in the digestive system is determined by what?

Answer 13

varies depending on mechanical stresses of passing food:

Question 14

What parts of the digestive system have Stratified Squamous epithilium?

Simple columnar?

Answer 14

Stratified squamous in oral cavity, pharynx, esophagus

Simple columnar in stomach and small/large intestine

Question 15

What is included as part of the oral cavity?

Answer 15

Includes such organs as:
Lips
Tongue
Teeth
Salivary glands

Question 16

What are the functions of the oral cavity?

Answer 16

Ingestion
Sensory reception
Mechanical processing
Lubrication
digestion

Question 17

What type of epithilium is Oral Mucosa?

Where is it kernalized?

Answer 17

Stratified squamous epithilium.

on the tongue and hard palate

Question 18

What are the glands of the oral cavity?

Answer 18

Parotid, sublingual, sub-mandibular

Question 19

1. What does the parotid gland produce?
2. Submandibular gland?
3. Sublinqual gland?

Answer 19

1. Serous secretion and amylase to start digestion
2. Secrete mucins, and amylase
3. Mucouse secretion for buffer and lubricant

Question 20

1. Saliva is what percent water?

2. What else is in saliva?

Answer 20

1. 99.4%

2. Na, Cl, HCO3, buffers, glycoproteins (mucins) enzymes (amylase, lysozyme), antibodies and waste products

Question 21

What are the functions of saliva?

(note Neuronal control via salivatory nuclei in medulla
stimulated by CN V or taste buds which stimulate CN VII, IX and X
Parasympathetic stimulation increases output)

Answer 21

Lubricate oral surfaces,
Moisten food,
Dissolve chemicals to stimulate taste buds,
Start digestion of carbohydrates,
pH buffering,
Bacterial control

Question 22

What are the tonsillar tissues in the pharynx?

Where are they located?

Answer 22

Lingual tonsil
Palatine tonsils
Pharyngeal tonsil

pharynx

Question 23

What are the pharyngeal constrictor muscles?

Answer 23

Crocopharyngeus
Inferior pharyngeal constrictor
Middle pharyngeal constrictor
Superior pharyngeal constrictor

Question 24

What are the phases of swallowing?

What happens during them?

Answer 24

Buccal phase – compression and propulsion toward oropharynx

Pharyngeal phase – elevation of larynx
Epiglottis guards opening to trachea
Uvula and soft palate block opening to nasopharynx

Esophageal phase – contraction of pharyngeal constrictors and peristalsis along esophagus

Stomach entrance – approaching bolus triggers relaxation of lower esophageal (cardiac) sphincter

Question 25

What is perisalsis?

Answer 25

Peristalsis is different from segmentation that occurs in small and large intestine

Wavelike sequential contraction

Question 26

Which cranial nerves provide sensory information to salivatory nuclei

Answer 26

5,7,9,10

Question 27

How many permanent teeth in the normal adult?

Answer 27

32

Question 28

What are the steps in peristalsis

Answer 28

Steps
1. circular muscles behind bolus contract

2. longitudnal mucles ahead of bolus contract(appear to open)

3 contraction in circular muscle forces bolus forward.