L22 Abdominal wall, Oral cavity and Organs of digestion Part 2

Hard Palate

• Made of the maxilla and palatine bones.

Soft Palate

Muscular mucosa containing the uvula (closes nasopharynx), palatoglossal arch, and palatopharyngeal arch (with the palatine tonsil between them).

Palatoglossal arch

• Mucus membrane containing muscle that runs from the soft palate to the sides of the tongue and assists in elevating the tongue and aids in swallowing. 

Palatopharyngeal arch:

• Elevates pharynx/larynx for swallowing + airway protection.

What are the boundaries of the oral cavity?

Teeth (front), oropharynx (back), palate (top), tongue/floor (bottom).

What is the tongue made of and what does it do?

Skeletal muscle; moves and manipulates food.

Types of papillae?

Vallate (taste), fungiform (taste), filiform (no taste, grip).

What do teeth do?

Mechanical digestion (break food down).

Types of teeth + function?

-Incisors (cut)

-canines (tear)

-molars (grind).

Function of salivary glands?

Moisten food + start carb digestion

3 major salivary glands?

-Parotid

-sublingual

- submandibular.

What are the 3 phases of swallowing?

Voluntary → pharyngeal → esophageal

What happens in the pharyngeal phase?

Airway closes (uvula + epiglottis).

Function of esophagus?

Moves food to stomach via peristalsis

Muscle types in esophagus?

Upper = skeletal, lower = smooth.

What is the stomach’s main function?

Mix and chemically digest food.

Where is the stomach located?

Left Upper Quadrant (LUQ).

4 parts of the stomach?

Cardia, fundus, body, pylorus.

What is the greater omentum?

Fatty apron covering abdominal organs.

What are rugae?

Folds that allow the stomach to expand.

What do mucus neck cells do?

Protect stomach lining.

What do chief cells do?

Release pepsin (proteins) + lipase (fats).

What do parietal cells do?

Secrete HCl + intrinsic factor (B12).

What do enteroendocrine cells do?

Release gastrin.

How does food leave the stomach?

Through pyloric sphincter → small intestine

Main function of small intestine?

Nutrient absorption.

3 parts of small intestine?

-Duodenum

-jejunum

-ileum

Which part is retroperitoneal?

Duodenum.

Which parts are intraperitoneal?

Jejunum and ileum.

Structures that increase absorption?

Plicae circulares, villi, microvilli.

What do capillaries absorb?

Carbs and proteins.

What do lacteals absorb?

Fats

What do enterocytes do?

Absorb nutrients.

What do goblet cells do?

Secrete mucus.

Key hormones of enteroendocrine cells?

CCK, secretin, GIP.

What do submucosal glands do?

Neutralize acid with bicarbonate.

What are Peyer’s patches?

Lymphatic tissue for immune defense.