GI 02: Oral Cavity + Esophagus

What are the three types of salivary glands and what are their secretions

1) Parotid —> Protein Components (Enzymes)

2) Submandibular —> Primarily mucous

3) Sublingual —> Mixture of both

What are the contents of saliva

1) ____

2) Ions (5)

3) Proteins (4)

4) ____ and ____ lipase

• Water

• Ions (Chloride, bicarbonate, sodium, potassium, phosphate)

• Proteins (Mucin, lysozyme, albumin, globulin)

• Amylase (Breaks down starch + sugar) + Lingual lipase

Functions of saliva:

1) Maintain ___ in mouth

2) ___ molecule involved in taste

3) Keeps mouth and teeth ___

4) Slightly ___, which protects against reflux and acid in foods

1) Moisture

2) Dissolves

3) Clean

4) Alkaline

Salivary Gland Cells:

1) Serous acinar cells ___ ___ components (amylase)

2) Mucous acinar cells secrete ____ ___

1) Secrete protein

2) Watery mucous

Xerostomia (Disease of the mouth)

Causes:

1) Salivary gland ____ ____ (____ syndrome)

2) ____: side effects of drugs, head/neck radiation for malignancies

Consequences:

3) ___ in oral pH with tooth decay and esophageal erosions

2) Difficulty in ____ and ____ food

3) ____ infections

1) Salivary gland autoimmune disease (Sjogren’s syndrome)

2) Latrogenic

3) Decrease in oral pH

2) Lubricating + swallowing

3) Opportunistic

Posterior 1/3 of Tongue (BEHIND)

1) Innervated by the ____ nerve (__) involved in ___. Note that this nerve also innervates the ___ gland (saliva)

Anterior 2/3 of Tongue (FRONT)

2) Innervated by ___ nerve (__) involved in ____

1) Glossopharyngeal nerve (IX); involved in taste; also innervates parotid gland (saliva)

2) Facial nerve (VII); Involved in taste

Taste Bud Types:

1) Anterior taste buds are found in ____ papillae

2) Posterior taste buds are found in ____ and ____ papillae

Taste Receptors:

3) GPCRs are the taste receptors for which taste types (3)

4) Ion channels are the taste receptors for which taste types (2)

5) ___-___ cells per taste bud activated by one taste and only ___ type of receptor per taste cell

1) Fungiform (front)

2) Foliate and circumvallate (back)

3) Sweet, bitter, umami

4) Sour, salty

5) 50-100 cells ; Only one receptor type per cell

Mechanism of Swallowing

The ___ connects the mouth and nose to the ____ and permits coordinated swallowing by preventing food from entering ___ passages or the ___

Pharynx; Esophagus, Nasal passages or the Trachea

Breakdown of esophagus:

1) Upper esophagus is comprised of ____ ____

2) Middle esophagus is comprised of what

3) Lower esophagus is comprised of ___ ____

1) Skeletal muscle

2) Skeletal muscle AND smooth muscle

3) Smooth muscle

Esophagus Muscle Anatomy

1) Skeletal muscle is innervated via ___ ____(s) in the CNS and permits ____ control over the initiation of the ___ reflux

2) Smooth muscle is innervated by the ___ nerve

3) Function of the esophagus is to transfer food bolus from the ___ to the ____

1) Skeletal muscle is innervated via motor neurons in the CNS and permits conscious control over the initiation of the swallowing reflux

2) Smooth muscle is innervated by the vagus nerve

3) Pharynx —> Stomach

Esophageal Sphincter:

1) What does the upper do

2) What does the lower do

3) ** Movement of food down the esophagus depends on ___ ___ aided by ____

4) Dysphagia: Difficulty swallowing can lead to change in medication dosage form, but this can result in what two things

1) Upper = allows passage of food to the stomach

2) Lower = allows passage of foot to stomach AND KEEPS IT THERE (prevents reflux)

3) Peristaltic contractions aided by gravity

4) Altered PK (absorption, distrubition) or drug deactivation (for pH sensitivte drugs)