Ch.23: Digestive System Part 1

Question 1

The Two main groups of the digestive system

Answer 1

• alimentary canal (mouth, pharynx, esphagus, stomach, small intestine, and large intestine)
• accessory digestive organs (teeth, tongue, gallbladder, salivary glands, liver, and pancreas)

Question 2

______________, also called gastrointestinal tract or gut, the continuous muscular tube that winds through the body from the mouth to the anus. It digest food and absorbs

Answer 2

Alimentary canal

Question 3

__________ help produce a variety of secretions that help breakdown foodstuffs

Answer 3

accessory digestive organs

Question 4

The proccessing of food by the digestive system involves six essential activities:

Answer 4

Ingestion
Propulsion (swallowing/peristalsis)
Mechanical breakdown (segmentation)
Digestion
Absorption (blood/lymph)
Defecation

Question 5

Layers of the peritoneum on the abdominopelvic cavity

Answer 5

• visceral peritoneum(external surface of digestive organs)
• parietal peritoneum(lines the body wall)
• peritoneum cavity (lubrication)
• Mesentery (double layer of peritoneum, provides routes for blood vessels, lymphatics and nerves, holds organs in place and store fat)

Question 6

Layers of the GI Tract

Answer 6

• Mucosa
• SubMucosa
• Muscularis externa
• Serosa (Visceral Peritoneum)

Question 7

Three Major Functions of the Mucosa

Answer 7

• secretes mucus, digestive enzymes and hormones
• absorbs the end products of digestion
• protect against infectious disease

Question 8

Three sublayers of Mucosa are:

Answer 8

• Lining epithelium (simple columnar epithelium, goblet cells)
• Lamina propria (nourish and absorb MALT)
• Muscularis mucosae (smooth muscle, movements)

Question 9

Function of Submucusa and what it contains:

Answer 9

• areolar connective tissue, rich supply of blood and lymphatic vessels
• enable the stomach to regain its normal shape after a large meal

Question 10

Function of The Muscularis Externa and what it contains:

Answer 10

• responsible for segmentation and persistalsis

- circular muscles and longitudinal muscles

Question 11

Function of Serosa:

Answer 11

• also called visceral peritoneum

- a single layer of squamous epithelium

Question 12

Intrinsic control:_______ _______ form ganglia and plexuses that communicate with each other to regulate digestive activity.

Answer 12

Enteric Neurons

Question 13

Extrinsic control:

Answer 13

• regulated by the autonomic nervous system
• linked to the CNS Sym& paraSym
• sym. decreases Gi tract motlity, secretionand hunger
• Parasym. vagus nerve, Increase

Question 14

_______, occupies the floor of the mouth, is composed of interlacing bundles of skeletal muscle fibers. During chewing it grips the food and constantly repositions it between the teeth. Mixes the food with saliva forming it in to a bolus.

Answer 14

Tongue

Question 15

_______ ______ roughen the tongue surface, lick semisolids food, such as ice creams, provide friction for manipulating foods

Answer 15

filliform papillae

Question 16

Function of the Saliva

Answer 16

• cleanse the mouth
• dissolves food chemicals so they can be tasted
• moistens food and helps compact it into a bolus
• contains enzymes that begin the chemical breakdown of starchy food

Question 17

Three types of salivary glands:

Answer 17

• parotid gland
• submandibular gland
• sublingual gland

Question 18

Two types of secretory cells:

Answer 18

• Serous cells ( produce watery secretion containing enzymes, ions, and solution)
• Mucous cells (produce mucus)

Question 19

Composition of Saliva:

Answer 19

• 99.5% water and .5% Solutes
• slightly acidid pH (6.5 to 7.00)
• salivary amylase (polysacchrides) and lingual lipase (triglycerides)
• lysozyme (prevent tooth decay)
• IgA and defensins

Question 20

________ ________, also called milky, or baby teeth. 20 milk teeth have emerged

Answer 20

Deciduous teeth

Question 21

Permanent teeth have _____ in a full set

Answer 21

32`

Question 22

The __________ prevents the food from entering into the wrong tube

Answer 22

Epiglottis

Question 23

Characteristics of the Esophagus:

Answer 23

• muscular tube, 10 inches
• pierces the diaphragm at the esophageal hatius
• no chemical digestion
• fibrous adeventitia

Question 24

_________, first symptom of gastroesophageal reflux disease, is the burning radiating substernal pain that occurs when stomach acid regurgitates into the esphagus

Answer 24

heartburn

Question 25

Digestive Process: Mouth to Esophagus:

Answer 25

Mouth

• ingest,
• begins mechanical breakdown by chewing,
• initiates propulsion by swallowing,
• starts chemical breakdown (polysacchrides)

Question 26

As food enters the mouth, its mechanical breakdown begins with __________, or chewing. It’s partly voluntary and partly reflexive.

Answer 26

Mastication

Question 27

_____________, or swallowing is a complicated process that involves coordinated activity of over 22 seperate muscle groups. Two major phases: the buccal and the pharyngeal-esophageal.

Answer 27

Deglutination