Digestive System

Question 1

What consists of the digestive system?

Answer 1

oral cavity, pharynx, esophagus, small intestine, stomach, large intestine, anus

Question 2

What does the digestive system accomplish? 4 things.

Answer 2

1. Ingestion 2. Digestion 3. Absorption 4. Elimination or Defacation

Question 3

Ingestion

Answer 3

process of taking in food or liquid through the mouth which initiates the digestive process

Question 4

Mechanical digestion

Answer 4

chewing

Question 5

Chemical digestion

Answer 5

break down by enzymes

Question 6

How is the tongue specialized for gustation?

Answer 6

Covered in lingual papillae

Question 7

What are the 4 types of papillae?

Answer 7

Vallate
Foliate
Fungiform
Filiform

Question 8

Which papillae contain taste buds?

Answer 8

Vallate, Foliate, Fungiform

Question 9

What do each taste bud house?

Answer 9

several epithelial chemoreceptor cells
(gustary receptor cells, supporting cells, stem cells)

Question 10

How dotaste receptor cells communicate?

Answer 10

through taste pores, small openings o the oral cavity, with their microvilli

Question 11

Tastants

Answer 11

dissolved chemicals

Question 12

How are gustatory receptor stimulated?

Answer 12

By tastants

Question 13

Taste transduction

Answer 13

taste receptor cells convert tastants into neural signals

Question 14

What does taste transduction lead to?

Answer 14

Release of neurotransmitters which bind to primary afferent neurons that transmit information to the CNS

Question 15

What happens to signals during taste?

Answer 15

enter the CNS at the hindbrain where the yare filtered by the thalamus and relayed to the cerebrum

Question 16

What can activation of taste afferent neurons trigger?

Answer 16

salivation reflex, gag reflex, gastric reflexes

Question 17

Swallowing

Answer 17

process of which food moves from the mouth into the stomach

Question 18

3 phases of swallowing

Answer 18

Buccal
Pharyngeal
Esophageal

Question 19

What is the only voluntary stage of swallowing?

Answer 19

Buccal

Question 20

Buccal phase of swallowing

Answer 20

Follows chewing,

Question 21

What is the involuntary phase of swallowing?

Answer 21

Pharyngeal

Question 22

What happens during the Buccal phase of swallowing?

Answer 22

Tongue moves upward and backward against the soft palate, which propels the bolus back into the oral cavity into the oropharynx

Question 23

What happens during the Pharyngeal phase of swallowing?

Answer 23

Nasopharynx is blocked by the uvula, pharyngeal muscles lift larynx, epiglottis folds over

Pharyngeal muscles constrict forcing the the bolus down pased the closed larynx into the esophagus

Question 24

When does Pharyngeal phase begin?

Answer 24

When tactile receptors on the palate and uvula are stimulated

Question 25

What is the esophagus?

Answer 25

Muscular hollow tube connecting the pharynx to the stomach

Question 26

How do the muscles of the esophagus facilitate movement of the bolus?

Answer 26

Through peristalsis, sequential, alternating waves of contraction and relaxation

Question 27

What happens in esophageal phase of swallowing?

Answer 27

The bolus moves from the pharynx through the esophagus into the stomach

Question 28

How does peristalsis work?

Answer 28

Circular muscles narrow the lumen behind the bolus Longitudinal layer contractions shorten the tube ahead of the bolus

Question 29

Salivary glands

Answer 29

glands that secrete saliva int othe oral cavity through ducts

Question 30

Sublinguinal glands produce

Answer 30

mucous that acts as a buffer and lubricant

Question 31

Submandibular glands produce

Answer 31

mixture of buffers, mucin and salivary amylase

Question 32

Parotid glands produce

Answer 32

large amounts of salivary amylase

Question 33

What does saliva do?

Answer 33

aids in tastem digestion, lubrication and protection

Question 34

What composes saliva?

Answer 34

Digestive enzyme (salivary amylase and lipase) antibacterial enzymes, lysozymes antibodies, IgA electrolytes that buffer the osmolarity and pH of oral cavity glycoproteins, mucins lubricate food and tissues

Question 35

Salivatory reflex

Answer 35

Activation of chemoreceptors (taste cells) and mechanoreceptors in the oral cavity trigger salivation via long reflexes which are integrated in the medulla

Question 36

What innervates salivary glands?

Answer 36

Both Parasympathetic and Sympathetic

Question 37

What does Parasympathetic activity do for saliva secretion?

Answer 37

enhances the rate of secretion of saliva

Question 38

What does Sympathetic activity do for saliva secretion?

Answer 38

stimulates secretion but reduces the volume of saliva produced