Lecture 16: Digestive system two

Question 1

what is the mechanical digestion for food called?

Answer 1

Mastication

Question 2

whats the function of saliva?

Answer 2

lubricate food
amylase”digests starch and glycogen
dissolves molecules for taste

Question 3

how is food propelled to the pharynx?

Answer 3

propelled by the tongue

Question 4

how is the enamel of teeth made?

Answer 4

by ameloblasts.

Question 5

how is dentin for teeth made?

Answer 5

odontoblasts.

Question 6

what does the Pulp cavity contain?

Answer 6

blood vessels and nerve endings

Question 7

is the tongue a skeletal muscle?

Answer 7

yes

Question 8

whats the scientific term for taste buds?

Answer 8

papillae

Question 9

what glands does the tongue have?

Answer 9

lingual glands

Question 10

what another term for pharynx ?

Answer 10

throat

Question 11

what is the pharynx used for?

Answer 11

air fluid and food

Question 12

how’s does food enter the pharynx ?

Answer 12

via the esophagus

Question 13

what is the esophagus?

Answer 13

Muscular tube from pharynx to stomach

Question 14

How many sphincters does the oesophagus have?

Answer 14

two
Upper esophageal sphincter
Lower esophageal sphincter

Question 15

where is the Upper esophageal sphincter

located?

Answer 15

Between pharynx and esophagus

Question 16

where is the lower esophageal sphincter

located?

Answer 16

Between esophagus and stomach

Question 17

what does the lower esophageal sphincter do?

Answer 17

Prevents the acidic content of the stomach from entering the esophagus

Question 18

what are the three stages of swallowing?

Answer 18

1. Oral preparatory phase
2. Pharyngeal phase
3. Oesophageal phase

Question 19

what is the Oral preparatory phase?

Answer 19

Chewing, saliva, food formed into bolus by tongue, soft palate closes to prevent nasal aspiration (voluntary control)

Question 20

what is the Pharyngeal phase?

Answer 20

bolus moved by peristalsis (involuntary), epiglottis blocks trachea

Question 21

what is the Oesophageal phase?

Answer 21

peristalsis waves move bolus, lower esophageal sphincter relaxes to allow bolus into stomach

Question 22

what are the three regions of the stomach?

Answer 22

fundus, body, antrum

Question 23

what is the funds of the stomach?

Answer 23

Thin wall that easily expands

Question 24

what is the body of the stomach?

Answer 24

Gastric mucosa folds in Rugae

Question 25

what is the antrum of the stomach?

Answer 25

Thickest muscle, produces contractions responsible for gastric mixing and emptying

Question 26

what does the Pyloric sphincter do?

Answer 26

regulates the passage of chyme to duodenum

Question 27

what are the functions of the stomach?

Answer 27

``` store food mechanical digestion chemical digestion secretion of muscus Passage of chyme to small intestine Secretion of intrinsic factor ```

Question 28

How much food can the stomach hold?

Answer 28

4L

Question 29

what secretes gastric juice?

Answer 29

stomach

Question 30

what are the components of gastric juice?

Answer 30

- Mucus - HCl - Pepsinogen - Intrinsic factor - Gastric lipase

Question 31

Ho long and wide is the small intestine?

Answer 31

4m long and 2.5cm diameter

Question 32

what are the sub divisions of the SI?

Answer 32

duodenum, jejunum, ileum

Question 33

where is the duodenum located?

Answer 33

it is attached to the stomach, and curves around the head of the pancreas

Question 34

where is the jejunum located?

Answer 34

Attached anteriorly to the duodenum

Question 35

where is the ileum located?

Answer 35

Extends from jejunum to large intestine | Meets the large intestine at the ileocecal valve

Question 36

whats the functions of the small intestines?

Answer 36

motility secretion of alkaline msucus major site of digestion major site of absorption

Question 37

what is motility?

Answer 37

Segmentation and Peristalsis

Question 38

what increases the SA of the wall of the small intestine?

Answer 38

Circular folds, villi, microvilli

Question 39

what are brush border enzymes?

Answer 39

Disaccharidases (maltase, sucrase, lactase) Peptidases (Enteropeptidase- activates trypsinogen) Phosphatases

Question 40

what are the sections of the large intestines?

Answer 40

``` Cecum Appendix Colon rectum anal canal ```

Question 41

whats the size of the large intestine?

Answer 41

1.3m long, 6.3cm diameter

Question 42

what does the colon empty into?

Answer 42

rectum

Question 43

where is faces excreted from?

Answer 43

anus

Question 44

what type of muscle does the internal anal sphincter have?

Answer 44

smooth msucle

Question 45

what type of muscle does the external anal sphincter have?

Answer 45

skeletal muscle

Question 46

whats the function of the large intestine?

Answer 46

``` Water absorption Electrolyte absorption waves and mass movements Mucus secretion Synthesis of B12 and K Reservoir of undigested material prior to elimination ```

Question 47

what does intestinal bacteria do in the large intestine?

Answer 47

perform fermentation reactions that produce short chain fatty acids and flatus.