Anatomy & Physiology-Saladin-Ch 25: Digestive System (Lecture Notes)

Front 1

?????Absorption

Back 1

(nutrients from outside to inside)

Slide #4

Front 2

The GI tract is made up of what organs?

Back 2

gastrointestinal (GI) tract is the stomach and intestines

Slide #6

Front 3

Is defecated food residue considered to have gone into the body tissues?

Back 3

In a strict sense, NO

MOST material that has entered the digestive tract has NOT actully entered the body tissues.

REASONING: it is considered to be external to the body until it is ABSORBED by the epithelial cells of the alimentary canal

Slide #7

Front 4

What tissue layers form the wall of the GI tract? (From inner to outer)

Back 4

inner to outer surface:

DIGESTIVE TRACT WALL:
(1) MUCOSA
epithelium
lamina propria
muscularis mucosae

(2) SUBMUCOSA

(3) MUSCULARIS EXTERNA
inner circular layer
outer longitudinal layer

(4) SEROSA
areolar tissue
mesothelium

Slide #8

Front 5

What is the Enteric Nervous System? Describe its function.

Back 5

Enteric Nervous System

– a nervous network in the esophagus, stomach, and intestines

FUNCTION: regulates digestive tract motility, secretion, and blood flow


Slide #12

Front 6

What are the mesenteries?

Back 6

mesenteries

– connective tissue sheets that loosely suspend the stomach and intestines from the abdominal wall

Slide #13

Front 7

What is the greater omentum?

Back 7

?????

Slide #15

Front 8

???

Back 8

the mouth is known as the oral, or buccal cavity


Slide #20

Front 9

???

Back 9

2 incisors – chisel-like cutting teeth used to bite off a piece of food


Slide #26

Front 10

???

Back 10

1 canine – pointed and act to puncture and shred food


Slide #26

Front 11

???

Back 11

2 premolars – broad surface for crushing and grinding


Slide #26

Front 12

???

Back 12

3 molars – even broader surface for crushing and grinding


Slide #26

Front 13

???

Back 13

gomphosis joint formed between tooth and bone (not two bones)


Slide #27

Front 14

???

Back 14

dentin – hard yellowish tissue that makes up most of the tooth


Slide #28

Front 15

???

Back 15

enamel – covers crown and neck


Slide #28

Front 16

???

Back 16

pulp cavity in the crown
nerves and blood vessels


Slide #29

Front 17

???

Back 17

Tooth and Gum Disease



Slide #31

Front 18

???

Back 18

salivary amylase – enzyme that begins starch digestion in the mouth


Slide #33

Front 19

???

Back 19

lingual lipase – enzyme that is activated by stomach acid and digests fat after the food is swallowed


Slide #33

Front 20

???

Back 20

mucus – binds and lubricates the mass of food and aids in swallowing


Slide #33

Front 21

???

Back 21

lysozyme – enzyme that kills bacteria


Slide #33

Front 22

???

Back 22

But they don’t have protease


Slide #33

Front 23

???

Back 23

lingual glands – in the tongue – produce lingual lipase (intrinsic)


Slide #34

Front 24

???

Back 24

submandibular gland – located halfway along the body of the mandible (extrinsic)


Slide #34

Front 25

???

Back 25

lower esophageal sphincter – food pauses at this point because of this constriction


Slide #39

Front 26

???

Back 26

heartburn – burning sensation produced by acid reflux into the esophagus


Slide #39

Front 27

???

Back 27

swallowing center – pair of nuclei in medulla oblongata that coordinates swallowing


Slide #41

Front 28

???

Back 28

buccal phase – under voluntary control (from CNS)


Slide #41

Front 29

???

Back 29

pharyngoesophageal phase – is involuntary (autonomic reflexes)


Slide #42

Front 30

???

Back 30

Gastric rugae


Slide #47

Front 31

???

Back 31

parietal cells – found mostly in the upper half of the gland
secrete hydrochloric acid (HCl), intrinsic factor, and a hunger hormone called ghrelin


Slide #53

Front 32

???

Back 32

chief cells – most numerous
secrete gastric lipase and pepsinogen


Slide #53

Front 33

???

Back 33

zymogens – digestive enzymes secreted as inactive proteins (they are only secreted into the lumen)


Slide #57

Front 34

???

Back 34

Gastric Motility


Slide #62

Front 35

???

Back 35

gastric phase


Slide #72

Front 36

???

Back 36

enterogastric reflex – duodenum sends inhibitory signals to the stomach by way of the enteric nervous system and signals to the medulla oblongata - triggered by acid and semi-digested fats in the duodenum


Slide #74

Front 37

???

Back 37

inhibitory signals


Slide #74

Front 38

???

Back 38

***Hepatic triad:

(1) Branch of
hepatic
portal vein
(2) Branch of
proper hepatic
artery
(3) Bile ductule


Slide #80

Front 39

???

Back 39

***hepatic macrophages (Kupffer cells) – phagocytic cells in the sinusoids that remove bacteria and debris from the blood


Slide #81

Front 40

???

Back 40

between meals, hepatocytes(of liver) breaks down stored glycogen and releases glucose into the blood


Slide #82

Front 41

???

Back 41

***hepatic triad of two vessels and a bile ductule, visible in the triangular areas where three or more lobules meet

Slide #83

Front 42

???

Back 42

***hepatic macrophages (Kupffer cells) – phagocytic cells in the sinusoids that remove bacteria and debris from the blood


Slide #81

Front 43

???

Back 43

between meals, hepatocytes(of liver) breaks down stored glycogen and releases glucose into the blood


Slide #82

Front 44

???

Back 44

***hepatic triad of two vessels and a bile ductule, visible in the triangular areas where three or more lobules meet

Slide #83

Front 45

???

Back 45

***Microscopic Anatomy of LiverKnow the order!!!


Slide #85

Front 46

???

Back 46

bile acids (bile salts) – steroids synthesized from cholesterol
bile acids and lecithin, a phospholipid, aid in fat digestion and absorption


Slide #88

Front 47

???

Back 47

Pancreatic Zymogens


Slide #93