Human Body Lecture Exam 3 (Digestive System)

Front 1

Gastrointestinal Tract (GI Tract)

Back 1

also called alimentary canal
a continuous muscular tube that runs through the body, open at both ends

Front 2

2 Main functions of the GI Tract

Back 2

1. Digest Food
2. Absorbs Digested Fragments

Front 3

3 Accessory Digestive Organs

Back 3

1. Teeth and Tongue
2. Gallbladder
3. Accessory Digestive Glands

Front 4

Is the Gall Bladder a gland?

Back 4

NO

Front 5

3 Accessory Digestive Glands

Back 5

1. Salivary Gland
2. Pancreas
3. Liver

Front 6

Ingestion

Back 6

taking food into the tract

Front 7

Propulsion

Back 7

Moving food through the tract:
swallowing
peristalsis

Front 8

Peristalsis

Back 8

involuntary, alternate waves of contraction/relaxation that squeeze food through tract

Front 9

Mechanical Digestion

Back 9

physically changes food in preparation for chemical digestion

Front 10

4 Types of Mechanical Digestion:

Back 10

1. Chewing
2. Mixing food with saliva
3. Churning food in stomach
4. Segmentation

Front 11

Segmentation

Back 11

local constrictions of intestine
food is moved forward and backwards
Mixing NOT propulsion

Front 12

Chemical Digestion

Back 12

Carbohydrates, lipids, and proteins are broken down to chemical building blocks that can be absorbed.

Front 13

exocrine gland

Back 13

secrete through ducts to the outside of the body (lumen of GI tract)

Front 14

Where are enzymes that undergo chemical digestion produced?

Back 14

exocrine glands

Front 15

Absorption

Back 15

Movement of molecules from the lumen of GI tract into either blood or lymph

Front 16

Defecation

Back 16

elimination of indigestible substances from the body

Front 17

3 Ways to Control Digestive Activity

Back 17

1. Innervation of glands
2. Innervation of smooth muscle
3. Via Hormones

Front 18

Where are the hormone secreting cells located?

Back 18

stomach and small intestine

Front 19

Intrinsic Control (Short Reflexes)

Back 19

control is plexus of nerves within walls of GI Tract

Front 20

enteric nervous system

Back 20

the plexus of nerves within the wall of GI tract used in Intrinsic control

Front 21

Gut Brain

Back 21

another name for the enteric nervous system

Front 22

Extrinsic Controls (Long Reflexes)

Back 22

controls exerted from autonomic nervous system in CNS
(parasympathetic and sympathetic)

Front 23

Parasympathetic

Back 23

(Breed and Feed) enhances secretory activity and motility

Front 24

Sympathetic

Back 24

inhibits digestive activity

Front 25

SF - Lips

Back 25

S- core of skeletal muscle (orbicularis oris) covered in skin
F- keep food between our teeth when we chew

Front 26

Oral Cavity

Back 26

only part of GI tract involved in ingestion

Front 27

SF - Cheeks

Back 27

S - core of skeletal muscle (buccinator) covered externally by skin
F - help keep food between teeth when we chew

Front 28

Hard Palate

Back 28

-bony roof of oral cavity formed by maxillae and palatine bones
-rough, rigid surface used for mechanical digestion

Front 29

SF - Soft Palate

Back 29

S - mobile fold formed mostly of skeletal muscle
F - rises reflexively to close off the nasopharynx when we swallow

Front 30

SF - Tongue

Back 30

S - composed of interlacing bundles of skeletal muscle fibers (intrinsic and extrinsic muscles)
F - grips and repositions food between teeth and mixes food with saliva

Front 31

What forms the boundaries of the oral cavity?

Back 31

lips, cheeks, the palate, tongue

Front 32

deglutition

Back 32

swallowing includes the buccal phase (voluntary) and the pharyngeal - esophageal phase (involuntary)

Front 33

Mumps

Back 33

a viral disease that causes inflammation of the parotid glands

Front 34

Extrinsic Salivary Glands

Back 34

release saliva into oral cavity by ducts
parotid glands
submandibular
sublingual

Front 35

Submandibular Glands

Back 35

2 glands under the base of the tongue

Front 36

Sublingual Glands

Back 36

2 glands under tongue, anterior to submandibular (Gleeking)

Front 37

Intrinsic Salivary Glands

Back 37

buccal glands; are scattered throughout oral cavity and secrete small amount continuously

Front 38

Average Output of Saliva a day

Back 38

1000 - 1500 mL

Front 39

ferritin

Back 39

a protein that ionic iron binds to in the mucosal cells

Front 40

transferrin

Back 40

a plasma protein that iron binds to in the blood, it transports it in circulation

Front 41

saliva

Back 41

contains water (97% - 99.5%) and ions, digestive enzyme (salivary amylase) and mucus

Front 42

saliva and it's function in protection from microorganisms

Back 42

contains:
antibodies
lysozyme
a cyanide compound
defensins

Front 43

defensins

Back 43

part of saliva, chemicals that attract WBC's

Front 44

2 incisors function

Back 44

clipping and cutting

Front 45

1 canine

Back 45

tearing

Front 46

2 pre-molars

Back 46

bicuspids

Front 47

3 molars

Back 47

4 - 5 cusps

Front 48

deciduous teeth

Back 48

baby or milk teeth
appear at 6 months with lower incisors

Front 49

When do you get all 20 of your deciduous teeth?

Back 49

after 24 months

Front 50

When are your deciduous teeth fully replaced by?

Back 50

by 13 years

Front 51

When do your permanent teeth appear?

Back 51

around 6 years (32 total)

Front 52

When do your 3rd molars (wisdom teeth) appear?

Back 52

between 17 and 25 years

Front 53

Dentin

Back 53

bone-like MATERIAL; bulk of tooth
contains collagen
laid down rapidly

Front 54

odontoblasts

Back 54

produce dentin throughout your lifetime

Front 55

Pulp

Back 55

c.t., blood vessels and nerves in a central pulp cavity (MATERIAL)
supplies nutrients to tooth and provides tooth sensation

Front 56

heterodont

Back 56

means "different teeth"
means structurally - we have no dominant teeth
functionally - we are omnivores

Front 57

crown

Back 57

the exposed part above gum (gingiva) line (REGION)

Front 58

enamel

Back 58

covers the dentin
hardest substance in the body
densely packed hydroxyapatites
NO collagen

Front 59

Neck

Back 59

constriction between crown and root

Front 60

Root

Back 60

part of tooth embedded in jawbone
teeth have 1 -3

Front 61

Cementum

Back 61

calcified c.t. that surrounds the dentin in the ROOT

Front 62

periodontal ligament

Back 62

anchors tooth in jawbone in a fibrous joint (gomphosis)

Front 63

Root Canal

Back 63

part of pulp cavity in ROOT; open at base for vessels and nerves to pass through

Front 64

caries (cavities)

Back 64

demineralization of enamel and dentin by a certain type of anaerobic bacteria

Front 65

plaque

Back 65

film of sugars, bacteria, mouth debris that sticks to teeth

Front 66

What is the pH of the mouth?

Back 66

usually slightly acidic (6.75 to 7)

Front 67

What is saliva pH based on?

Back 67

varies based on HCO- (a buffer) which increases with flow rate

Front 68

Periodontal Disease

Back 68

95% of people over 35
accounts for around 90% of tooth loss

Front 69

calculus ("stone")

Back 69

plaque accumulates and calcifies causing separation between gums and teeth

Front 70

tartar

Back 70

the same as calculus

Front 71

2 ways that periodontal disease increases the risk of heart disease:

Back 71

1. Chronic Inflammation promotes atherosclerosis
2. Bacteria enters blood from infected gums and can cause clot formation that clogs the coronary arteries

Front 72

GERD

Back 72

Gastroesophageal Reflux Disease
can cause esophageal cancer

Front 73

stomach

Back 73

muscular sac in superior, left part of abdominal cavity

Front 74

small intestine

Back 74

the major digestive organ, digestion is completed (both mechanical and chemical) and almost ALL absorption.

Front 75

Duodenum

Back 75

10 inches
receives bile from gallbladder / liver duct
receives pancreatic juice from a duct

Front 76

Dimensions of small intestine

Back 76

1 inch in diameter
21 feet in length!!

Front 77

Plicae Circulares

Back 77

permanent folds in lining of small int.
slows down movement of chyme (creamy past of food)
spirals

Front 78

Villi

Back 78

finger-like projections off of plicae circulares
mainly made of enterocytes

Front 79

enterocytes

Back 79

absorptive columnar cells

Front 80

core of villus

Back 80

where absorption takes place
dense capillary bed
lacteal
slip of smooth muscle

Front 81

lacteal

Back 81

wide lymph capillary

Front 82

Microvilli

Back 82

tiny projections of enterocyte plasma membrane

Front 83

Bile

Back 83

stored in the gallbladder
is an emulsifying agent
causes large fat droplets to be broken into tiny droplets increasing SA for action of lipase

Front 84

Is bile an enzyme?

Back 84

NO

Front 85

Gallstones

Back 85

80 - 90% are a bile salt cholesterol derivative

Front 86

Bilirubin

Back 86

chief pigment in bile
yellow green in color
a waste product of heme after iron is recycled

Front 87

jaundice

Back 87

over-abundance of bilirubin in blood

Front 88

Acini

Back 88

clusters of secretory cells that produce all the pancreatic enzymes

Front 89

pancreatic juice

Back 89

digestive enzymes
watery, alkaline secretion (pH 8)

Front 90

Large Intestine Dimensions

Back 90

2.5 inches in diameter
5 feet in length

Front 91

haustral contractions

Back 91

happen every 30 minutes
reflect local control
mix fecal material to facilitate water reabsorption
move contents into next haustra

Front 92

Mass Movements (mass peristalsis)

Back 92

occurs 3 - 4 time daily
typically during or just after eating

Front 93

What Vitamins are produced in the large intestine

Back 93

synthesize some B vitamins and most of the VItamin K that the liver needs to produce clotting proteins

Front 94

Are there gut enzymes in the large intestine?

Back 94

NO