GI 2 and 3

Question 1

Digestion

Answer 1

Chemical and mechanical breakdown of food into absorbable units

Question 2

Secretion

Answer 2

Movement of material from cells of the lumen or ECF

Question 3

Absorbtion

Answer 3

Movement of material from GI lumen to ECF

Question 4

mobility

Answer 4

Movement of material through the GI tract as a result of muscle contraction

Question 5

Challenges of the digestive system

Answer 5

Avoiding autodigestion
Defense
Maintaining mass balance

Question 6

Avoiding Autodigestion

Answer 6

Breaking food down into small enough molecules to be absorbed without digesting the cell of the GI tract

Question 7

Defense

Answer 7

Absorbing water and nutrients while preventing bacteria, viruses and other pathogens from entering the body.

Question 8

mechanisms of defense

Answer 8

Mucus, digestive enzymes, acid and the largest collection of lymphoid tissue

Question 9

Fluid secretions

Answer 9

Water, Digestive Enzymes and Mucus

Question 10

Water

Answer 10

Ions are transported from ECF into the Lumen
Creates osmotic gradient for water movement

Question 11

Digestive Enzymes

Answer 11

• Exocrine glands (Salivary and pancreas)
• Epithelial cells in stomach and small intestine

Question 12

Zymogen

Answer 12

Inactive enzymes

Question 13

Mucus

Answer 13

Viscous glycoprotein (mucins) secretions that protect GI cells and lubricate the contents

Question 14

Most fluid secretion fascilitates

Answer 14

Digestion

Question 15

Two purposes of motility

Answer 15

1. Moves food from mouth to anus
2. Mechanically mixing food breaks it into uniformly small particles

Question 16

Muscles involved in motility

Answer 16

Skeletal and Smooth Muscle

Question 17

How are smooth muscles of motility modifies

Answer 17

Chemical and mechanical input from nerves
Hormones and paracrine signals

Question 18

Phasic smooth muscle

Answer 18

Cycle of contraction and relaxation
In esophagus, stomach and large intestile

Question 19

Slow wave

Answer 19

Modified by chemical input from neurons, hormones and paracrine signals

Question 20

Where do slow waves likely orginate from

Answer 20

Interstitial cells of cajal (icc)

Question 21

ICC

Answer 21

Modified smooth muscle cells serving as the pacemaker for slow wave activity

Question 22

Migrating Motor Complex

Answer 22

Starts in stomach and passes from section to section terminating at the ilum (Through the small intestine)
Inbetween meals.
Sweeps food remnants and bacteria out of the upper GI tract and into the large intestine

Question 23

Peristaltic Contractions

Answer 23

During or following a meal
Circular layer of smooth muscle: Contracts responsible for forward movement

Question 24

Segmental Contractions

Answer 24

Are responsible for mixing
Circular and longitudinal contractions

Question 25

Primarily Regulated functions of GI system

Answer 25

Motility and secretion

Question 26

Neural regulation

Answer 26

Submucosal and myenteric plexuses from the ENS Neurons synapse with each other. Smooth muscles, glands and epithelial cells Short reflexes integrated entirely within the ENS Long reflexes integrated within the CNS

Question 27

GI peptides

Answer 27

Hormones, neuropeptides and cytokines

Question 28

Similarities of ENS and CNS

Answer 28

intrinsic neurons: Entirely within the GI tract Neurotransmitters and neuromodulators Has glial support cells: Similar to astrocytes Diffusion barrier Integrating center

Question 29

Short reflexes

Answer 29

Original in the ENS, and carried out entirely within the wall of the gut

Question 30

Mycentric plexus control

Answer 30

Motility

Question 31

Submucosal plexus control

Answer 31

Secretion from GI secretory cells

Question 32

Long reflexes

Answer 32

Integrated in the CNS

Question 33

When a long reflex begins in the brain

Answer 33

Cephalic reflex

Question 34

PNS

Answer 34

Enhances GI functioning

Question 35

Which region of the GI tract has a large amount of bacteria

Answer 35

Large Intestine

Question 36

Movement from lumen of the GI tract into the ECF

Answer 36

Absorption

Question 37

Two families of HOEMONES

Answer 37

Gastrin Family secretion Family

Question 38

3 Phases within the digestive system

Answer 38

Cephalic/oral phase Gastric Phase intestinal phase

Question 39

How is cephalic phase increased

Answer 39

From parasympathethietic output from medulla

Question 39

Cephalic phase

Answer 39

Digestive processes can actually start before food enters the mouth and are reinforced once food enters the GI tract In a feedforward fashion

Question 40

once food enters the mouth

Answer 40

Mastification (Increased Parasympathethetic output)

Question 41

3 main salivary glands

Answer 41

Parotid Gland Sublingual Gland Submandibular Gland

Question 42

4 functions of the salivary glands

Answer 42

Softens and moisten food Digestion of Carbohydrates (Amylase) Dissolve foods (Taste) Defence (Lysozome)

Question 43

Where are secretory cells of saliva found

Answer 43

Acini

Question 44

All glands are not

Answer 44

Identical

Question 45

Parotid

Answer 45

Watery solution with amylase (Just serous cells)

Question 46

Submandibular

Answer 46

Similar to parotid plus some mucus. Many serous, some mucus cells

Question 47

Sublingual

Answer 47

Mainly mucus cells

Question 48

Degutition

Answer 48

Reflex that pushes the bolus of good into the esophagus

Question 49

What stares swallowing

Answer 49

Tongue pushing up

Question 50

swallowing centre

Answer 50

medulla