Physio Ii Midterm Gi- Part I

Front 1

The digestive system’s function is to supply nutrients from the environment to where?

Back 1

The circulatory system

Front 2

The digestive system is a long tube that, in function, resembles a what?

Back 2

Processing plant

Front 3

The function of this processing plant is to convert what into absorbable micromolecules?

Back 3

Macromolecules

Front 4

Name some of the macromolecules in the digestive process

Back 4

Proteins, fats, carbohydrates

Front 5

Name some of the micromolecules in the digestive process.

Back 5

Amino acids, fatty acids, monsaccharides

Front 6

By which two means does the digestive system convert macromolecules to micromolecules?

Back 6

Mechanical and chemical

Front 7

The digestive system uses 3 fundamental processes . One involves smooth muscle contraction to crush, mix and propel contents, this process is called….

Back 7

Motility or mechanical digestion

Front 8

Chemical digestion, the delivery of digestive enzymes, mucus, ions and fluids, can also be called…

Back 8

Secretions

Front 9

The transport of nutrients, water and ions across the epithelium is which process?

Back 9

Absorption

Front 10

Digestions requires tight controls involving what two types of messages?

Back 10

Hormonal and neuro

Front 11

The purpose of hormonal & neuron messages during the digestion process is to _______.

Back 11

Adjust GI activity to the quality/quantity of incoming food
Facilitate communication between the GI sections and the CNS

Front 12

What is the predominant function of the mouth in the digestive process?

Back 12

Mechanical breakdown of food

Front 13

What is added to food in the mouth that serves as a lubricant?

Back 13

Saliva

Front 14

Which organ is the conduit from the mouth to the stomach?

Back 14

Esophagus

Front 15

What functions occur in the stomach?

Back 15

Chemical digestion of proteins, liquefaction of food

Front 16

Which organ provides bile salts for the digestion of fats and stores fat?

Back 16

Liver

Front 17

What is the predominant function of the pancreas in the digestive process?

Back 17

Provision of major digestive enzymes

Front 18

What function does the large intestine have?

Back 18

Absorption of water, feces formation, bacterial fermentation (major species differences)

Front 19

In ruminants, what organ is responsible for the fermentation of nutrients and absorption of fermentation products?

Back 19

Forestomach

Front 20

What is the function of the small intestines?

Back 20

Provision of enzymes, chemical digestion and absorption of nutrients and water

Front 21

Large macromolecules need to be what before they can be digested?

Back 21

Hydrolyzed

Front 22

Peptides are broken down into what micromolecules?

Back 22

Amino acids

Front 23

Monoglycerides and fatty acids are the product of what type of molecules being hydrolyzed?

Back 23

Lipids

Front 24

What is the product of carbohydrate hydrolysis?

Back 24

Glucose

Front 25

The digestive tract is mostly a long, smooth muscle tube, geared towards coordinated motility. This coordination is referred to as…

Back 25

Syncytium, single-unit type

Front 26

The digestive tract is comprised of what 3 main layers?

Back 26

Longitudinal muscle, circular muscle, lamina muscularis mucosae

Front 27

Similar to the AV node of the heart, the GI muscle cells are what type of cells?

Back 27

Self-excititory

Front 28

What type of membrane potentials do the cells of the GI muscle exhibit?

Back 28

Undulating resting membrane potentials

Front 29

The undulating membrane potentials in the cells of the GI muscle are also known as

Back 29

Slow waves

Front 30

The undulating slow waves have a value of approximately..

Back 30

-50 to -60 mV

Front 31

The slow waves are conducted along a GI section because of what structure?

Back 31

Gap junctions

Front 32

What is the frequency of the the slow waves?

Back 32

3-12/ min…depending on gut section

Front 33

Slow waves are classified as what type of contraction?

Back 33

None! They are NOT contractions

Front 34

A slow wave has to reach what to elicit a muscle contraction?

Back 34

Critical threshold potential

Front 35

The value of the critical threshold is what?

Back 35

-40 to -35 mV

Front 36

What happens after the critical threshold is reached?

Back 36

Voltage-gated calcium channels open rapid influx of calcium causes spike potentials and elicits muscle contractions

Front 37

Where does the muscle contraction go?

Back 37

Along a section of the GI tract

Front 38

The amplitude of slow waves can be modulated by what 2 types of factors?

Back 38

Priming factors, hyperpolarizing factors

Front 39

What is the effect of priming factors?

Back 39

Depolarize smooth muscle membranes

Front 40

What does depolarizing smooth muscle membranes achieve?

Back 40

More slow waves reach threshold-GI motility increases

Front 41

Give 2 examples of priming factors

Back 41

Gut wall stretching, parasympathetic stimulation, some GI hormones

Front 42

What effect do hyperpolarizing factors have?

Back 42

GI motility decreases

Front 43

Name 2 hyperpolarizing factors.

Back 43

Sympathetic stimulation, some GI hormones

Front 44

Name the 2 basic patterns of GI motility

Back 44

Segmentation (mixing) and peristalsis (propulsion)

Front 45

Segmentation (mixing) is achieved by localized contraction of what type of muscle?

Back 45

Circular muscle

Front 46

Does this type of motility pattern (mixing) occur over a long or short distance?

Back 46

Short

Front 47

What effect does segmentation produce?

Back 47

Chopping/mixing effect on gut contents

Front 48

Peristalsis/propulsion is achieved by a circular contraction..is this contraction cranial or caudal to the bolus of food?

Back 48

Cranial

Front 49

What happens caudally to the bolus of food?

Back 49

Relaxtion

Front 50

Peristalsis travels over a long distance, in which direction?

Back 50

Analwards

Front 51

This direction can also be defined as the bolus moving in what direction?

Back 51

Aborally

Front 52

Moving the bolus food in this manner requires a strong reflex called

Back 52

Adaptive relaxation