Pdbio 305 - Respiratory System

Front 1

The respiratory system consists of what 6 parts of the body?

Back 1

1. Nasal cavity
2. Pharynx
3. Trachea
4. Bronchi
5. Bronchioles
6. Alveoli

Front 2

The respiratory system permits gaseous exchange between what and what?

Back 2

Gaseous exchange between the external environment and the blood

Front 3

There are 5 functions of the respiratory system, what are they?

Back 3

1. Gaseous exchange
2. Sound production
3. Abdominal compression
4. Route for water/heat loss from body.
5. Coughing and sneezing

Front 4

Why is it important that one of the main respiratory functions is a route for water and heat loss from the body?

Back 4

Moistening of inspired air is ESSENTIAL to prevent the alveolar linings form drying out.

Oxygen and carbon dioxide CANNOT diffuse through dry membranes.

Front 5

What are the 3 types of respiration the body performs?

Back 5

1. External respiration
2. Internal respiration
3. Cellular respiration

Front 6

What is 'External Respiration'?

Back 6

Process by which gases are exchanged between the air in the alveoli and blood within the pulmonary capillaries via diffusion.

Front 7

What is 'Internal Respiration'?

Back 7

Process by which gases are exchanged between the blood and the cells.

Front 8

What is 'Cellular Respiration'?

Back 8

Process by which cells use O2 for metabolism and give off CO2 as waste product.

O2 -> Mitochondria
CO2 From Mitochondria -> Blood Vessel (Waste)

Front 9

What is the process from start to finish of the bronchial tree?

Back 9

Trachea -> R/L Primary Bronchi -> Secondary Bronchi -> Tertiary Bronchi -> Bronchioles -> Alveolar ducts -> Alveolar sacs (Many Small Pulmonary Alveoli)

Front 10

How does gas exchange occur with the blood of the circulatory system?

Back 10

Through thin-walled, moistened pulmonary alveoli

Front 11

What is the number of 'pulmonary alveioli' in the lungs and what is the approximate surface area?

Back 11

300 million

6 times the surface area of the body

Front 12

The surfactant in the alveoli is secreted by what kind of cells?

Back 12

Type II alveolar cells

Front 13

Why is a surfactant needed in the alveoli?

Back 13

Lowers the surface tension inside alveolus

Front 14

How are foreign materials removed from the lungs? (What kind of cells do this)

Back 14

Alveolar macrophages

Front 15

What are the mechanics of breathing? What causes air to move in and out of the lungs?

Back 15

Pressure gradient changes

Front 16

What happens during 'INSPIRATION' of the respiratory system? (i.e., diagphram/intercostal muscles/thoracic volume)

Back 16

Diaphragm CONTRACTS and descends.

External Intercostal Muscles ELEVATE

(*Hint - INSPIRATION comes from EXTERNAL sources.)

Thoracic Volume INCREASES

Front 17

What happens during 'EXPIRATION' of the respiratory system? (i.e., diagphram/intercostal muscles/thoracic volume)

Back 17

Diaphragm RELAXES

Internal Intercostal Muscles CONTRACT

Thoracic Volume DECREASES

Front 18

What is 'hypoxia'?

Back 18

A deprivation of oxygen in tissues and organs.

Front 19

What is 'eupnea'?

Back 19

Normal breathing

Front 20

What is 'dyspnea'?

Back 20

Difficult or labored breathing

Front 21

What is 'apnea'?

Back 21

Temporary cessation of respiration that may follow hyperventilation.

Front 22

What is 'Cheyne-stokes'?

Back 22

Periods of DYSPNEA followed by periods of APNEA

DEATH usually occurs close after this starts to occur

Front 23

What is the 'average respiration rate'?

Back 23

12-15 times per minute

Front 24

What is the 'average Oxygen Consumption' rate?

Back 24

250 ml O2 per minute at rest

Front 25

What are the 2 factors that affect airway resistance?

Back 25

Bronchoconstriction
Bronchodilation

Front 26

What are some of the characteristics of 'bronchoconstriction'?

Back 26

DECREASED radius
INCREASED resistance to flow

Allergy induced spasm of airways (histamine induced)

Parasympathetic stimulation may attribute in relaxed situations where demand for airflow is low.

Bronchiolar smooth muscle contraction = INCREASED airway resistance

Front 27

What are some of the characterisics of 'bronchodilation'?

Back 27

INCREASED radius
DECREASED resistance to airflow

Sympathetic stimulation may attribute. Epi/Norepi hormonal control. Occurs when increased demands for oxygen uptake is required for the body.

Front 28

What are the symptoms of 'ASTHMA' and what is it usually caused by?

Back 28

Recurrent attacks of 'DYSPNEA' (difficulty breathing).

Usually via allergic response to plants, animals, food products.

Results in CONTRACTION of the bronchial muscles.

Front 29

What are the symptoms of 'PNEUMONIA'?

Back 29

Acute infection and inflammation of the lungs with exudation (accumulation of fluid)

Front 30

What are the symptoms of 'CHRONIC BRONCHITIS' and what is it usually caused by?

Back 30

Long term inflammation of lower respiratory airways.

Triggered by frequent exposure to irritating cigarette smoke, polluted air or allergens.

Front 31

What are the symptoms of 'EMPHYSEMA' and what is it usually caused by?

Back 31

Collapse of smaller airways and breakdown of alveolar walls.

Caused by excessive release of destruction enzymes (i.e., TRYPSIN) from alveolar macrophages as a defense mechanism.

This is a response to chronic exposure of cigarette smoke or other irritants.

Front 32

There are 8 values usually listed for lung volumes and capacities. What are they and their abbreviations?

Back 32

1. Tidal Volume (TV)
2. Inspiratory Reserve Volume (IRV)
3. Expiratory Reserve Volume (ERV)
4. Residual Volume (RV)
5. Minute Respiratory Volume (MRV)
6. Alveolar Ventilation Volume (AVV)
7. Total Lung Capacity (TLC)
8. Vital Capacity (VC)

Front 33

What is the definition of 'TIDAL VOLUME'?

Back 33

Volume of air moved into/out of lungs during NORMAL breathing (400-500 ml)

Front 34

What is the definition of 'INSPIRATORY RESERVE VOLUME'?

Back 34

Maximum volume beyond the tidal volume that can be inspired in one deep breath (3000 ml)

Front 35

What is the definition of 'EXPIRATORY RESERVE VOLUME'?

Back 35

Maximum volume beyond the tidal volume that can be forcefully exhaled following normal expiration (1100 ml)

Front 36

What is the definition of 'RESIDUAL VOLUME'?

Back 36

Air that remains in the lungs following forceful expiration (1200 ml)

Front 37

What is the definition of 'MINUTE RESPIRATORY VOLUME'?

Back 37

The volume of air moved in normal ventilation in one minute

(MRV = (tidal volume) x (respiratory rate)

**Normal Value = 6000 ml/min

Front 38

What is the definition of 'ALVEOLAR VENTILATION VOLUME'?

Back 38

Volume of air that ACTUALLY ventilates the alveoli.

AVV = {(tidal volume) - (dead air)} x respiratory rate

**Normal Value = 4200 ml/min

Front 39

What is 'dead air'?

Back 39

Portion of the inspired air that does NOT take part in gas exchange. This air fills passageways to ventilate the alveoli.

This is part of the Alveolar Ventilation Volume (AVV)

Front 40

What percentage of the tidal volume is 'dead air'?

Back 40

30%

Front 41

What is the definition of 'TOTAL LUNG CAPACITY'?

Back 41

The sum of the FOUR lung volumes

TLV = TV + ERV + IRV + RV

**Normal Value = ~5700 ml

Front 42

What is the definition of 'VITAL CAPACITY'?

Back 42

Represents the total amount of air that can be exchanged by the lungs.

**Normal Value = ~4600 ml

Front 43

What is a 'spirogram'?

Back 43

The recording of the pulmonary volumes and capacities.

Front 44

There are 6 layers of the respiratory membrane (alveolar capillary membrane)?

Back 44

1. Surfactant
2. Thin Layer of Fluid - WATER
3. Alveolar Epithelium
4. Interstitial Space
5. Capillary Basement Membrane
6. Capillary Endothelium

Front 45

Sometimes newborn babies have collapsed alveolar sacs. Why does this occur?

Back 45

They aren't secreting surfactant

Front 46

There are 4 factors that affect gaseous diffusion across the respiratory membrane. What are they?

Back 46

1. Thickness of respiratory membrane
2. Surface area of the membrane
3. Diffusion coefficient of each gas
4. Pressure difference across membrane

Front 47

How much more soluble is CO2 than water?

Back 47

20x

Front 48

What is the normal pressure difference for O2 in the alveolus?

Back 48

O2 = 104

Front 49

What is the normal pressure of CO2 across the membrane in the alveolus?

Back 49

CO2=40

Front 50

What is the normal pressure DIFFERENCE of O2 when it crosses the membrane and where does it move?

Back 50

O2 = 40 -> 104 (CAPILLARY)

Front 51

What is the normal pressure DIFFERENCE of CO2 when it crosses the membrane and where does it move?

Back 51

CO2 = 45 -> 40 (ALVEOLUS)

Front 52

There are 4 elements involved in the composition of air. What are the elements and what are their normal values in the atmosphere?

Back 52

N2 - 78.6%
O2 - 20.8%
CO2 - 0.04%
H2O - 0.5%

Front 53

What are the values (percentages) of the different elements of air that are located in the alveolus?

Back 53

N2 - 74.9%
O2 - 13.6%
CO2 - 5.3%
H2O - 6.2%

Front 54

Which of the two molecules, oxygen or carbon dioxide IS soluble in water?

Back 54

CARBON DIOXIDE

Front 55

Because 'oxygen' is NOT very soluble in water, what percentage of O2 is dissolved in the BLOOD PLASMA?

Back 55

1-3%

Front 56

What percentage of 'oxygen' is carried by the hemoglobin molecules in the red blood cells?

Back 56

97-99%

Front 57

Where does hemoglobin pick up oxygen and where does it release it?

Back 57

PICK UP = Lungs

RELEASE = Cells

Front 58

The most important determination factor of whether or not oxygen is BOUND or RELEASED is caused by what?

Back 58

Concentration (partial pressure) of oxygen

Front 59

If oxygen makes up about 21% of atmospheric air, it is responsible for 21% of the atmospheric pressure.

This O2 concentration is equal to what amount of mm Hg?

Back 59

21% x 760 mm Hg = 160 mm Hg

Front 60

The PO2 in the lungs is ___ mm Hg, and is _______ than the normal average O2 atmospheric pressure which is ___ mm Hg

Back 60

1. 104 mm Hg
2. LOWER
3. 160 mm Hg = O2 Pressure

Front 61

The PCO2 in the alveolus is ___ mm Hg, and is _______ than the normal average CO2 atmospheric pressure which is ___ mm Hg

Back 61

1. 40 mm Hg
2. HIGHER
3. 0.304 mm Hg (*Don't need to know)

Front 62

1 gram of Hemoglobin (Hb) carries about how many ml of oxygen?

Back 62

1.34 ml Oxygen (O2)

Front 63

15 gm of Hb per 100 ml of blood - 1 gm of Hb carried about 1.34 ml of Oxygen

Back 63

15 gm / 100 ml of blood x 1.34 ml O2 = 20 ml O2 / 100 ml BLOOD

Front 64

Normally ARTERIAL BLOOD is about __% saturated with O2 and VENOUS BLOOD is about __% saturated with O2.

Back 64

1. Arterial Blood = 97%
2. Venous Blood = 75%

Front 65

During exercise ____ oxygen is removed from the blood.

*(More/Less)

Back 65

MORE

Front 66

During exercise, ARTERIAL BLOOD is about __% saturated with O2 and VENOUS BLOOD is about __% saturated with O2.

Back 66

1. Arterial Blood = 97%
2. Venous Blood = 25%

Front 67

What is the most important factor in determining the % Hb saturation?

Back 67

PO2 of the blood

Front 68

True or False:

Hb saturation curve is NOT linear in the relationship with blood PO2.

Back 68

TRUE

Hb saturation is NOT linear. It is S-shaped

Front 69

Under normal conditions only about __% of the O2 is released to the cells in the tissue.

Back 69

25%

Front 70

At a PO2 in the tissues the 'Oxygen-Hemaglobin Saturation' curve is still around __%?

Back 70

75%

Front 71

There are 4 factors that affect the 'Oxygen-Hemaglobin Saturation' curve. What are they?

Back 71

1. pH
2. PCO2
3. Temperature
4. 2,3-Biphosphoglycerate (BPG)
*Present in RBCs

Front 72

What is the 'Bohr Effect'?

Back 72

The factors that can cause the 'Oxygen-Hemaglobin Saturation Curve' to shift to the RIGHT

Front 73

What is the % of Hb saturation when the PO2 is at 40 mm Hg?

Back 73

75% Saturated

Front 74

What is the % of Hb saturation when the PO2 is at 100 mm Hg?

Back 74

97.5% Saturated

Front 75

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is INCREASED PCO2?

Back 75

Shifts to the RIGHT

Front 76

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is INCREASED Body Temperature?

Back 76

Shifts to the RIGHT

Front 77

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is DECREASED pH (increased acidity/decreased basicity)?

Back 77

Shifts to the RIGHT

Front 78

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is DECREASED PCO2?

Back 78

Shifts to the LEFT

Front 79

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is DECREASED Body Temperature?

Back 79

Shifts to the LEFT

Front 80

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is INCREASED pH (decreased acidity/increased basicity)?

Back 80

Shifts to the LEFT

Front 81

What happens to the 'Oxygen-Hemaglobin Saturation Curve' when there is INCREASED '2,3-biphosphoglycerate' (BPG)?

Back 81

Shifts to the RIGHT

Front 82

When PCO2, Acidity (H+), Body Temperature and/or 2,3-biphosphoglycerate (BPG) INCREASE. What is this called? What happens to the 'Oxygen-Hemaglobin Saturation Curve?

Back 82

Called the 'Bohr Effect'

The saturation curve shifts to the RIGHT

Front 83

During exercise, hemoglobin unloads more oxygen and the partial pressure of O2 drops. Which way will the 'Oxygen-Hemaglobin Saturation Curve' shift?

Back 83

RIGHT

(Bohr Effect)

Front 84

Why is it usually not a problem even under abnormal conditions for CO2 to be transported in the blood as a cell uses oxygen?

Back 84

More CO2 can be carried than O2.

Front 85

There are 3 major ways that CO2 can be transported. What are they and what percentage of the time are they utilized by the body?

Back 85

1. Dissolved in blood plasma (7-8%)
2. Carried by Hb (23-25%)
3. As bicarbonate ion (65-70%)

Front 86

Which mechanism of transporting CO2 in the body is the MOST important one and why?

Back 86

As a bicarbonate ion (65-70% of the time)

Can carry more CO2 than the other mechanisms.

Front 87

What is the molecule called when CO2 binds to Hb?

Back 87

Carbaminohemoglobin

Front 88

Hb can also be considered a buffer for what ion?

Back 88

H+

Front 89

What is the 'Chloride Shift' effect? What CO2 transport mechanism is it connected with?

Back 89

Bicarbonate Ion Mechanism

As bicarbonate ions diffuse OUT of the RBC's into the PLASMA and transported to the LUNGS, Cl- diffuses IN from the PLASMA.

This counter-balances the positive charge that would have been left inside the RBC.

Front 90

There are 2 CONTROLS of respiration. What are they?

Back 90

1. Neural Control
2. Chemical Control

Front 91

What is the most important part of the body that is utilized in regulating RESPIRATION?

Back 91

MEDULLA

Front 92

What are the characteristics of the 'Neural Control' center in the respiratory control?

Back 92

Controlled by 'Medullary Respiratory Center' in brain stem

Consists of dorsal/ventral respiratory groups in medulla

Two other centers in the pons that help regulate (apneustic/pneumotaxic).

Front 93

What are the other two centers that are located in the pons that help regulated respiration in the 'Neural Control' respiratory system?

Back 93

Apneustic Center

Pneumotaxic Center

Front 94

These type of NEURONS regulate the main part of inspiration and expiration and are located in the medulla.

Back 94

DORSAL NEURONS

Front 95

What are the characteristics of the 'Dorsal Respiratory Group'?

Back 95

MAJOR rhythm regulator

Consists mainly of inspiratory neurons. Descending fibers stimulate inspiratory muscles.

Front 96

What are the characteristics of the 'Ventral Respiratory Group'?

Back 96

Active when ventilation demands increase.

Contains BOTH inspiratory/expiratory neurons.

Normally INACTIVE during quiet breathing.

Front 97

What does the 'pneumotaxic' center do?

Back 97

Sends impulses to DORSAL neurons to 'SWITCH OFF' inspiratory neurons.

Limit duration of inspiration.

Front 98

What does the 'apneustic' center do?

Back 98

Prevents inspiratory neurons from being 'SWITCHED OFF'

Provides extra BOOST to inspiratory drive.

Front 99

What is the 'Herring-Breuer' reflex, and when does it occur?

Back 99

Helps prevent OVERINFLATION of the lungs

Stretch receptors in lungs are activated by stretching of lungs at LARGE tidal volumes.

Front 100

There are two types of chemoreceptors involved in the 'Chemical Control' system in respiratory control. What are they and where are they located?

Back 100

1. Peripheral Chemorecepters - Located in the CAROTID and AORTIC bodies.

2. Central Chemoreceptors - Located in the MEDULLA.

Front 101

Which is the most important molecule in controlling respiration?

Back 101

CO2

Front 102

In the 'Chemical Control' system in respiratory control, the PERIPHERAL CHEMORECEPTORS are controlled by the concentrations of 2 things. What are the 2 things?

Back 102

1. DECREASED PO2
2. INCREASED H+ CONCENTRATION

Front 103

In the 'Chemical Control' system in respiratory control, the CENTRAL CHEMORECEPTORS are controlled by the concentrations of 1 thing. What is that 1 thing?

Back 103

1. INCREASED PCO2

Front 104

A temporary absence of respiration is known as?

Back 104

Apnea

Front 105

Which two muscles are involved in inspiration?

Back 105

1. DIAPHRAGM
2. EXTERNAL INTERCOSTALS

Front 106

What is the average oxygen consumption of a person at rest?

Back 106

250 ml/min

Front 107

What is residual volume?

Back 107

The air that remains in the lungs following a forceful expiration

Front 108

What is vital capacity?

Back 108

The TOTAL amount of air that can be exchanged by the lungs

Front 109

What % of the atmosphere is O2?

Back 109

20.8%

Front 110

O2 pressure in the alveolus is?

Back 110

104 mm Hg

Front 111

Most CO2 is transported via?

Back 111

BICARBONATE ION

Front 112

Overinflation of the lungs is prevented by what?

Back 112

HERRING-BREUER REFLEX

Front 113

The lack of surfactant in newborn babies is referred to as?

Back 113

RESPIRATORY DISTRESS SYNDROME