Respiratory System

Question 0

Functions
Of
Respiratory system

Answer 0

1. Gas exchange
2. Move air in & out of the body-due to muscle contractions
3. Protection–WBCs in lungs, many diseases are airborne
4. Olfaction–smell
5. Speech/sounds

Question 1

What is the respiratory system based on?

Answer 1

Pressure differences

Question 2

Respiratory System

Anatomy

Answer 2

2 lungs
- right lobe (3 sections) - larger than left because of position of heart
- left lobe (2 sections)-lower lung capacity than right lung
Thoracic cavity–closed chamber
Serous membrane - connective tissue- helps creates air pressure
-visceral pleura-on lung
-pleural fluid
-parietal pleural

Question 3

Pathway
Of
Air Flow

Answer 3

• Nostrils
• Nasal Cavity
• Pharynx (throat)
• Larynx (vocal cords) - cartilage
• Trachea - cartilage
• Bronchi (primary, secondary, tertiary) - cartilage
• Bronchioles (controls air coming in & out) - smooth muscle
• Alveoli (air sacs) - where gas exchange occurs - simple squamous epithelium

Question 4

What is Breathing based on?

Answer 4

pressure-greater or less than atmospheric air

Question 5

Characteristics
Of
Inhaling/inspiration

Answer 5

Active process
Muscle contracting
Intercostal muscles - between ribs
-pulls thoracic cavity outward
-diaphragm contracts-when it moves down, it increases air volume in thoracic cavity

Question 6

Atmospheric air pressure

Pressure in lungs

Answer 6

760 mm Hg

Question 7

Boyle’s Law

Answer 7

As volume goes up, pressure goes down (ex: inhalation)

As volume goes down, pressure goes up (ex: exhalation)

Question 8

Characteristics
Of
Exhale/Expiration

Answer 8

Passive process
Muscles relax
Diaphragm moves up, it decreases air volume in thoracic cavity

Question 9

Dalton’s Law of Partial Pressure

Answer 9

In a gas mixture, each gas exhibits it’s own partial pressure.
The total gas pressure is the sum of the partial pressures.

Question 10

Percentages

Of the

4 Gases in the Air we breath

Answer 10

Air 760mmHg
Nitrogen (78%). 597mmHg
Oxygen (21%). 160mmHg
Carbon Dioxide (.033%). 0.25mmHg
Water (varies). ?
_________________________________
Total. 760 mm Hg

Question 11

Diffusion has what effect on pressure?

Answer 11

Goes from higher pressure to lower pressure & vice versa

Question 12

Henry’s Law

Answer 12

Each gas has a Soluability co-efficient
How quickly it can go into a liquid/water environment

CO2 = .57 - most soluable
O2 = .024
N2 = .012 - least soluable

Question 13

Oxygen Transport

Answer 13

2% dissolved in plasma

98% on hemoglobin
Oxyhemoglobin is fully saturated

Question 14

Carbon dioxide Transport

Answer 14

7% dissolved in plasma

23% on hemoglobin
Carbaminohemoglobin

70% as bicarbonate (HCO-3)
Ion in blood plasma

Question 15

Factors that affect O2 unloading

Answer 15

1. Temperature - increase temp.; speeds up chemical process
2. More CO2 release, release more H+; increases O2 unloading
3. Increase in acidity (7.4 pH avg.) (ex. Decrease of pH to 7.2)

Question 16

Examples of breathing disorders

Answer 16

• punctured lung
• mucous build up on bronchioles will effect gas exchange on alveoli
• breathing chemicals, can break down alveoli membrane, which means less gas exchange because less surface area
• fibrosis-less flexible connective tissue develops on lung lining

Question 17

What are the events during Inspiration

Answer 17

• Diaphragm & external intercostal muscles contract
• volume of thoracic cavity increases
• intrapleural pressure becomes more negative
• lungs expand
• intra pulmonary pressure becomes more negative
• air flows into the lungs

Question 18

What are the events of expiration?

Answer 18

• diaphragm & external costal muscles relax
• volume of thoracic cavity decreases
• intrapleural pressure becomes less negative
• lungs recoil
• intra pulmonary pressure rises above atmospheric pressure
• air flows out of lungs

Question 19

What happens during External Respiration?

Answer 19

CO2 diffuses from capillaries into alveoli

O2 diffuses from alveoli into capillaries

Question 20

What happens during Internal Respiration?

Answer 20

O2 diffuses from systemic capillaries into cells

CO2diffuses from cells into systemic capillaries

Depends on:

• available surface area, which varies in different tissues
• Partial pressure gradients
• Rate of blood flow varies

Question 21

Effects of ACH
On
Bronchioles

Answer 21

Decreases airflow

Increased resistance

Question 22

Effects of histamine
On
Bronchioles

Answer 22

Increase airway resistance

Decreased airflow

Question 23

Effects of epinephrine
On
Bronchioles

Answer 23

Dilates bronchioles
Decreases airway resistance
Increases airflow

Question 24

Describe respiratory membrane

Answer 24

Structure-combo of thin epithelial walls of alveolus cells and thin endothelial wall of blood capillary with shared basement membrane. Function-provides surface for diffusion of gases between alveolus & blood in capillary

Question 25

Explain how fluid on alveoli would interfere with gas exchange

Answer 25

Increases the distance over which gases must exchange & slows down exchange (ex: pulmonary edema)

Question 26

How would gas exchange be altered if air that we breathed in contained a partial pressure of 30mm Hg of CO2?

Answer 26

Since more CO2 is on the alveoli, then O2 loading will decrease

Question 27

Why does there need to be a higher pressure difference of partial pressures of O2 in order to unload O2 onto hemoglobin?

Answer 27

Because O2 is larger & less soluble than CO2, so more pressure is needed to force O2 on to hemoglobin. Once one-O2 molecule moves on to hemoglobin, the other 3-O2s follow quickly. This is called cooperative binding.

Question 28

Tidal Volume

Answer 28

500ml Amount of air that enters the lungs during a normal, quiet inspiration. The same volume leaves the lungs during a normal expiration

Question 29

Inspiratory Reserve Volume

Answer 29

3100ml Amount of air inhaled can be increased by more forceful contractions of the diaphragm & external intercostal muscles. (During forced inspiration, the volume of air inspired over & above the tidal volume

Question 30

Expiratory Reserve Volume

Answer 30

1200 ml Amount of air exhaled can be increased by contraction of the internal intercostal muscles, external & internal obliques, & the rectus & transversus abdominis. (During forced expiration, the volume of air expired over & above the tidal volume)

Question 31

Residual Volume

Answer 31

1200 ml Even after the most forceful expiration, some air remains in the lungs. The residual air prevents the lungs from collapsing. Because residual air remains in the lungs at all times, newly inhaled air is always mixed with air that is partially depleted oxygen

Question 32

Vital Capacity

Answer 32

4800 ml Maximum amount of air a person can exhale after taking the deepest breath possible VC = TV + IRV + ERV

Question 33

What is the function of the Type 2 cell in the alveolus?

Answer 33

Produces surfactant, which is a chemical that reduces surface tension of H2O

Question 34

What does respiratory membrane consist of?

Answer 34

1. Alveolar epithelium (type 1 cells)-simple squamous epithelium. Gases move across 2. Basement Membrane - all epithelium has a basement membrane 3. Endothelium of the capillary-simple squamous epithelium. Is in every blood vessel, arteries, capillaries, & veins

Question 35

Describe everything that is happening In Internal Respiration (Cell to blood)

Answer 35

Amount of CO2 released from cells to the body is key ``` 7% CO2 dissolves in plasma 23% CO2 combines with hemoglobin on RBC 70% CO2 combines with H2O, makes carbonic acid H2CO3, interacts with carbonic anhydrase, which breaks into H + HCO3 Chloride shift - HCO3 released into plasma & Cl- goes into RBC ```

Question 36

Describe everything that is happening In Internal Respiration (Blood to cell)

Answer 36

2% O2 in plasma diffuses to cell H+ from break up of carbonic acid combines with hemoglobin Creates O2 + H + Hb O2 carried on hemoglobin 98% O2 on hemoglobin Chloride shift - HCO3 (from RBC to plasma) & Cl- (from plasma to RBC)

Question 37

Describe everything that is happening In External Respiration (Alveoli to blood)

Answer 37

Pressure of O2 is the key 98% O2 combines with hemoglobin on RBC 2%. O2 diffuses into plasma

Question 38

Describe everything happening In External Respiration (Blood to alveoli)

Answer 38

7%. CO2 diffuses from plasma 23%. CO2 from hemoglobin on RBC 70%. Comes from chloride shift, that turns back into carbonic acid, then CO2 + H2O Chloride shift - HCO3 (from plasma to RBC) & Cl- (from RBC to plasma)