module 8 the respiratory system

Question 1

Describe the visceral and parietal pleura

Answer 1

1. They cover the lung surface
2. and the inner chest wall
3. They form one continuous membrane forming a sealed envelope surrounding the lungs.

Question 2

What generates the subatmospheric pressure in the airless space between the pleura membranes?

Answer 2

• oppositely directed recoil forces of the lungs and chest wall.
• lungs pull in
• chest wall pulls out

Question 3

What supplies the alveoli and participates in gas exchange?

Answer 3

1. The pulmonary circulation.
2. the bronchial system also supplies the lungs, but does not supply the alveoli or participate in gas exchange

Question 4

what is responsible for the normal difference between alveolar gas and arterial blood oxygen pressures?

Answer 4

• a small amount of deoxygenated bronchial system venous blood mixes with oxygenated blood in the pulmonary veins, creating a small anatomical shunt, this is responsible for the difference

Question 5

what type of innervation does the lung recieve?

Answer 5

• only autonomic
• consisting of sympathetic (adrenergic) and parasympathetic (cholinergic), and the nonadrenergic, and noncholinergic (NANC) systems.
  *

Question 6

What is the parasympathetic system responsible for?

Answer 6

airway smooth muscle resting tone

Question 7

what causes bronchoconstriction?

Answer 7

Cholinergic stimulation

Question 8

what causes bronchodilation?

Answer 8

adrenergic stimulation

Question 9

What do B2 - adrenergic agonist (stimulators) and cholinergic antagonist (blockers) drugs do?

Answer 9

both elicit bronchodilation and reduced resistance to airflow

Question 10

How does sympathetic stimulation of airway smooth muscle occur?

Answer 10

Indirectly through adrenal gland secretion of circulating epinephrine.

Question 11

Sensory afferent nerves from the lung are__________ in origin

and include __________, __________,and ______________

Answer 11

1. parasympathetic
2. slowly adapting stretch receptors
3. rapidly adapting irritant receptors,
4. C-fibers

the last two are extremely important in defense of the airways because they evoke powerful reflexes that limit penetration of harmful substances into the respiratory tract.

Question 12

List 4 processes of the respiratory system

Answer 12

1. pulmonary ventilation
2. external respiration
3. transport of respiratory gases
4. internal respiration

Question 13

list the three major functions of the respiratory system

Answer 13

1. continuous supply of O2 for metabolic activities in body cells
2. removal of CO2 from body cells
3. regulation of the pH of the blood

Question 14

pulmonary ventilation

Answer 14

1. breathing
2. consists of breathing in (inhalation) and breathing out (exhalation)

Question 15

external respiration

Answer 15

1. exchange of gases (oxygen and carbon dioxide) between the blood and the lungs

Question 16

how are respiratory gases transported?

Answer 16

1. in the red blood cells and blood plasma

Question 17

internal respiration

Answer 17

• exchange of gases (oxygen and Carbon dioxide) between the blood and tissue cells

Question 18

What two zones comprise the respiratory system?

Answer 18

1. conducting zone (macroscopic) - passageways for conduction of air - nose, pharynx (throat), larynx (voice box), trachea, bronchi, and terminal bronchioles
2. Respiratory Zone (microscopic) - consists of sites involved with the exchange of oxygen and carbon dioxide - respiratory bronchioles, alveolar ducts, alveoli

Question 19

list the functions of the nose (conducting zone)

Answer 19

1. airway for respiration
2. moistens and warms air\
3. cleans and filters unwanted particles
4. aids in speech
5. provides a site for the olfactory receptors (for smell)

Question 20

external nares

Answer 20

anterior portion of each nostril is called the vestibule, contains hairs

Question 21

nasal cavities

Answer 21

1. nose separated into right and left halves by the nasal septum
2. three bony projections called conchae are located on the lateral walls of the nasal cavities; these increase the surface area
3. rich supply of blood that warms and moistens air
4. mucus to trap particles

Question 22

internal nares

Answer 22

1. posterior openings that provide a connection between the nose and the pharynx (throat)

Question 23

paranasal sinuses

Answer 23

beside nose

maxillary

frontal

ethmoidal and

sphenoidal sinuses provide sites for mucus drainage

lighten the skull

warm and moisten air and provide chambers for speech resonance

Question 24

pharynx

Answer 24

throat

• consists of three regions

1. nasopharynx
2. oropharynx
3. laryngopharynx

nasopharynx - air passageway

oropharynx and laryngopharynx - food and air passageway

Question 25

Larynx

Answer 25

voice box contains vocal chords connects pharynx to trachea provides an open passageway for air epiglottis, which covers the opening of the larynx closes off the larynx during swallowing

Question 26

trachea

Answer 26

1. Windpipe 2. passageway 3. cleans, warms moistens 4. c shaped rings of cartilage

Question 27

bronchi

Answer 27

1. Trachea branches into two tubes 2. left bronchus and right bronchus 3. lead to left and right lung 4. bronchi clean, warm, and moisten air 5. provide passageway

Question 28

terminal bronchioles

Answer 28

passageway into the respiratory zone

Question 29

respiratory bronchioles

Answer 29

formed from branchings of terminal bronchioles

Question 30

alveolar ducts

Answer 30

1. respiratory bronchioles lead into alveolar ducts 2. alveolar ducts lead into clusters of alveoli

Question 31

alveolar air sacs

Answer 31

1. 300 million alveoli in each lung lot of surface area for exchange of gasses 2. clusters called alveolar sacs

Question 32

what are two important cell types found in the alveoli?

Answer 32

1. **Type 1 alveolar cells (simple squamous epithelium)** provide the site for gas exchange between the capillaries and the alveoli 2. **Type ll alveolar cells (septal cells)**: produce surfactant a compound that prevents the alveoli from collapsing, reduces surface tension between fluid molecules inside the alveoli so they do not adhere to each other and collapse 3. **Macrophages (dust cells)** wander around cleaning up foreign material

Question 33

how much do the lungs weigh and why

Answer 33

1 kg, 2.2 pounds because they consist of many air spaces

Question 34

hilus

Answer 34

area in each lung where blood vessels, lymphatic vessels, nerves and the bronchus enter and leave the lung

Question 36

cardiac notch

Answer 36

1. area where the heat snuggles into the left lung

Question 37

bronchopulmonary segments

Answer 37

1. lobes of both lungs divided into bronchopulmonary segments, each segment has its own artery and vein

Question 38

lobules

Answer 38

*

Question 39

pleura

Answer 39

1. sac that covers each lung

Question 40

serous membrane of the pleura consists of two layers

Answer 40

* visceral layer * parietal layer visceral layer hugs lung surface including area between lobes parietal layer lines the thoracic chest (wall and upper surface of the diaphragm)