22 1-8

Question 1

Some functions of the respiratory system aside from the four processes of respiration?

Answer 1

Speech, laugh, cry, smell, pH, BP reg via angiotensin II (RAAS)

Question 2

*Four processes of respiration

Answer 2

1. Pulmonary ventilation (breathing - air moves in/out of lungs, gases continuously refreshed.)
2. External respiration (O2 diffuses from the lungs to the blood, co2 diffuses from the blood to lungs)
3. Transport of respiratory gases (O2 is transported from the lungs to the tissue cells of the body, co2 is transported from the tissue cells to the lungs)
4. Internal respiration (O2 diffuses from blood to tissue cells and co2 diffuses from tissue cells to blood)

***respiratory sys is only responsible for first two processes

Question 3

*Identify the organs forming the respiratory passageway(s) in descending order until the alveoli are reached.

Answer 3

Nose, Nasal cavity, Paranasal sinuses, pharynx, larynx, trachea, bronchi + smaller branches, lungs, alveoli.

Question 4

Nose function

Answer 4

Airway for respiration, moisten and warm air, filter/clean air, resonating chamber for speech, houses olfactory receptors

Question 5

Paranasal sinus function

Answer 5

(Frontal, ethmoidal, maxillary, sphenoidal) Lighten skull, warm and moisten air

Question 6

Pharynx function

Answer 6

Passageway for air and food. Also houses tonsils so exposes immune sys to inhaled air. (“throat”)

Question 7

Larynx function

Answer 7

Provide air passageway, route air/food into proper channels. Also houses vocal folds so voice production. (“voicebox”)

Question 8

Trachea function

Answer 8

Air passageway, cleans/warms/moistens incoming air

Question 9

Bronchial tree function

Answer 9

Air passageway connecting trachea with alveoli, cleans/warms/moistens air.

Question 10

Alveoli function

Answer 10

Main site of gas exchange. Also, surfectant which reduces surface tension/prevents lung collapse.

Question 11

Lung function

Answer 11

Houses respiratory passages smaller than the main bronchi.

Question 12

Pleurae function

Answer 12

Produce lubricating fluids and compartmentalize lungs.

Question 13

*Respiratory (functional) zone

Answer 13

Actual site of gas exchange; composed of: respiratory bronchioles, alveolar ducts, alveolar sacs, alveoli, all microscopic structures

Question 14

*Conducting (structural) zone

Answer 14

Includes all other respiratory passageways - fairly rigid conduits for air to reach gas exchange sites. Also cleanse/humidify/warm air.

nose/nasal cavity/paranasal sinuses/pharynx/larynx/trachea

R/L primary bronchi, secondary bronchi, tertiary bronchi, bronchioles, terminal bronchioles

Question 15

Nasopharynx

Answer 15

Posterior to nasal cavity. Only an air passageway (above where food enters, uvula moves up when swallowing). Contains pharangeal tonsil

Question 16

Oropharynx

Answer 16

Posterior to oral cavity, both food and air pass through. Palatine tonsils embedded in lateral walls. Lingual tonsils on posterior surface of tongue.

Question 17

Laryngopharynx

Answer 17

Posterior to epiglottis, extend to larynx where it is continuous with the larynx. Food and air pass.

Question 18

Epiglottis function

Answer 18

Projects upward when air is flowing, during swallowing the larynx pulls upward and epiglottis tips to cover the laryngeal inlet.

Question 19

Valsalva’s maneuver

Answer 19

During abdominal straining, the glottis closes to prevent exhalation and ab muscles contract causing intraabdominal pressure to rise.

Question 20

*Structure of the trachea

Answer 20

16-20 C-shaped rings or hyaline cartilage.

Layers from innermost to outermost:
mucosa (pseudostrat ciliated columnar epithelium),

submucosa (areolar CT with blood vessels/nerves/glands),

hyaline cartilage,

adventitia (elastic CT)

Question 21

What travels on the mucociliary escalator?

Answer 21

mechanism involving ciliary action and flow of mucus from bronchioles, through the bronchi and trachea to the larynx, by which particulate matter (especially alveolar macrophages) is removed from the respiratory tract.

Question 22

Bronchial tree consists of?

Answer 22

Air passageways in the lungs that branch and branch again. From primary bronchi to terminal bronchi.

Question 23

*Structural changes as the conducting tubes become smaller? (structure of bronchial tree)

Answer 23

Cartilage rings give way to plates of cartilage then no more cartilage in the bronchioles.

Epithelium type changes - psuedostrat columnar –> columnar –> cuboidal in terminal bronchioles.

Smooth muscle amount increases as the conducting tubes get smaller, bronchioles have a complete layer.

Question 24

• Stucture of respiratory membrane? 6

Answer 24

Consists of: Capillary, alveolar walls and their fused membranes.

Primarily Type I alveolar cells (single layer squamous) surrounded by thin basement membrane.

Scattered amid the type I are type II alveolar cells which secrete surfactant and antimicrobial proteins.

External surfaces are covered with pulmonary capillaries.

bound by elastic fibers,

have open alveolar pores between alveoli,

have alveolar macrophages.

Question 25

*How does the respiratory membrane structure contribute to function?

Answer 25

Thin membranes for exchange

And caps to exchange to.

Alveolar pores allow for equal air pressure.

Surfactant decreases surface tension.

Elastic fibers allow for recoil

Shape gives surface area for diffusion

Question 26

Describe the innervation of lung structures by the ANS.

Answer 26

Through pulmonary plexus… Para/sym constrict/dilate, plus visceral sensory fibers.

Question 27

Describe the gross structure of the pleurae

Answer 27

Thin, double layered serosa. Parietal lines the thoracic wall, superior surface of diagphram and continues around the heart between the lungs. Visceral covers the external lung surface.

Question 28

Describe the gross structure of the lungs

Answer 28

Occupy the thoracic cavity except mediastinum.

1. Each lung is suspended within its own pleural cavity and connected to themediastinum by vascular and bronchial attachments called the lung root.
2. Each lobe (L has 2, R has 3 lobes) contains a number of broncho-pulmonary segments each served by is own artery/vein/tertiary bronchus.
3. Lung tissue consists largely of air spaces with the balance comprised of mostly stroma/elastic tissue.
4. Two circulations: pulmonary network carries systemic blood to the lungs for oxygenation, bronchial arteries provide blood to the lung tissue.

Question 29

Aside from gas exchange, Type I cells are involved in?

Answer 29

Blood pressure regulation via angiotensin conerting enzyme (ACE)

Question 30

Type II cells secrete?

Answer 30

Surfactant, a mixture of phospholipids and proteins which coats alveolar surfaces and decreases surface tension created by water’s hydrogen bonding.

Question 31

Alveolar macrophages (dust cells)

Answer 31

Dead ones are continously swept up by the ciliary current of superior regions and carried away to the pharynx then swallowed.

Question 32

*Anatomic properties that keep the lungs inflated?

Answer 32

Transpulmonary pressure - the difference in Ppul - Pip

Elasticity of chest wall

Question 33

*List and describe several protective mechanisms of the respiratory system.

Answer 33

Nasal cavity: Hair catches debris, shape of nasal conchae creates air turbulence, mucus traps debris and kills with defensing and lysozyme, ciliated cells move mucus with debris to be swallowed, sneeze reflex

Uvula: Closes off nasopharynx inlet, prevents food from entering nose

Epiglottis: Covers laryngeal inlet. If food does get in then cough reflex

Cilia: moves mucus containing particulates out of the lungs to be swallowed.

Question 34

Atelectasis

Answer 34

Partial or complete collapse of a lung. Occurs when a bronchiole becomes plugged - alveoli absorb all their air and collapse. Also happens from a chest wound

Question 35

Pneumothorax

Answer 35

The presence of air or gas in the pleural cavity, causing collapse of the lung

Question 36

Lung landmarks

Answer 36

Root (vascular and bronchial attachments to mediastinum), lobes, costal surfaces, apex, base.

Hilum - indentation on mediastinal surface, pulmonary and systemic vessels/bronchi/lymphatic vessels/nerves enter/leave lungs.

Cardiac notch - concavity in L lung that accommodates the heart

Bronchopulmonary segments - pyramid shaped, R-10, L8-10, each is separated by CT and served by its own artery and vein.

Stroma - Mostly elastic CT

Question 37

*Factors that keep alveoli open/closed

Answer 37

OPEN
Surfactant
Transpulmonary pressure
Alveolar interdependence (Kohn pores/pressure eq)

COLLAPSE
Surface tension
Elastic recoil of lungs