Main Points 1

larynx to the main bronchi

The trachea extends from the ___?

C-shaped cartilage rings

________? reinforce the trachea and keep the trachea patent.

respective lungs , smaller

The right and left main bronchi run into their ________, within which they subdivide into ______ and ______ passageways.

respiratory bronchioles, alveolar ducts, alveolar sacs, and finally alveoli

The terminal bronchioles lead into respiratory zone structures: ?

alveoli

Gas exchange occurs in the _____, across the respiratory membrane.

decreases and is finally lost

As the respiratory conduits become smaller, the amount of cartilage _____?

mediastinum in the thoracic cavity.

The lungs, the paired organs of gas exchange, flank the ______?

pleural cavity

Each multilobed lung occupies its own ___?

elastic connective tissue stroma.

The lungs are primarily air

passageways/chambers, supported by an ___?

deoxygenated , systemic circulation

The pulmonary arteries carry _____ blood returned from the _______ to the lungs.

oxygenated

The pulmonary veins return newly _____ blood back to the heart to be distributed throughout the body.

bronchial arteries

The ________ provide the nutrient blood supply of the lungs.

parietal pleura , visceral pleura

The ______ lines the thoracic wall and mediastinum; the ______ covers external lung surfaces.

Pleural fluid

______ reduces friction during breathing movements.

alveoli

Intrapulmonary pressure is the pressure within the _____.

pleural cavity;

Intrapleural pressure is the pressure within the ____?

higher , lower

Gases travel from an area of ____ pressure to an area of _____ pressure.

Inspiration

______ occurs when the diaphragm and external intercostal muscles contract, increasing the dimensions of the thorax.

intrapulmonary and atmospheric pressures are equalized.

As the intrapulmonary pressure drops, air rushes into the lungs until the _____?

Expiration

________ is largely passive, occurring as the inspiratory muscles relax and the lungs recoil.

gases flow from the lungs.

When intrapulmonary pressure exceeds atmospheric pressure _____?

Friction , decreases

_____ in the air passageways causes resistance, which _______ air passage and causes breathing movements to become more strenuous.

midsize bronchi.

The greatest resistance to air flow occurs in the _____?

reduce alveolar size and collapse the alveoli.

Surface tension of alveolar fluid acts to ______?

lack of surfactant

Premature infants have problems keeping their lungs inflated owing to the _____ in their alveoli, resulting in infant respiratory distress syndrome (IRDS).

late

Surfactant formation begins ____ in fetal development.

elasticity , flexibility

Total respiratory compliance depends on _____ of lung tissue and ______ of the bony thorax.

more difficult.

When compliance is impaired, inspiration becomes ____?

tidal, inspiratory reserve, expiratory reserve, and residual.

The four respiratory volumes are _____?

vital, functional residual, inspiratory, and total lung.

The four respiratory capacities are ___?

respiratory volumes and capacities.

Spirometry measures ____?

air-filled volume (about 150 ml)

Anatomical dead space is the _______ of the conducting passageways.