Chapter 21: Respiratory Function and Gas Exchange(Exam 3)

Flashcards covering concepts related to respiratory function and gas exchange from lecture notes.

Parts of the upper airway

Nasopharynx, oropharynx, laryngopharynx

Structures of the lower airway

Larynx, trachea, bronchi, bronchioles, alveoli

Function of the nasal cavity

Filters, warms, and humidifies air

Vibrissae

Large hairs that filter air in the nose

Role of cilia

Move mucus and trapped particles upward

Type of epithelium lining the trachea

Pseudostratified ciliated columnar epithelium

Location of gas exchange

Alveoli

Type I alveolar cells

Cells involved in gas exchange

Type II alveolar cells

Cells that produce surfactant

Function of alveolar macrophages

Remove debris and pathogens

Anatomic dead space

Air not used in gas exchange

Alveolar dead space

Ventilated but not perfused alveoli

Physiologic dead space

Anatomic + alveolar dead space

Process during inspiration

Diaphragm contracts, pressure decreases, air flows in

Process during expiration

Lungs recoil and air flows out passively

Surfactant

Substance that reduces surface tension in alveoli

Importance of surfactant

Prevents alveolar collapse

Airway resistance

Resistance to airflow in the respiratory tract

Factors increasing airway resistance

Mucus, bronchospasm, decreased radius

Location of highest airway resistance

Nose

Location of lowest airway resistance

Small bronchioles

Lung compliance

Ease of lung expansion

Factors decreasing lung compliance

Aging, fibrosis, chest wall rigidity

Factors increasing lung compliance

Loss of elastic tissue

Neurological control of breathing

Pons and medulla

Pneumotaxic center

Controls breathing rate and ends inspiration

Response of central chemoreceptors

CO2 and pH changes

Response of peripheral chemoreceptors

Low oxygen levels

Hypoventilation

Insufficient air reaching alveoli

Effect of hypoventilation

High CO2 and low oxygen

Hyperventilation

Excessive ventilation causing low CO2

Causes of hypoventilation

Drugs, obesity, muscle weakness

Causes of hyperventilation

Anxiety, fever, high altitude

Function of bronchial arteries

Supply oxygenated blood to lung tissue

Function of pulmonary arteries

Carry deoxygenated blood for gas exchange

Effect of hyperventilation on CO2 levels

They decrease

Effect of low CO2 on oxygen binding

Oxygen binds more tightly to hemoglobin

Affects on distribution of ventilation

Body position

Location of greatest ventilation in upright lung

At the base

Effect of smoking on ciliary function

It is impaired.