Human Anatomy and Physiology: Respiratory System

5 Questions

What are the primary functions of the nose and nasal cavity in the respiratory system?

Moisten and warm entering air

Match the following lung volumes with their descriptions:

Tidal volume = Volume of air inspired or expired with each breath Vital capacity = Tidal volume plus inspiratory reserve volume plus expiratory reserve volume Residual volume = Volume of air remaining in the lungs after a maximum expiration Inspiratory reserve volume = Amount of air that can be inspired forcefully after inspiration of the resting tidal volume

What is the common passageway for both the respiratory and digestive systems?

Pharynx

Increased thickness of the respiratory membrane increases the rate of gas diffusion.

False

The _________ transports more oxygen when the partial pressure of oxygen is low.

hemoglobin

Study Notes

The Respiratory System

Components of the Respiratory System

Nose and nasal cavity
Pharynx
Larynx
Trachea
Bronchi
Lungs

Anatomical Division

Upper respiratory tract: nose, nasal cavity, pharynx, and larynx
Lower respiratory tract: trachea, bronchi, and lungs

Functional Division

Respiratory zone: where gas exchange occurs
Conducting zone: where air is conducted to the lungs

Principal Organs

Nose and nasal cavity:
- Divided into external nose and internal nasal cavity
- Functions: provides airway, moistens and warms air, filters and cleans air, serves as a resonating chamber for speech, houses olfactory receptors
Pharynx:
- Common passageway for respiratory and digestive systems
- Passageway for air and food
Larynx:
- Connects pharynx to trachea
- Functions: provides a patent airway, houses vocal cords for voice production
Trachea:
- Flexible tube running from larynx to bronchi
- Functions: serves as an air passageway, cleans, warms, and moistens air
Bronchi:
- Consists of right and left main bronchi, which subdivide into lobar and segmental bronchi and bronchioles
- Functions: conducts air to the lungs
Alveoli:
- Main site for gas exchange
- Type I or Type II
Lungs:
- Paired composite organs located in the thorax
- Composed primarily of alveoli and respiratory passageways
Pleura and pleural cavities:
- Functions: lubrication, movement of lungs, and holding pleural membranes together

Functions of the Respiratory System

Gas exchange
Regulation of blood pH
Voice production
Olfaction
Innate immunity

Respiration

Pulmonary ventilation: movement of air into and out of the lungs
External respiration: movement of oxygen from the lungs to the blood and carbon dioxide from the blood to the lungs
Transport of respiratory gases: transport of oxygen from the lungs to the tissue cells and carbon dioxide from the tissue cells to the lungs

Ventilation

Phases: inspiration and expiration
Inspiration: movement of air into the lungs
Expiration: movement of air out of the lungs

Pressure Changes and Airflow

Changes in volume result in changes in pressure
Air flows from an area of higher pressure to an area of lower pressure

Muscles of Respiration

Diaphragm and external intercostal muscles: contract to increase thoracic volume and decrease pressure
Lung recoil: tendency for an expanded lung to decrease in size due to elastic fibers and surface tension

Pulmonary Volumes and Capacities

Four respiratory volumes: tidal, inspiratory reserve, expiratory reserve, and residual
Four respiratory capacities: vital, functional residual, inspiratory, and total lung

Pulmonary Function Test

Evaluation of lung volume and capacities by spirometry to diagram movement of air as the patient performs various respiratory maneuvers

Control of Respiration

Respiratory center: located in the medulla oblongata and pons
Apneustic center: stimulates the respiratory center
Pneumotaxic center: regulates the respiratory center
Central chemoreceptors: respond to changes in blood pH
Peripheral chemoreceptors: respond to changes in arterial oxygen and carbon dioxide