Medical assisting Administrative and clinical procedures (5e) Chapter 29 The respiratory system

After completing this chapter, you will be able to: Explain the functions of the respiratory system, explain the difference between internal respiration and external respiration, describe how the larynx produces voice sounds, list the structures contained within the lungs, describe the coverings of the lungs and chest cavity,...

The Respiratory

System

Learning Outcomes (cont.)

29.1 Describe the structure and function of each organ

in the respiratory system

29.2 Describe the events involved in the inspiration

and expiration of air

29.3 Explain how oxygen and carbon dioxide are

transported in the blood.

Learning Outcomes (cont.)

29.4 Compare various respiratory volumes and tell how they are used to diagnose respiratory problems.

29.5 Describe the causes, signs and symptoms, and

treatments of various diseases and disorders of the

respiratory system.

• Function

– Move air in and out of lungs

• External respiration – in the lungs

• Internal respiration – within the hemoglobin

Organs of the Respiratory System

Organs of the Respiratory System (cont.)

To Diagram

Organs of the Respiratory System (cont.)

Organs of the Respiratory System (cont.)

Organs of the Respiratory System (cont.)

• Trachea

– Tubular organ made of rings of cartilage and

smooth muscle– Extends from the larynx to the bronchi

– Lined with cells possessing cilia

To Diagram

Organs of the Respiratory System (cont.)

• Vocal cords

– Between the thyroid cartilage and the cricoid

cartilage– Glottis~ the opening between the vocal

cords– Upper ~ false cords

– Lower ~ true vocal cords

Organs of the Respiratory System (cont.)

• Bronchial tree – branches off the trachea

Organs of the Respiratory System (cont.)

• Alveoli

– Thin sacs of cells surrounded by capillaries

– “Working tissue”

– Cellular respiration

• Carbon dioxide released into alveoli

• Oxygen released into the blood

To Diagram

The lungs contain connective tissue, the bronchial

tree, nerves, lymphatic vessels, and blood vessels.

Lungs

• Cone-shaped organs

• Right lung – three lobes

• Left lung – two lobes

To Diagram

Apply Your Knowledge

True or False

The nasal conchae supports the mucus membrane and

increases the surface area in the nasal cavity.

The larynx functions for both the respiratory and

The Mechanisms of Breathing

 The diaphragm contracts and flattens

 The intercostal muscles raise the ribs

 Air rich in O2 enters the lungs

Breathing Diagram

Inspiration

The Mechanisms of Breathing

Breathing, or pulmonary ventilation, consists

of inspiration and expiration

 The diaphragm relaxes

 The intercostal muscles lower the

ribs

 Air rich in CO2 exits the lungs

Breathing Diagram

Expiration

The Mechanisms of Breathing (cont.)

The Mechanisms of Breathing (cont.)

• Causes of altered breathing patterns

Apply Your Knowledge

Indicated whether each statement refers to (I) inhalation

or (E) exhalation:

The intercostal muscles lower the ribs

The diaphragm contracts or flattens

The intercostal muscles raise the ribs

The diaphragm relaxes

Air rich in O2 enters the lungs from the atmosphere

Air rich in CO2 exits the lungs

The Transport of Oxygen and Carbon

Dioxide in the Blood

The Transport of Oxygen and Carbon

Dioxide in the Blood (cont.)

• Carbon Dioxide

– Binds to hemoglobin ~ carboxyhemoglobin

– Most carbon dioxide goes into the plasma

– RBCs convert it to carbonic acid used to

regulate the pH of the blood

Apply Your Knowledge

Describe what happens to carbon dioxide in

the blood.

ANSWER: Carbon dioxide can combine with

hemoglobin and form carboxyhemoglobin

Most is converted to carbonic acid by RBCs.

Super!

Respiratory Volumes

• Different volumes of air

move in and out of lungs

with different intensities of

breathing

• Measured to assess

health of respiratory

system

Respiratory Volumes (cont.)

Amount of air that moves in or out of the lungs during a normal breath

Amount of air that can be forcefully inhaled following a normal inhalation

Amount of air that can be forcefully exhaled following a normal exhalation

Respiratory Volumes (cont.)

Amount of air that can be forcefully exhaled after the deepest inhalation possible

Volume of air that always remains in the lungs even after

Apply Your Knowledge

_ Amount of air that moves during

a normal breath.

_ Amount of air that always

remains in the lungs.

_ Total amount of air the lungs

can hold.

_ Amount of air forcefully exhaled

after deepest inhalation

possible.

A Total lung capacity

Common Diseases and Disorders of the

Respiratory System

• Snoring

– Due to vibration of soft tissues when muscles

of the palate, tongue, and throat relax

– Affects approximately 50% of men and 25% of women over the age of 40

– Causes daytime sleepiness

– Severity of snoring

Common Diseases and Disorders (cont.)

Allergic

rhinitis Hypersensitivity reaction to various airborne allergens

bronchial tree become obstructed due

to inflammation

dyspnea

Common Diseases and Disorders (cont.)

follows a cold; one type of COPD

with smoking that damages the alveoli; one type of COPD

Common Diseases and Disorders (cont.)

respiratory system; commonly called the flu

causing hoarseness (dysphonia)Legionnaire’s

disease Acute bacterial pneumonia caused by Legionnaire bacteria that usually

grows in the standing water of air conditioning systems

Common Diseases and Disorders (cont.)

smoking and exposure to second-hand smoke; four types

of lung cancers

cavityPleuritis /

Pleurisy Inflammation of the membranes that cover the lungs, known as

pleura

Common Diseases and Disorders (cont.)

Pneumoconiosis Lung diseases that result from

years environmental or occupational exposure to different types of dust

Pneumonia/

Pneumonitis An inflammation of the lungs that is most often caused by a

bacterial, viral, or fungal infection

around the lungs, which may cause atelectasis

Common Diseases and Disorders (cont.)

Pulmonary

edema A condition in which fluids fill spaces within the lungs, making it

very difficult for the lungs to oxygenate the blood

Pulmonary

embolism A blood clot (embolism) that travels usually from the legs and

blocks an artery in the lungs

Common Diseases and Disorders (cont.)

Common Diseases and Disorders (cont.)

membranes lining the sinuses of the skull

Common Diseases and Disorders (cont.)

caused by various strains of the

Apply Your Knowledge

A collection of air in the chest.

Disorders that limit airflow to the lungs.

An accumulation of fluid in the pleural cavity.

In Summary

29.1 The function of the respiratory system is to move air

in and out of the lungs in a process known as ventilation, respiration, or breathing

The larynx contains the vocal cords, which stretch between the thyroid and cricoid cartilages

The lungs contain connective tissue, the bronchial tree, nerves, lymphatic vessels, and blood vessels

The bronchial tree consists of the primary, secondary, and tertiary branches of the bronchi, the

bronchioles, and the alveoli.

In Summary (cont.)

29.2 During inspiration, the diaphragm contracts and the

intercostal muscles raise the ribs, increasing the space in the thoracic cavity

This decreases the pressure within the cavity so that the air outside the body passively flows into the

thoracic cavity

During expiration, the diaphragm relaxes, pushing up into the thoracic cavity, and the intercostal muscles lower the ribs, forcing the air to flow out of the body

Breathing is controlled by the respiratory center of the brain, located in the pons and medulla oblongata

In Summary (cont.)

29.3 Most of the oxygen in the bloodstream binds to the

hemoglobin within red blood cells, resulting in oxyhemoglobin, although a small amount does not bind

to hemoglobin and remains dissolved in the plasma

Carbon dioxide binds to hemoglobin, resulting in carboxyhemoglobin Most of the carbon dioxide that enters the blood reacts with water in plasma and

cerebrospinal fluid to form carbonic acid As carbonic acid ionizes, it releases hydrogen and

bicarbonate ions, which attach to hemoglobin making its

way back to the lungs to be exhaled

In Summary (cont.)

29.4 Respiratory volumes are measured to check the

health of the respiratory system

The volumes are: tidal volume, inspiratory and expiratory reserve volumes, residual volume, inspiratory capacity, functional residual capacity, vital capacity, and total lung capacity The normal

capacities are found in the chapter

In Summary (cont.)

29.5 The diseases and disorders of the respiratory

system are many and varied, as are the causes and

treatments of these diseases

Many of the more common respiratory disorders with their individual causes and treatments are discussed

in detail in the pathophysiology section of this chapter.

End of Chapter 29

The air of ideas

is the only air

worth breathing

~Edith Wharton