Openstax Anatomy and Physiology 2 Chapter 22

What is the respiratory system composed of?

Structures involved in ventilation (airflow to and from the lungs) and gas exchange

What is the Conducting Zone?

many cavities/tube that conduct air into lungs (no gas exchanged)

What structures of the respiratory system make up the conducting zone?

Nose

Pharynx

Larynx

Trachea

Bronchi

Bronchiole

Terminal Bronchioles

What is the Respiratory Zone?

The area where gas exchange occurs.

Structures that make up the respiratory zone?

Respiratory bronchioles

Alveoli

What are the MAJOR functions of the conducting zone?

- A route for incoming and outgoing air

- Remove debris and pathogens from the

incoming air

- Warm and humidify the incoming air

Air enters the nose through?

The external nares

How is air warmed and humidified?

↑ blood supply under epithelium.

As cool air passes mucus membrane, it is warmed and humidified.

Within the nasal cavity, What projects into the nasal cavity on each side?

superior, middle, and inferior nasal conchae

Paranasal sinuses are

Open into the nasal cavity and are lined with mucus membrane

Are composed of

-Maxillary

-Frontal

-Ethmoid

-Sphenoid

Tears drain through?

Paranasal sinuses to help clean nasal cavity

What is separated into right and left sides in the nasal cavity and is formed anteriorly by cartilage and posteriorly by ther perpendicular plate the the ethmoid and vomer bones?

Nasal Septum

Lines the conducting portion of the respiratory tract?

The respiratory mucosa

What lines the nasal cavity, upper pharynx, trachea, bronchi, and large bronchioles?

Pseudostratified Squamous Epithelium

What lines the smaller bronchioles?

Cuboidal Epithelium

What lines the gas exchange surfaces of the lungs?

Simple Squamous Epithelium

Muscular lined tube lined by a mucous membrane?

Pharynx (throat)

Regions of the Pharynx?

-Nasopharynx

-Oropharynx

-Laryngopharynx

Functions in respiration from internal naris to soft palate?

Nasopharynx

Serves as a passageway for both air and food. From Soft palate to level of hyoid bone?

Oropharynx

Functions in digestion and in respiration, serves as a passageway for both air and food. From level of hyoid bone to larynx?

Laryngopharynx

Passageway that connects the pharynx with the trachea (voice box)?

Larynx

Structures of the larynx

-Thyroid

-Epiglottis

-Cricoid cartilage

-Vocal Cords/ Glottis

Larynx functions: Thyroid Cartilage

Adam's Apple

Larynx Functions: Serves to prevent food from entering the larynx?

Epiglottis

Larynx Functions: Serves to connect the larynx to the trachea?

Cricoid Cartilage

Larynx contains two pair of folds; the lower of which produces sound?

Vocal cords

Composed of ventricular folds, vocal cords, and space between these folds

Glottis

Sound (phonation) production

originates from vibration of the vocal folds

Which vocal cords produce high pitches?

Taunt Vocal Cords

Which Vocal cords produce lower pitches?

Relaxed vocal cords

Clear speech requires articulation of what?

Tongue, teeth, and lips

Speech is amplified and resonated by which structures?

Pharynx, paranasal sinues, oral, and nasal cavities.

Extends from the larynx to the primary bronchi?

Trachea (windpipe)

Trachea is composed of

Smooth muscle and C-shaped cartilage

connects the ends of each c-shaped tracheal cartilage and keeps airway open?

Trachealis muscle

What epithelium lines the trachea?

pseudostratified ciliated columnar epithelium

Structures of the bronchial tree

Bronchi

Bronchioles

lined by pseudo-stratified ciliated columnar epithelium containing mucus producing cells?

Bronchi

Bronchi divide into

bronchioles

structures of the bronchi

Trachea divides into R and L primary Bronchi

R bronchus is more vertical and wider- aspirated objects tend to lodge into it.

Walls of bronchi contain rings of cartilage

Bronchial Tree

Bronchial tree > primary bronchi > secondary bronchi > Tertiary bronchi > Bronchioles > Terminal Bronchioles

Walls contain a thick layer of smooth muscle?

Bronchioles

Structures that are directly involved in gas exchange?

Respiratory Zone

Alveoli

Terminal air sacs that form gas exchange surface of lungs

bronchi > bronchioles > terminal bronchioles

Conducting zone

Respiratory bronchiole > alveolar ducts > alveoli

Respiratory zone

cells of alveoli

type I: function is structural

type II: secrete alveolar fluid to keep alveolar cells moist

alveolar macrophages: (dust cells) are wandering phagocytes

Where does gas exchange occur?

across the respiratory membrane (alveolar -capillary)

Composed of simple squamous epithelium and a basement membrane

Condition characterized by conducting passageway that are extremely sensitive to irritants

responds to irritants by constricting smooth muscle

edema and swelling of the mucosa

increase mucus production

bronchospasms

Asthma

Paired organs

are enclosed and protected by the pleural (serous) membrane

Lungs

Artery that arises from the pulmonary trunk and carries deoxygenated arterial blood to alveoli?

Pulmonary Artery

Nerve that leads to bronchodilation?

Sympathetic

Nerve that when stimulated leads to bronchoconstriction?

Parasympathetic

inner layer that covers the lungs themselves

Visceral pleura

Outer layer that is attached to the wall of the thoracic cavity

Parietal Pleura

Which lung has three lobes?

right lung

Superior, middle, and inferior. Separated by two fissures, horizontal and oblique.

Which lung has two lobes?

Left lung

superior and inferior separated by one fissure, oblique, and a depression, the cardiac notch

Supplies the 3 right lung lobes and 2 left lung lobes?

Secondary Bronchi

Gives rise to branches called tertiary (segmental) bronchi?

The Tertiary Bronchi

tertiary (segmental) bronchi supply segments of the tissue called?

bronchopulmonary segments (surgically important)

Considered to be carcinogenic

can cause lung cancer

children are especially affected?

Second-hand tobacco smoke

The process of bringing air into the lungs?

Inspiration (inhalation)

The movement of air into and out of the lungs depends on pressure changes governed by

Boyle's law

volume of a gas varies inversely with its pressure

expanding of lungs

contraction of diaphragm (75%), external intercostal muscles (25%)

Boyle's Law

A principle that describes the relationship between the pressure and volume of a gas at constant temperature

Low pressure inside the lungs causes air to flow? (Boyle's Law)

Flow into the lungs

During breathing surface tension?

Causes the alveoli to assume the smallest diameter possible.

elastic recoil of the lungs

force responsible for normal resting expiration

surfactant

a phospholipid detergent produced by type II alveolar cells.

allows alteration of surface tension of alveoli & prevents collapse following expiration.

Alveolar macrophages

"dust cells" are wandering phagocytes

Where does gas exchange occur?

Across the respiratory membrane (alveolar - capillary)

What makes up Respiratory membrane?

composed of simple squamous epithelium and a basement membrane through which gas exchange occurs

Asthma

condition characterized by conducting passageways that are extremely sensitive to irritants

airways respond to irritants by constricting smooth muscles along bronchial tree

edema and swelling of the mucosa

increase mucus production

bronchospasms occur periodically and lead to an "asthma attack"

Lungs

paired organs- they are enclosed and protected by the pleural (serous) membrane

Arises from the pulmonary trunk and carries deoxygenated arterial blood to the alveoli?

The pulmonary artery

Stimulation leads to bronchodilation

Sympathetic nerve supply of the lungs

Stimulation leads to bronchoconstriction

Parasympathetic nerve supply of the lungs

inner layer that covers the lungs themselves

Visceral pleura

Outer layer is attached to the wall of the thoracic cavity

Parietal pleura

Has three lobes (superior, middle, inferior) separated by two fissures (horizontal and oblique)?

Right Lung

Has two lobes (superior and inferior) separated by one fissure (oblique) and a depression (cardiac notch)

Left Lung

Secondary Bronchi

supply the 3 right lung and 2 left lung lobes

Tertiary bronchi

give rise to branches called tertiary( segmental) bronchi, which supply segments of lung tissue called bronchopulmonary segments (these segments are surgically important)

Second Hand Tobacco Smoke

carcinogenic (cancer-forming)

can cause lung cancer who are no tobacco users

30% increase of developing lung cancer in non-smokers who live with an individual who smokes.

Children are most affected

Inhalation (inspiration)

The process of bringing air into the lungs

Inhalation occurs when

alveolar (inside lungs) pressure falls below atmospheric pressure.

Contraction of the diaphragm and external intercostal muscles increase the size of the thorax thus decreasing the intrapleural pressure ( boyles law) so that the lungs expand.

Expansion of the lungs decrease alveolar pressure (boyles law) so that air moves along the pressure gradient from the atmosphere into the lungs

Forced Inhalation

accessory muscles of inspiration (sternocleidomastoid, scalenes, and pectoralis minor are also used)

Exhalation (expiration)

The movement of air out of the lungs

Exhalation occurs when

Alveolar pressure is higher than atmospheric pressure.

Relaxation of the diaphragm and external intercostal muscles results in elastic recoil of the chest wall and lungs

which increases intrapleural pressure, decreases lung volume, and increases the alveolar pressure so that air moves from the lungs to the atmosphere

There is also and inward pull of surface tension due to the film of alveolar fluid

Forced Exhalation

occurs when air movement of the lungs is impeded (asthma) and employs contraction of the internal internal intercostals and abdominal muscles

Eupnea

Quiet, easy, or normal breathing

Tidal Volume

air moved in and out of the lungs during normal breathing

Inspiratory Reserve volume

air, beyond tidal volume, that can be inhaled

Expiratory Reserve Volume

air, beyond tidal volume, that can be exhaled

Residual Volume

air, beyond expiratory reserve volume, that cannot be exhaled

Minimal Volume

amount of air trapped in lungs after the lungs collapse

Anatomic dead space

volume of air remaining in conducting passages

pulmonary lung capacities

sum of two or more volumes

Inspiratory Capacity

vital capacity and inspiratory reserve volume