Respiratory System. Primary Function – Gas Exchange Secondary Functions – Speech – pH...

Respiratory System

Respiratory System

• Primary Function

– Gas Exchange

• Secondary Functions

– Speech

– pH regulation of internal environment

• Anatomical Divisions

– Conducting pathways

– Respiratory regions

• sites of gas exchange

• Conducting Pathways

– Upper respiratory tract

• Nasal cavity

• Pharynx

• Nasal Cavity

– Functions

• warms air

• humidifies air

• filters air

–Features of Nasal Cavity

•Conchae

•Ciliated epithelial mucosa

• Nasal cavity communicates with nasal sinuses

• Pharynx

(refer to digestive system notes)

• Pharynx

– Functions

• food and air pathways

• resonating chamber for voice

• swallowing

– 3 divisions

• Nasopharynx

• Oropharynx

• Laryngopharynx

• Structural features of pharynx

– Lined with a stratified squamous epithelium

– Skeletal muscle in wall

• Additional structural features

– Eustachian tube opening

– uvula

– tonsils

• Lower Respiratory Tract

– Larynx

– Trachea

– Bronchi

– Bronchioles

• Larynx

• Larynx

• Structure of the Larynx

• Structure of the Larynx

– Cartilages

_

Epiglottis

_

Epiglottis

Arytenoid

_

Epiglottis

ArytenoidCorniculate

_

Epiglottis

ArytenoidCorniculate

Cricoid_

Epiglottis

ArytenoidCorniculate

CricoidThyroid

Epiglottis

ArytenoidCorniculate

CricoidThyroid

Cuneiform

• Structure of the Larynx

– Cartilages

• Structure of the Larynx

– Cartilages &

• Structure of the Larynx

– Cartilages & ligaments

• Structure of the Larynx

– Cartilages & ligaments

– Muscles

• Structure of the Larynx

– Cartilages & ligaments

– Muscles &

• Structure of the Larynx

– Cartilages & ligaments

– Muscles & bone

• Structure of the Larynx

– Cartilages & ligaments

– Muscles & bone

– Lined with a mucous membrane

goblet cell cilia mucus

• Other Features of Larynx

• Other Features of Larynx

–Ventricular folds (‘false vocal folds’)

• Other Features of Larynx

–Ventricular folds (‘false vocal folds’)

– Vocal folds

• Other Features of Larynx

–Ventricular folds (‘false vocal folds’)

– Vocal folds

• Other Features of Larynx

–Ventricular folds (‘false vocal folds’)

– Vocal folds

– Glottis

• Primary Function of the Larynx

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• Primary Function of the Larynx

– Sound production

• Primary Function of the Larynx

– Sound production

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Cricothyroid Muscle

Cricothyroid Muscle

• Primary Function of the Larynx

– Sound production

• Secondary Functions of the Larynx

– Prevents food & drink from entering lower respiratory tract

•ventricular folds and vocal folds

• Secondary Functions of the Larynx

– Prevents food & drink from entering lower respiratory tract

•ventricular folds and vocal folds

• Secondary Functions of the Larynx

– Prevents food & drink from entering lower respiratory tract

•ventricular folds and vocal folds

•epiglottis

• Trachea (‘Windpipe’)– General

features• 1 inch diameter

• 4-5 inches long – 1st inch in neck

– Composed of 15-20 “C” rings

– Rings linked by annular ligaments

• Bronchi

• Bronchi (singular: bronchus)

• Bronchi (singular: bronchus)

– Primary

• Bronchi (singular: bronchus)

– Primary

• to lungs

• Bronchi (singular: bronchus)

– Primary

• to lungs

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• to lobes of lungs

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• to lobes of lungs

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• to lobes of lungs

– Tertiary

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• to lobes of lungs

– Tertiary (segmental)

• Bronchi (singular: bronchus)

– Primary

• to lungs

– Secondary (lobar)

• to lobes of lungs

– Tertiary (segmental)

• to bronchopulmonary segments of lungs

• Bronchioles

• Bronchioles

– Branch off of tertiary bronchi

• Bronchioles

– Branch off of tertiary bronchi

– Less than 1 mm in diameter

• Bronchioles

– Branch off of tertiary bronchi

– Less than 1 mm in diameter

– Smooth muscle in walls

• Bronchioles

– Branch off of tertiary bronchi

– Less than 1 mm in diameter

– Smooth muscle in walls

• Bronchioles

– Branch off of tertiary bronchi

– Less than 1 mm in diameter

– Smooth muscle in walls

• exhibit bronchoconstriction

• Bronchioles

– Branch off of tertiary bronchi

– Less than 1 mm in diameter

– Smooth muscle in walls

• exhibit bronchoconstriction & bronchodilation

• Terminal Bronchioles

• Terminal Bronchiole

– Last bronchioles before alveoli

• Terminal Bronchioles

– Last bronchioles before alveoli

– Deliver air to lung lobules

Review:

• Anatomical Divisions of Respiratory System

– Conducting pathways

– Respiratory regions: sites of gas exchange

•respiratory bronchioles

•alveoli

• Respiratory Bronchioles

– have alveoli

• Alveoli

• Alveoli (singular: alveolus)

• Alveoli (singular: alveolus)

–Sites of gas exchange

• Alveoli (singular: alveolus)

–Sites of gas exchange

• Alveoli (singular: alveolus)

–Sites of gas exchange

–Form the respiratory membrane with alveolar capillaries

• Alveoli (singular: alveolus)

–Sites of gas exchange

–Form the respiratory membrane with alveolar capillaries

• Alveoli (singular: alveolus)

–Sites of gas exchange

–Form the respiratory membrane with alveolar capillaries

–Secrete surfactant

• Structure of Lungs

–

• Structure of Lungs

– Alveoli

– Bronchi and Bronchioles

– Reticular CT with lots of elastic fibers

– Blood vessels and nerves

• Pleural Cavities

• Pleural membranes

– Visceral pleura

– Parietal pleura

• Pulmonary Ventilation

– Movement of air into and out of the alveoli

• Pulmonary ventilation can be explained by:

1. Boyle’s law: P ~ 1/V2. And the basic concept

that a given volume of air will move from a region of high air pressure into a region of low air pressure

• Ventilation Steps

– Inspiration (quiet or forced)

– Expiration (quiet or forced)

–Muscles of quiet inspiration

•Diaphragm

•External intercostals

• Why does air enter the lungs when these muscles contract?

–Muscles of forced inspiration

–Pect. Minor

– Serratus anterior

– Sternocleidomastoid

–Muscles of quiet expiration

•None!

–Muscles of forced expiration

–Internal intercostals

–Abdominal muscles

• Asthma Video

• Gas Exchange Video

• Bronchoscopy

• Respiration Video