Human Anatomy: Respiratory System Part 1

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Questions and Answers

What is the main function of the respiratory system?

To produce sound

To regulate body temperature

To supply the body with oxygen and dispose of carbon dioxide (correct)

To trap foreign particles

What is the term for the process of drawing gases into the lungs?

Exhalation

Respiration

Inhalation (correct)

Ventilation

What is the function of the conchae in the nasal cavity?

To produce mucus

To regulate blood pH

To detect olfactory receptors

To increase surface area (correct)

What is the term for the layer of cells that secretes mucus and contains cilia?

Respiratory mucosa Signup and view all the answers

What is the function of the olfactory receptors in the nasal cavity?

To contain receptors for smell Signup and view all the answers

What is the term for the process of forcing gases out of the lungs?

Exhalation Signup and view all the answers

What is the function of the mucus in the respiratory system?

To trap contaminants Signup and view all the answers

What is the term for the part of the respiratory system that includes the nose, nasal cavity, paranasal sinuses, pharynx, and larynx?

Upper respiratory tract Signup and view all the answers

What separates the nasal cavity from the oral cavity?

The palate Signup and view all the answers

What is the function of the paranasal sinuses?

To act as resonance chambers for speech and produce mucus Signup and view all the answers

What is the muscular passage from the nasal cavity to the larynx?

The pharynx Signup and view all the answers

What is the function of the adenoids?

To provide defense against foreign materials Signup and view all the answers

What is the function of the tonsils?

To provide defense against ingested or inhaled foreign materials Signup and view all the answers

What is the function of the larynx?

To prevent swallowed materials from entering the lower respiratory tract Signup and view all the answers

What is the function of the epiglottis?

To prevent swallowed materials from entering the lower respiratory tract Signup and view all the answers

What is the inferior region of the pharynx also known as?

Hypopharynx Signup and view all the answers

What type of cartilage is the epiglottis made of?

Elastic cartilage Signup and view all the answers

What is the function of the vestibular folds?

They protect the true vocal cords Signup and view all the answers

What determines the quality of the sound produced by the vocal folds?

The tension, length, and position of the vocal folds Signup and view all the answers

What is the function of the glottis?

It is the opening between the vocal cords Signup and view all the answers

What is the function of the posterior cricoarytenoid muscle?

Vocal abduction Signup and view all the answers

What is the function of the lateral cricoarytenoid muscle?

Vocal adduction Signup and view all the answers

What is the function of the pharynx, oral cavity, nasal cavity, and paranasal sinuses in sound production?

They act as resonating chambers that add quality to the sound Signup and view all the answers

What nerves are responsible for the innervation of the larynx?

Recurrent laryngeal nerves Signup and view all the answers

What is the function of the ciliated mucosa in the trachea?

To beat continuously in the opposite direction of incoming air to expel mucus Signup and view all the answers

What is the name of the internal ridge that forms the separation between the right and left primary bronchi?

Carina Signup and view all the answers

Which of the following is true about the right primary bronchus compared to the left primary bronchus?

It is shorter, wider, and more vertically oriented Signup and view all the answers

What is the function of the hilum of the lung?

To provide access for entry of pulmonary vessels, nerves, and bronchi Signup and view all the answers

What happens to the amount of cartilage and smooth muscle in the bronchial tree as it branches?

Cartilage decreases, smooth muscle increases Signup and view all the answers

What is the function of histamine in the bronchial tree?

To cause bronchoconstriction Signup and view all the answers

What is the main function of the respiratory zone?

To exchange oxygen and carbon dioxide Signup and view all the answers

What is the shape of each lung?

Conical Signup and view all the answers

What is the superior region of the lung called?

Apex Signup and view all the answers

What is the purpose of the pleural fluid?

To lubricate the pleural cavity and minimize friction during breathing Signup and view all the answers

How many lobes does the right lung have?

3 Signup and view all the answers

What is the condition where there is too much fluid in the pleural space?

Pleural effusion Signup and view all the answers

What is the name of the fissure that divides the left lung into 2 lobes?

Oblique fissure Signup and view all the answers

What is the response of pulmonary vessels to hypoxia?

Vasoconstriction Signup and view all the answers

What is the name of the membrane that lines the internal thoracic walls and the lateral surfaces of the mediastinum?

Parietal pleura Signup and view all the answers

What is the name of the arteries that supply oxygenated blood to the lungs?

Bronchial arteries Signup and view all the answers

Study Notes

Organization and Functions of the Respiratory System

The respiratory system consists of an upper respiratory tract (nose to larynx) and a lower respiratory tract (trachea and below).
The conducting portion transports air and includes the nose, nasal cavity, paranasal sinuses, pharynx, larynx, trachea, and smaller airways.
The respiratory portion carries out gas exchange and includes small airways, alveolar ducts, and air sacs (alveoli).

Respiratory System Functions

Supplies the body with oxygen and disposes of carbon dioxide
Filters inspired air
Produces sound
Contains receptors for smell
Removes excess water and heat
Helps regulate blood acidity (pH)

Breathing

Breathing (ventilation) consists of two cyclic phases: inhalation (inspiration) and exhalation (expiration)
Inhalation draws gases into the lungs, and exhalation forces gases out of the lungs

Respiratory Mucosa

A layer of pseudostratified ciliated columnar epithelial cells that secrete mucus
Found in the nose, sinuses, pharynx, larynx, and trachea
Cilia move mucus towards the mouth, and mucus can trap contaminants

Organs of the Respiratory System

Nose
Pharynx
Larynx
Trachea
Bronchi
Lungs – alveoli

Upper Respiratory Tract

Anatomy of the Nasal Cavity

Olfactory receptors are located in the mucosa on the superior surface
The rest of the cavity is lined with respiratory mucosa
Moisturizes air and traps foreign particles
Lateral walls have projections called conchae, which increase surface area
The nasal cavity is separated from the oral cavity by the palate (anterior hard palate and posterior soft palate)

Paranasal Sinuses

Cavities within bones, surrounding the nasal cavity
Include the frontal, sphenoid, ethmoidal, and maxillary sinuses
Function to reduce the weight of the skull, act as resonance chambers for speech, and produce mucus that drains into the nasal cavity

Pharynx (Throat)

Muscular passage from the nasal cavity to the larynx
Three regions: nasopharynx (superior), oropharynx (middle), and laryngopharynx (inferior)

Nasopharynx

Lateral walls have auditory/eustachian tubes that connect to the middle ears
Posterior nasopharynx houses the adenoids

Oropharynx

Middle pharyngeal region
Common respiratory and digestive pathway
Palatine tonsils are located on the lateral wall, and lingual tonsils are at the base of the tongue
Lymphatic organs that provide defense against ingested or inhaled foreign materials

Laryngopharynx

Inferior region of the pharynx
Also called the hypopharynx
Ends at the superior border of the esophagus and the epiglottis of the larynx
Permits passage of both food and air

Larynx (Voice Box)

Short, cylindrical airway that ends in the trachea
Prevents swallowed materials from entering the lower respiratory tract
Conducts air into the lower respiratory tract
Produces sounds
Supported by a framework of nine pieces of cartilage

Larynx

Muscular walls aid in voice production and the swallowing reflex
Glottis is the superior opening of the larynx
Epiglottis prevents food and drink from entering the airway when swallowing

Structures of the Larynx

Vocal cords (vocal folds): vibrate with expelled air to create sound (speech)
Glottis: opening between vocal cords
Inferior ligaments are called vocal folds (true vocal cords)
Superior ligaments are called vestibular folds (false vocal cords)

Sound Production

Intermittent release of exhaled air through the vocal folds
Loudness depends on the force with which air is exhaled through the cords
Pharynx, oral cavity, nasal cavity, and paranasal sinuses act as resonating chambers that add quality to the sound
Muscles of the face, tongue, and lips help with enunciation of words

The Larynx

Voice production: length of the vocal folds changes with pitch, and loudness depends on the force of air across the vocal folds
Intrinsic muscle of the larynx: lateral cricoarytenoid (vocal adduction) and posterior cricoarytenoid (vocal abduction)
Innervation of the larynx: recurrent laryngeal nerves (branch of vagus)

Trachea (Windpipe)

Connects the larynx with the bronchi
Lined with ciliated mucosa
Walls are reinforced with C-shaped hyaline cartilage
At the level of the sternal angle, the trachea bifurcates into two smaller tubes, called the right and left primary bronchi

Primary Bronchi

Right and left primary bronchi
Carina marks the line of separation between the two bronchi
Has cartilaginous C-shaped supporting rings
Right primary bronchus is shorter, wider, and more vertically oriented than the left primary bronchus
Foreign particles are more likely to lodge in the right primary bronchus

Bronchial Tree

Secondary bronchi → tertiary bronchi → bronchioles → terminal bronchioles
With successive branching, the amount of cartilage decreases, and the amount of smooth muscle increases
This allows for variation in airway diameter during exertion and when the sympathetic division is active (bronchodilation)
Mediators of allergic reactions, like histamine, cause bronchoconstriction
Epithelium gradually changes from ciliated pseudostratified columnar epithelium to simple cuboidal epithelium in terminal bronchioles

Conduction vs. Respiratory Zones

Conduction zone: most of the tubing in the lungs, from the nasal cavity to the terminal bronchioles
Respiratory zone: where gas is exchanged, including alveoli, alveolar sacs, alveolar ducts, and respiratory bronchioles

Gross Anatomy of the Lungs

Each lung has a conical shape
Its wide, concave base rests upon the muscular diaphragm
Its superior region, called the apex, projects superiorly to a point that is slightly superior and posterior to the clavicle
Both lungs are bordered by the thoracic wall anteriorly, laterally, and posteriorly, and supported by the rib cage

Lungs

Left lung: divided into two lobes by an oblique fissure, smaller than the right lung, and has a cardiac notch to accommodate the heart
Right lung: divided into three lobes by an oblique and horizontal fissure, located more superiorly in the body due to the liver on the right side

Pleura and Pleural Cavities

The outer surface of each lung and the adjacent internal thoracic wall are lined by a serous membrane called the pleura
The outer surface of each lung is tightly covered by the visceral pleura
The internal thoracic walls, the lateral surfaces of the mediastinum, and the superior surface of the diaphragm are lined by the parietal pleura
The parietal and visceral pleural layers are continuous at the hilus of each lung
The potential space between the serous membrane layers is a pleural cavity
The pleural membranes produce a thin, serous pleural fluid that circulates in the pleural cavity and acts as a lubricant, ensuring minimal friction during breathing

Blood Supply of the Lungs

Pulmonary circulation
Bronchial circulation: bronchial arteries supply oxygenated blood to the lungs, and bronchial veins carry away deoxygenated blood from lung tissue → superior vena cava
Response to hypoxia: pulmonary vessels undergo vasoconstriction, and bronchial vessels undergo vasodilation

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Description

This quiz covers the organization and functions of the respiratory system, including its conducting and respiratory portions. It focuses on the upper and lower respiratory tracts and their components.