Functions of respiration

Supply blood with 02 and dispose of C02

Four processes of respiration

Pulmonary ventilation, external respiration, transport, and internal respiration

Pulmonary Ventilation

(breathing) movement of air into and out of lungs

External Respiration

02 and C02 exchange between lungs and blood

Transport

02 and C02 in blood

Internal Repiration

02 and C02 exchange between systemic blood vessels and tissues

Conducting zone includes:

Conduits for air to reach sites of gas exchange
Nose, nasal cavity, pharynx, trachea, and bronchi

Respiratory zone includes:

Site of gas exchange
Bronchioles, alveolar ducts, and alveoli

Respiratory Muscles include:

diaphragm, external intercostal, and other muscles

Functions of the nose

Airway for respiration, moistening and warming air, filtering air, resonating chambers for speech, and housing olfactory receptors

The nose consists of

The external nose and the nasal cavity (entirely within the skull)

The nasal cavity consists of:

Olfactory and respiratory mucosa

Nares are:

Nostrils

Nasal Vestibule: location

Nasal cavity superior to nares

Vibrissae are:

Hairs that filter course particle from inspired air

Olfactory mucosa: location and function

Lines superior nasal cavity and contains olfactory recptors

Respiratory Mucosa: location and function

Lines the nasal cavity and contains lysozyme and definsins to destroy bacteria

Superior, middle, and inferior nasal chonchae function

Increase mucosal area, enhance air turbulence, and help filter and moisten air

Paranasal Sinuses: location and function

In frontal, sphenoid, ethmoid, and maxillary bones.
Lighten skull, warm and moisten air , and play a role in resonance of sound.

What is the pharynx?
Location
Includes

Funnel shaped tube of skeletal muscle that connects to the nasal cavity and mouth superiorly and larynx and esophagus inferiorly
Nasopharynx, oropharynx, and laryngopharynx

Nasopharynx

Serves only as an air passageway and contains pharyngeal tonsils

Oropharynx

Air and food passageway that extends inferiorly from soft palate to epiglottis

Laryngopharynx

Air and food passageway that lies posterior to the epiglottis, extends to the larynx, and continues inferiorly with the esophagus

Larynx: location and functions (3)

Attaches to hyphoid bone and opens into laryngopharynx superiorly and is continuous with the trachea inferiorly.
Airway, routes air and food into proper channels, and voice production

Epiglottis

Elastic cartilage that covers the larynx during swallowing

Larynx consists of

Hyaline cartilage, thyroid, cricoid, paired arytendoid, corniculate, cuneiform, and epiglottis.

Voice ligaments: location and composed of

Found in the larynx attached to arytendoid cartilage and thyroid cartilage
Elastic fibers that form mucosal called true vocal cords

What is the glottis? Its function?

The medial opening between voice ligaments.
They vibrate to produce sound as air rushed up from lungs

Vestibular folds form the:
Location
Function

False vocal cords
Superior to vocal folds
No part in sound production and help to close the glottis during swallowing

Speech

intermittent release of expired air while opening and closing the glottis

Pitch

determined by the length and tension of vocal cords

Loudness

depends upon force at which the air rushes across the vocal cords

Chambers of the pharynx, oral, nasal, and sinus cavities....

amplify and enhance sound quality

Sound is shaped into language by

muscles of the pharynx, tongue, soft palate, and lips

What is the trachea and where is it located?

Windpipe. From the larynx to the mediastinum

Composed of what 3 layers

Mucosa, Submucosa, and Adventitia

Mucosa

made up of goblet cells and pseudostratified ciliated epithelium

Submucosa

connective tissue deep in the mucosa

Adventitia

outermost layer made of c shaped rings of hyaline cartilage

Bronchial Tree: Location and includes?

Begins at trachea, ends at terminal bronchioles, and branches from trachea.
Secondary (lobar) bronchi, tertiary (segmental) bronchi, bronchioles, and terminal bronchioles

Respiratory Zone: Location
Respiratory bronchioles lead to

Begins as terminal bronchioles feed into respiratory bronchioles
Alveolar ducts, then to terminal clusters of alveolar sacs composed of alveoli

Alveoli: Amount and Function

Approximately 300 million and account for most of the lungs volume
Provide tremendous surface area for gas exchange

The air blood barrier is composed of

Pulmonary capillaries and alveolar walls and their fused basement membranes

Alveolar Walls

Single layer of epithelial cells that permit gas exchange by simple diffusion

Aveoli are...

Surrounded by fine elastic fibers, contain open pores, and have macrophages that keep their surface sterile

Lungs are found in the

Thoracic cavity, each lung is suspended in its own pleura cavity and connected to mediastinum via lung roots

Each lobe of the lungs contain

bronchopulmonary segments each served by its own artery, vein, and tertiary bronchus

Left lung

Oblique fissure
Divided into two lobe

Right lung

Oblique and horizontal fissures
Divided into three lobes

Lung tissue consists of

air spaces and elastic connective tissue

What are the 2 lung circulations

Pulmonary Network and Bronchial ateries

Pulmonary Network supplies

systemic blood to the lungs for oxygenation

Bronchial ateries

provide systemic blood to lung tissue

The lungs are innervated by

parasympathetic and sympathetic motor fibers and visceral sensory fibers that constrict and dilate airways

What is the pleura?
Parietal pleura?
Viceral pleura?

Thin double layered serosa
Covers thoracic wall, superior diaphragm, and continues around heart between the lungs
Covers external lungs surface and follows its contours and fissures

Inspiration
Expiration

Air flow into the lungs
Gases exit the lungs

Intrapulmonary pressure

pressure in the alveoli that rises and falls with respiration but always eventually equals out with atmospheric pressure

Intrapleural pressure

pressure within the pleura cavity that rises and falls during respiration but is always about 4 mm Hg less that intrapulmonary pressure

Pulmonary ventilation

mechanical process that causes gas to flow in and out of the lungs according to volume changes in the thoracic cavity

Boyles Law

states that at a constant temp. the pressure of gas varies inversely with its volume

During quiet inspiration

diaphragm and intercostals contract, resulting in an increase in thoracic volume, which causes intrapulmonary pressure to drop below atmospheric pressure, and air flows into the lungs

During forced inspiration

accessory muscles of the neck and thorax contract, increasing thoracic volume beyond the increase in volume during quiet respiration

Quiet expiration

passive process that relies mostly on elastic recoil of the lungs as the thoracic muscles relax

Forced expiration

active process relying on contraction of abdominal muscles to increase intrabdominal pressure and depress the rib cage

Air resistance

the friction encountered by air in the air passageways

As airway resistance increases

Gas flow is reduced

Alevolar surface tension due to water in the alveoli acts to

draw the walls of the alveoli together, presenting a force that must be overcome to expand the lungs

Lung compliance is determine by

Distensibility of lung tissue and thoracic cage as well as alveolar surface tension

Respiratory capacities evaluated by

Respiratory volumes and specific combinations of volumes

Tidal volume

amount of air that moves in and out of the lungs with each breath

Inspiratory reserve volume

amount of air that can be forcefully inspired beyond tidal volume

Expiratory reserve

amount of air that can be evacuated from the lungs after tidal expiration

Residual volume

amount of air that remains in the lungs after maximal forced expiration

Inspiratory capacity

sum of tidal and expiratory reserve and is the amount of volume that can be inspired after tidal expiration

Functional residual capcicty

combined residual volume and expiratory volume and is the amount of air that remains in the lungs after tidal expiration

Vital capacity

sum of tidal, inspiratory, expiratory reserve volumes and is the total amount of exchangeable air

Total lung capacity

total of all volumes

Anatomical dead space

volume of the conducting zone conduits and never contributes to gas exchange

Pulmonary function test

evaluates losses in respiratory function using a spirometer to distinguish between obtrusive and restrictive pulmonary disorders

Non respiratory air movements

cause movement of air in and out of lungs but are not related to breathing (coughing, sneezing, crying, laughing, hiccups, and yawning)

Dalton's law

total pressure exerted by a mixture of gasses is the sum of the pressure exerted by each gas in the mixture

Henry's Law

when a mixture of gases in in contact with a liquid each gas will dissolve in the liquid in proportion to its partial pressure

The composition of alveolar gas differs from atmospheric due to

Gas exchange occurring in the lungs, humidification of air due to conducting passages, and mixing of alveolar gas that occurs with each breath

External respiration is

02 uptake, and C02 unloading from hemoglobin in red blood cells

There is a partial gradient between blood in the alveoli and pulmonary arteries because however carbon dioxide moves in the on a gradient that is

steep; blood diffuses quickly from alveoli into blood
other direct; much less steep

The difference in the degree of the gradient of oxygen and carbon dioxide reflects that

carbon dioxide is much more soluble that oxygen in blood

Ventilation profusion coupling ensures

a close match between the amount of gas reaching the alveoli and the blood flow in pulmonary capilaries

Respiratory membrane is

very thin and presents a huge surface area for effcient gas exchange

For internal respiration the diffusion rate for oxygen and carbon dioxide are from external respiration and pulmonary gas exchange

reversed

What is the partial pressure of oxygen in tissues?
Carbon dioxide?

low so that oxygen diffuses readily into tissue
Similar to oxygen gradient but in the reverse direction

What % of oxygen is dissolved in plasma?
Where is the rest taken?

1.5%
Carried on hemoglobin

How many oxygen molecules can be carried on one hemoglobin?

4

Efficiency of hemoglobin oxygen transport

hemoglobin becomes more attracted to oxygen each time it loads and unloads making transport very efficent

At high plasma partial pressures of oxygen
At dramatically low plasma partial pressure of oxygen (vigorous exercise)

Very little oxygen is unloaded
Much more oxygen is unloaded to supply the tissues

What are the influences of hemoglobin's saturation at any given partial pressure?

Temp, blood ph, P C02, and the amount of BPG in blood

What are the ways that carbon dioxide is transported in the blood? (3)

7-10% dissolved is plasma, 20% carried on hemoglobin bound the globin, and 70% is bicarbonate

What is the medulla oblongata's role in breathing?

contains the dorsal and ventral respiratory groups

Dorsal respiratory group
Ventral respiratory group

Neurons that act as a pace setting for breathing
Functions mostly during forced breathing

What is the pon's role in breathing?

Contains the pontine respiratory group

Pontaine respiratory group

modifies the breathing rhythm and prevents overinflation of the lungs through inhibiting the medullary respiratory centers

Chronic Obtrusive Pulmonary Diseases: AKA
Common in patients who?
Results in?

COPD
Smoke
Dyspnea, coughing, frequent pulmonary infections, and respiratory failure

Obtrusive Emphysema
Chronic Bronchitis

Type of COPD: permanently enlarged alveoli and deterioration of alveolar walls
Type of COPD: excessive mucus production as well as inflamation and fibrosis of the lower respiratory mucosa

Asthma: What is is?
Caused by?

causes coughing, dyspnea, wheezing, and chest tightness caused by active inflammation of the airways

Tuberculosis: What is it?
Caused by?
Spread by?

infectious disease caused by bacterium mycobacterium tuberculosis and spread by coughing and inhalation

Lung Cancer: Common?
Correlated with?

It is the most common type of malignancy in both sexes
Smoking

Squamous cell carcinoma

Arises from epithelium of bronchi and causes masses that hollow out and bleed

Adenocarcinoma

Originates in peripheral lung areas as nodules that develop from bronchial glands and alveolar cells

Small cell carcinoma

Contains lymphocyte like cells that form clusters within the mediastinum and rapidly metastasize