Respiratory System Notes Part 1

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Respiratory System Notes Part 1

I. Overview

A. Function:

Brings about the exchange of oxygen and carbon dioxide between the blood, air, and tissues

B. Organs

Nose

Pharynx

Larynx

Trachea

Bronchi

Lungs - alveoli

C. Respiratory tract

Pathway of air from the nose to the lungs

Air in the respiratory tract are:

cleansed - by hairs, cilia, and mucus

warmed - by heat from the blood vessels

moistened - by the wet surfaces in passageway

Necessary to keep lung tissue healthy

II. Structure

A. Upper Respiratory Tract - Nasal cavities, pharynx, glottis, larynx

1. Nasal Cavity

Description: Hollow canals separated by a septum of bone and cartilage

Function: Filter, warm, and moisten the air

Paranasal Sinuses - Cavities within bones surrounding the nasal cavity

Function of the sinuses

Lighten the skull

Act as resonance chambers for speech

Produce mucus that drains into nasal cavity

Mucous membrane lines nasal cavity

__________________ moves mucous and trapped particles to the pharynx

Contains lateral projections called ______________________

_________________________________________________

Increases air turbulence within the nasal cavity

The nasal cavity is separated from the oral cavity by the palate

Anterior ______________ palate (__________________)

Posterior _______________ palate (___________________)

2. Pharynx - throat

Description: funnel-shaped passageway between the nasal cavity and larynx

Function: Connects nasal and oral cavities to the larynx

Three regions of the pharynx

Nasopharynx - superior region, passageway for air

Oropharynx - where oral cavity joins pharynx, passageway for food and air

Laryngopharynx - inferior region that opens to larynx

Tonsils - located in oropharynx

A lymphatic tissue that protects against inhaled pathogens

3. Epiglottis

Description: flap of tissue that sits at the base of the tongue

Function: prevents food from entering the trachea, or windpipe, during swallowing

4. Larynx

Description: Also called the voice box, contains the vocal cords

Function: produces sound

Vocal cords are elastic tissues that vibrate producing sound as air travels through

The opening or slit in the vocal cords is called the glottis

B. Lower Respiratory Tract - Trachea, bronchi, bronchioles, lungs, alveoli

1. Trachea

Description: known as the windpipe, flexible tube that connects larynx to bronchi

Function: directs air to bronchi

Held open by _________________ hyaline cartilage

Trachea is lined with pseudostratified ciliated columnar epithelial cells

______________________ mucus loaded with dust and other ____________________________--

2. Bronchi

Description: Left and right branched tubes of the trachea

Function: passageway of air to lungs

Bronchi enters the right and left lungs

Bronchi subdivide into smaller and smaller branches called bronchioles

Right bronchus is wider, shorter, and straighter than left

3. Bronchioles

Description: Smallest branches f the bronchi

Function: Bronchioles lead to the alveoli

4. Lungs

Description: paired, cone-shaped organ that occupy the thoracic cavity

Function: contains alveolus where gas exchange occurs

Apex (superior portion) is near the clavicle

Base (inferior portion) rests on the diaphragm

Each lung is divided into lobes by fissures

Left lung - two lobes

Right lung - three lobes

Coverings of the lungs

Visceral pleura covers the lung

Parietal fluid lines the walls of the thoracic cavity

Pleural fluid fills the area between layers of pleura to allow gliding

5. Alveoli (singular: alveolus)

Description: Structures made up of simple squamous epithelium surrounded by blood capillaries

Function: exchange of gas

Respiratory membrane - extremely thin membrane that aids in the rapid exchange of gases

Gas crosses the respiratory membrane by diffusion ​​

Oxygen enters the blood

Carbon dioxide enters the alveoli

Macrophages add protection

________________________________ in alveoli prevents the lung from closing or collapsing

III. Gas Exchange and Transport

A. External Respiration

Exchange of gases between ___________ and ______________________ in the lungs

Blood _________________ the lungs is oxygen-_________________and carbon dioxide-_____________________

____________________________________________________________

The alveoli always has more oxygen than the blood

Oxygen moves by diffusion from an area of high concentration to an area of low concentration

____________________________________________________________

Blood returning from tissues has higher concentrations of carbon dioxide than air in the alveoli

Pulmonary capillary blood gives up carbon dioxide

Blood ___________ the lungs is oxygen-_____________ and carbon-_____________

B. Internal Respiration

Exchange of gases between _______________________

An _________________ to what occurs in the lungs

Carbon dioxide diffuses out of tissue to blood

Oxygen diffuses from blood into tissue

C. Gas Transport

________________________ in the blood

Inside red blood cells attached to _________________________ (oxyhemoglobin [HbO2])

A small amount is dissolved in the plasma