Produces vocal sounds

Helps with sense of smell

Helps regulate blood pH

Process of exchanging gases between the atmosphere and body cells

Refers to the way an organism acquires energy; oxygen required to produce energy

Respiration consists of the following events:

Respiration consists of the following events:

Ventilation or breathing; allows gas exchange in lungs

Respiration consists of the following events:

Gas transport in blood and exchange with body cells

Respiration consists of the following events:

Process of ATP production in mitochondria, which uses oxygen to harness energy and gives off carbon dioxide

Organs of the respiratory system can be divided into 2 tracts:

Lower respiratory tract consists of ...

Upper respiratory tract consists of...

provide openings for air to enter and leave nasal cavity

Openings are protected from particles by internal hairs

Hollow space behind the nose

Separated into left and right portions by the nasal septum

curl in from lateral walls of cavity

Upper portion contains ______for sense of smell

_______ sweep mucus toward pharynx, where it is swallowed

_____ are destroyed in stomach; prevents infection

______ produce mucus, which traps dust and pathogens

Functions in conduction of air; warms, moistens, and filters incoming air

Air-filled spaces in the maxillary, frontal, ethmoid, and sphenoid bones of the skull

Open into the nasal cavity

Mucous membrane lining is continuous with the lining of the nasal cavity

Reduce weight of skull

Resonate voice

due to infection or allergic reaction, may result in blockage of sinus drainage, causing sinus pressure and headache

Space posterior to the nasal cavity, oral cavity, and larynx

Passageway for food and air

Aids in sound production

3 portions of pharynx:

Inferior to oropharynx; continuous with larynx and esophagus

Superior to soft palate; air passage; contains openings to auditory tubes

Posterior to mouth, inferior to nasopharynx; passageway for food and air

An enlargement in the airway superior to trachea, and anterior and slightly inferior to laryngopharynx

Moves air in and out of tracheaHouses vocal cords

Composed of a framework of muscles and cartilages bound by elastic tissue

Largest cartilage; thyroid gland covers lower part

Below thyroid cartilage

Central portion of flap-like epiglottis

3 pairs of small cartilages:

Regulate vocal cord tension for speech and close larynx for swallowing

Upper (vestibular) folds

No sound production

Help close airway during swallowing

Lower folds

Vocal sounds

Sound created as air is forced between them, vibrating them

Flexible cylindrical tube, 2.5 cm in diameter, 12.5 cm in length

Extends downward anterior to the esophagus

A procedure that cuts an opening in the trachea, to insert a tube for air exchange; done, for example, if an object is lodged in the larynx or trachea

____diffuses from the blood to alveoli

Soft, spongy, cone-shaped organs in the thoracic cavitySeparated from each other by heart and mediastinum

Region on medial surface of each lung through which bronchus and large blood vessels enter

Double-layered serous membrane surrounding lungs

Potential space between visceral and parietal pleura

Inner layer of serous membrane; attached to surface of lung

Outer layer of serous membrane; lines thoracic cavity

Movement of air from outside of the body into the bronchial tree and the alveoli

One inspiration + the following expiration = a_______

Force that moves air into the lungs

At sea level, equals 760 millimeters of mercury (mm Hg)

Pressure and volume of gases are inversely proportional

If pressure inside the alveoli (intra-alveolar pressure) decreases, atmospheric pressure pushes air into the airways

This occurs during normal, resting inspiration, as the phrenic nerves stimulate the diaphragm to contract downward

Volume of thoracic cavity increases, which decreases the pressure from 760 mm Hg to 758 mm Hg

In response to pressure difference, air rushes into thoracic cavity

Diaphragm and external intercostal muscles enlarge the size of the thoracic cavity

Lung expansion is aided by surface tension in the pleural cavity

Surfactant reduces surface tension in the alveoli, to help lung expansion

Requires contraction of several other muscles, to enlarge thoracic cavity even more

Pectoralis minors, sternocleidomastoids, scalenes are used

Normal resting expiration:

lung tissues and abdominal organs occurs, as tissues return to their original shape at the end of inspiration

Normal resting expiration:

develops on the moist surfaces of the alveolar linings shrinks alveoli

a _____, that does not involve muscle contraction

Due to contraction of internal intercostal and abdominal muscles

Increased abdominal pressure forces diaphragm into a higher position, which pushes more air out of lungs

Respiratory Volumes and Capacities

Volume of air moved in or out of the lungs during a respiratory cycle

500 mL

Respiratory Volumes and Capacities

Maximum volume of air that can be inhaled at the end of a resting inspiration

3,000 mL

Respiratory Volumes and Capacities

Maximum volume of air that can be exhaled at the end of a resting expiration

1,100 mL

Respiratory Volumes and Capacities

Volume of air that remains in the lungs even after a maximal expiratory effort

1,200 mL

Respiratory Volumes and Capacities

Maximum volume of air that can be exhaled after taking the deepest breath possible: VC = T V + I R V + E R

4,600 mL

Maximum volume of air that can be inhaled following exhalation of resting tidal volume: I C = T V + l R V

3,500 mL

Volume of air that remains in the lungs following exhalation of resting tidal volume: F R C = E R V + R V

2,300mL

Total volume of air that the lungs can hold: T L C = V C + R V

5,800mL

Some air entering respiratory tract during breathing does not reach functional alveoli; these are called_____

Air in respiratory tract that remains in conduction structures, and does not reach alveoli

Air in respiratory tract that reaches nonfunctional alveoli, such as alveoli associated with capillaries with poor blood flow; this occurs occasionally

Total of anatomical and alveolar dead space

Anatomic dead space = ______ (about 150 mL/breath)

Air movements other than breathing are called ____

Some clear the air passages, as in coughing and sneezing

Some express emotions, as in laughing and crying

Usually result from reflexes, but sometimes they can be started voluntarily

Nonrespiratory Air Movements

Normal breathing is a rhythmic, _____ act that continues when a person is unconscious

Groups of neurons in the brainstem that control breathing

Initiate impulses that travel on cranial and spinal nerves, causing inspiration and expiration

Adjust rate and depth of breathing

Main respiratory areas:

contains 2 groups of neurons:

Ventral respiratory group: Sets basic rhythm of breathing

Dorsal respiratory group: Modifies activity of ventral group

Main respiratory areas:

help set rhythm of breathing by limiting duration of each inspiration

In any mixture of gases, each gas contributes a portion of the total pressure

Amount of pressure each gas contributes to the total pressure Proportional to its concentration

____ is 21% O2

_____760 mm Hg

A number of factors affect the rate and depth of breathing:

are usually the Pco2 and H+ ion concentration

In ventral part of medulla oblongata

Mainly monitor pH in the brain

Low blood Po2 does not have much effect on them

H+ ions do not cross blood-brain barrier well

CO2 crosses blood-brain barrier, and binds to H2O to produce H2CO3

H2CO3 dissociates to release these ions are detected by the

Mainly sense changes in blood Po2

In carotid and aortic bodies

Decreased Po2 causes an increase in breathing rate and tidal volume, leading to an increase in alveolar ventilation

Usually does not cause a major response, until Po2 decreases to about 50% of normal value

Helps regulate depth of breathing

As lung tissues stretch during inspiration, stretch receptors are stimulated

Sensory impulses travel over vagus nerve to respiratory areas

Duration of inspiratory bursts is then shortened• Prevents overinflation of the lungs during forced breathing

Sites of the vital process of gas exchange between the air and the blood

_____macrophages help to clean alveoli

Blood transports___ and ___ between the lungs and the body cells

As the gases enter the blood, they ___ in the plasma or chemically combine with other substances