Respiratory System

What are the main functions of the respiratory system?

Warming, humidification, filtration of air, gaseous exchange, phonation, and regulating acid-base balance.

Where does warming, humidification, and filtration primarily occur in the respiratory system?

The nasal cavity.

What is hypoxia?

A condition where there is a low or inadequate oxygen supply to cells.

What is the difference between generalized hypoxia and localized hypoxia?

Generalized hypoxia affects the whole body while localized hypoxia affects a specific area.

What is the first process of respiration?

Pulmonary ventilation - the movement of air into and out of the lungs.

Describe internal respiration.

The movement of oxygen and carbon dioxide between the tissue cells and the blood.

What is external respiration?

The movement of oxygen and carbon dioxide between the lungs and the blood.

What is the role of the cardiovascular system in respiration?

Transport of respiratory gases.

What are conducting zones?

Structures that move gases to the exchange sites.

What constitutes the respiratory zone?

Sites for gas exchange such as respiratory bronchioles, alveolar ducts, and alveoli.

What are the upper respiratory tract structures?

Nasal cavity, paranasal sinuses, and pharynx.

Function of the nasal cavity?

To provide the sense of smell and trap foreign particles with mucosa.

What forms the roof and floor of the nasal cavity?

The ethmoid and sphenoid bones form the roof, and the hard and soft palate form the floor.

Describe the function of the conchae in the nasal cavity.

To increase the respiratory mucosal area and enhance air turbulence.

What types of cells are found in the respiratory mucosa?

Pseudo-stratified ciliated columnar epithelium, goblet cells, and sensory nerve endings.

What is the role of goblet cells in the nasal cavity?

Mucus production to moisten the air and trap dust.

What are paranasal sinuses?

Air-filled sinuses that lighten the skull and are prone to infections.

What is the pharynx and its roles?

Connects nasal cavity to larynx and oral cavity to esophagus, accommodating air and food passage.

Name the three sections of the pharynx.

Nasopharynx, oropharynx, laryngopharynx.

What are the types of tonsils found in the pharynx?

Pharyngeal tonsil, tubal tonsils, lingual tonsil, palatine tonsils.

What structures make up the lower respiratory tract?

Larynx, trachea, bronchi, and lungs.

What is the larynx mainly composed of?

Nine cartilages, primarily connected by fibrous membranes.

Functions of the larynx?

Passageway for air, voice production, and preventing food from entering the lower respiratory tract.

What are the unpaired cartilages of the larynx?

Thyroid, epiglottic, and cricoid cartilages.

What are the paired cartilages of the larynx?

The paired cartilages of the larynx are the arytenoid, cuneiform, and corniculate cartilages.

What determines the pitch of the voice?

The angle and protrusion of the thyroid cartilage.

What actions do the vocal cords perform?

Vibrate as air rushes through the glottis to produce sound.

How is speech produced?

Intermittent release of expired air while opening and closing the glottis.

What do the intrinsic muscles of the larynx do?

Alter the position of cartilages, changing vocal fold tension and glottis size.

What are the intrinsic muscles of the larynx?

The intrinsic muscles of the larynx include the thyroarytenoid, cricothyroid, posterior cricoarytenoid, lateral cricoarytenoid, and arytenoid muscles.

What is the trachea's primary function?

Conduct air to and from the lungs without gas exchange.

What changes occur as you move down the bronchial tree?

Changes in cartilage support and epithelial type.

What is the lung lobule composed of?

An arteriole, venule, and terminal bronchiole wrapped in elastic connective tissue.

What function do alveoli serve?

They are the primary sites for gas exchange in the lungs.

What is surfactant and its purpose in the alveoli?

A mixture of phospholipids and lipoproteins that reduces surface tension.

How is carbon dioxide transported in the blood?

Dissolved in plasma, combined with hemoglobin, or as bicarbonate ions.

What is the Haldane Effect?

Deoxygenated blood can carry more carbon dioxide than oxygenated blood.

How does air move into the lungs?

Air moves into the lungs through the process of inhalation, where the diaphragm contracts and expands the thoracic cavity, lowering the pressure inside compared to the outside atmosphere.

What happens during the mechanics of inhalation?

During inhalation, the diaphragm contracts and moves downward, the thoracic cavity expands, and negative pressure is created, drawing air in.

What role does atmospheric pressure play in breathing?

Atmospheric pressure acts as a driving force for air movement; air flows from areas of higher pressure to areas of lower pressure.

How does the pressure gradient affect lung ventilation?

The pressure gradient between the atmosphere and the alveolar pressure determines the flow of air; when alveolar pressure is lower than atmospheric pressure, air flows into the lungs.

What is the function of the pleural cavity during breathing?

The pleural cavity creates a pressure gradient that facilitates lung expansion during inhalation and prevents lung collapse.

What initiates the process of inhalation?

Inhalation is initiated by neural signals from the respiratory centers in the brain that stimulate the diaphragm and intercostal muscles.

What are the two types of breathing?

Quiet respiration and forced respiration.

What muscles are primarily involved in quiet respiration?

Diaphragm and external intercostal muscles.

What is the role of the diaphragm during quiet respiration?

The diaphragm contracts and flattens, increasing the thoracic cavity volume.

How do external intercostal muscles assist in quiet respiration?

They elevate the ribs and expand the chest cavity.

What mechanism drives exhalation?

Exhalation is driven by passive elastic recoil of the lungs and the relaxation of the diaphragm, which increases the pressure in the thoracic cavity, forcing air out.

Define tidal volume (TV).

Tidal volume is the amount of air inhaled or exhaled during normal breathing.

What is the equation for Alveolar Ventilation Rate (AVR)?

Frequency x (Tidal Volume - Dead Space).

What is the role of the sternocleidomastoid muscle in forced respiration?

It elevates the sternum, increasing the volume of the thoracic cavity.

How do the scalenes contribute to forced respiration?

They elevate the first two ribs and assist in enlargement of the thoracic cavity.

What is the function of the pectoralis major during forced respiration?

When the arms are fixed, it helps elevate the ribcage, increasing lung capacity.

What role do abdominal muscles play in forced respiration?

They contract to push the diaphragm upward, aiding in expelling air from the lungs.

Describe the process of forced expiration.

Forced expiration involves the contraction of abdominal muscles and internal intercostals, which push air out quickly and forcefully.

What are the five lung volumes?

Tidal volume (TV), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), residual volume (RV), and anatomical dead space.

What role do chemoreceptors play in respiration?

Monitor CO2, O2, and pH levels in the blood to regulate respiration.

What influences respiratory activity?

CO2, O2, pH levels, voluntary control, and emotional factors.

Define hyperventilation.

Increased breathing rate and depth that exceeds physiological needs, resulting in decreased CO2 levels.