Respiratory System

What are the two main functions of the respiratory system?

To bring oxygen into the body and remove carbon dioxide

Why do we need oxygen?

Oxygen is required for cellular respiration to produce ATP (energy)

What waste product is produced during cellular respiration?

Carbon dioxide

What mainly drives the urge to breathe?

The buildup of carbon dioxide in the blood

Which body system transports oxygen and carbon dioxide?

The circulatory system

Name four common respiratory diseases.

Asthma, emphysema, COPD, and lung cancer

What are the major functions of the respiratory system?

Deliver oxygen, Remove carbon dioxide, Maintain acid-base balance, Produce speech, Detect odors, Help during coughing and childbirth

What are the two functional divisions of the respiratory system?

Conducting zone and Respiratory Zone

What is the function of the conducting zone?

Moves air, filters it, warms it, and humidifies it.

Does gas exchange occur in the conducting zone?

No

Where does gas exchange occur?

In the respiratory zone

What are the two parts of the nose?

External nose and Nasal cavity

What separates the left and right nasal cavities?

Nasal septum

What bones form the back of the nasal septum?

Perpendicular plate of the ethmoid bone and the vomer

What are the three nasal conchae?

Superior, Middle, Inferior

What do the nasal conchae do?

Increase surface area, Warm air, Humidify air, Filter air

What are the paranasal sinuses?

Air-filled spaces in skull bones.

Functions of the paranasal sinuses?

Warm air, Humidify air, Produce mucus, Lighten skull weight

Which enzyme in nasal mucus kills bacteria?

Lysozyme.

Which cells produce mucus?

Goblet cells.

What type of epithelium lines most of the nasal cavity?

Pseudostratified ciliated columnar epithelium.

What are the three regions of the pharynx?

Nasopharynx, Oropharynx, Laryngopharynx

What passes through the nasopharynx?

Air only

What tonsil is found in the nasopharynx?

Pharyngeal tonsil (adenoid)

What passes through the oropharynx?

Air and food

Which tonsils are found in the oropharynx?

Palatine tonsils and Lingual tonsils

Where does the laryngopharynx lead?

Larynx and Esophagus

What are the three major cartilages of the larynx?

Thyroid cartilage, Cricoid cartilage, Epiglottis

Which cartilage forms the Adam's apple?

Thyroid cartilage.

What is the function of the epiglottis?

Prevents food from entering the trachea during swallowing

What is the glottis?

The opening between the vocal cords.

Which vocal cords produce sound?

True vocal cords.

What are vestibular folds?

False vocal cords.

How many C-shaped cartilage rings support the trachea?

16–20

Why are the cartilage rings C-shaped?

They allow the esophagus to expand during swallowing.

What muscle forms the back of the trachea?

Trachealis muscle

Where does the trachea divide?

At the carina.

What happens if the carina is stimulated?

Violent coughing

The primary bronchi enter the lungs through the ______.

Hilum

What is a bronchiole?

A small airway branching from the bronchi

Do bronchioles contain cartilage?

No

Where does the respiratory zone begin?

Respiratory bronchioles

What structures are included in the respiratory zone?

Respiratory bronchioles, Alveolar ducts, Alveolar sacs, Alveoli

What is an alveolus?

A tiny air sac where gas exchange occurs

Which cells make up 97% of the alveolar surface?

Type I alveolar cells

Function of Type I alveolar cells?

Gas exchange

Function of Type II alveolar cells?

Produce pulmonary surfactant

What does pulmonary surfactant do?

Reduces surface tension and prevents alveolar collapse

What are alveolar macrophages?

Immune cells that remove debris and pathogens

What is the respiratory membrane?

Thin barrier where oxygen and carbon dioxide diffuse

Why is the left lung smaller?

It has a cardiac notch for the heart

What separates lung lobes?

Fissures

Function of pleural fluid?

Reduces friction, Helps lungs stick to chest wall

Which artery carries deoxygenated blood to the lungs?

Pulmonary artery

Which veins return oxygenated blood to the heart?

Pulmonary veins

What does the sympathetic nervous system do?

Bronchodilation

What does the parasympathetic nervous system do?

Bronchoconstriction

What law explains pressure and volume changes during breathing?

Boyle's Law

What happens to pressure when volume increases?

Pressure decreases

What happens to pressure when volume decreases?

Pressure increases

Is inspiration active or passive?

Active

Main muscles used during inspiration?

Diaphragm and External intercostals

During inspiration, the diaphragm moves ______.

Downward

During inspiration, intra-alveolar pressure becomes ______ atmospheric pressure.

Less than

Is quiet expiration active or passive?

Passive

Why does air leave the lungs?

Lung recoil increases pressure above atmospheric pressure

What is eupnea?

Normal quiet breathing

What is hyperpnea?

Forced breathing

What is diaphragmatic breathing?

Deep breathing using the diaphragm

What is costal breathing?

Shallow breathing using intercostal muscles

What is tidal volume (TV)?

Normal air inhaled or exhaled

What is inspiratory reserve volume (IRV)?

Extra air inhaled after a normal breath

What is expiratory reserve volume (ERV)?

Extra air exhaled after a normal breath

What is residual volume (RV)?

Air remaining after maximum exhalation

Where is the respiratory center?

Medulla oblongata

Which brain region fine-tunes breathing?

Pons

What primarily stimulates breathing?

Increased carbon dioxide

Which receptors detect CO₂ and pH?

Chemoreceptors

When does oxygen become a major stimulus for breathing?

When blood oxygen falls below about 60 mm Hg.

Where does external respiration occur?

Between alveoli and pulmonary capillaries

Where does internal respiration occur?

Between blood and body tissues

How do oxygen and carbon dioxide move across membranes?

Simple diffusion

What is Dalton's Law?

Total pressure equals the sum of all partial pressures.

What is Henry's Law?

Gas dissolved in liquid depends on its partial pressure and solubility

What is ventilation?

Air movement into and out of the lungs

What is perfusion?

Blood flow through pulmonary capillaries

What carries most oxygen in the blood?

Hemoglobin in red blood cells

Approximately what percentage of oxygen is dissolved in plasma?

About 1.5%