1.2.7 Mechanics of breathing

• What are the two phases of the mechanics of breathing?

  Inspiration and expiration
• What happens to the diaphragm during expiration?

  Relaxes and returns to dome shape
• Match the respiratory structure with its function:

  Nose and nasal cavity ↔️ Filters, warms, and humidifies air

  Pharynx ↔️ Passageway for air and food

  Larynx ↔️ Contains vocal cords
• The pharynx serves as a passageway for both air and food.

  True
• During expiration, the diaphragm relaxes and the pressure inside the lungs increases.


  True
• During inspiration, the volume of the thoracic cavity increases.


  True
• Air moves into the lungs during inspiration because the pressure inside the lungs is lower than atmospheric pressure.


  True
• Bronchioles are smaller branches of the bronchi that lead to the alveoli
• During inspiration, the pressure inside the lungs decreases
• What is the primary action of the diaphragm during exhalation?

  Relaxes and returns to dome shape
• Match the process with the corresponding changes in volume, pressure, and air movement:

  Inhalation ↔️ Volume increases, pressure decreases, air flows into lungs

  Exhalation ↔️ Volume decreases, pressure increases, air flows out of lungs
• The larynx contains the vocal cords and allows air passage
• Arrange the following structures in the order that air passes through them during inhalation:

  1️⃣ Bronchioles

  2️⃣ Alveoli

  3️⃣ Trachea

  4️⃣ Bronchi
• The intercostal muscles are located between the ribs
• The volume of the thoracic cavity decreases during exhalation.


  True
• What happens to air movement during exhalation?

  Flows out of the lungs
• What do chemoreceptors detect in the blood to regulate breathing?

  O2, CO2, and pH
• Why do males generally have larger lung volumes than females?

  Larger body size
• How is carbon dioxide primarily transported in the blood?

  Bicarbonate ions
• During exhalation, the thoracic cavity's volume decreases
• What is the primary function of the nose and nasal cavity in the respiratory system?

  Filters, warms, and humidifies air
• What is the role of the trachea in the respiratory system?

  Transports air to and from lungs
• Gas exchange in the lungs occurs in the alveoli.


  True
• Outline the steps of inhalation in the respiratory system:

  1️⃣ Diaphragm contracts and flattens

  2️⃣ Intercostal muscles contract, lifting rib cage

  3️⃣ Thoracic cavity volume increases

  4️⃣ Lung pressure decreases below atmospheric pressure

  5️⃣ Air rushes into the lungs
• During exhalation, the pressure inside the lungs increases above atmospheric pressure
• Match the muscle with its action during inhalation:

  Diaphragm ↔️ Contracts and flattens

  Intercostal muscles ↔️ Lift rib cage up and out
• Stretch receptors in the lungs prevent over-inflation by signaling the respiratory center to reduce breathing rate
• Gas exchange in the lungs occurs in the alveoli.

  True
• During inspiration, the diaphragm contracts and becomes flatter
• During expiration, the pressure inside the lungs increases above atmospheric pressure
• What is the function of the trachea?

  Transports air to and from lungs
• What happens to the volume of the thoracic cavity during inspiration?

  Increases
• Steps involved in the process of inhalation

  1️⃣ Diaphragm contracts and flattens

  2️⃣ Intercostal muscles contract, lifting rib cage

  3️⃣ Volume of thoracic cavity increases

  4️⃣ Pressure inside lungs decreases

  5️⃣ Air rushes into the lungs
• Air is expelled from the lungs during exhalation due to increased pressure inside the lungs.


  True
• The pharynx serves as a passageway for both air and food.


  True
• The bronchi divide the trachea into the left and right lungs
• Which muscle contracts to draw air into the lungs during inhalation?

  Diaphragm
• What happens to the diaphragm and intercostal muscles during exhalation?

  Relax
• The respiratory center in the brainstem controls the rate and depth of breathing.


  True
• Match the factor with its influence on lung volume:

  Age ↔️ Lung volume decreases

  Exercise ↔️ Increases lung capacity