Which statement describes toddler development regarding the lungs?

Which statement describes toddler development regarding the lungs?

• A. Lungs continue to develop more terminal bronchioles and alveoli to meet the increasing needs of oxygen demand
• B. The musculature of their lungs is fully developed
• C. They experience a loss of passive immunity
• D. The heart is the primary driver of oxygen delivery

Answer: (A)

During toddler growth the lungs keep developing more gas-exchange units. Specifically, the formation of additional terminal bronchioles and alveoli expands the surface area available for oxygen uptake and carbon dioxide removal, matching the rising oxygen needs of a growing child and increased activity. The respiratory muscles aren’t yet fully developed at this stage, so their strength continues to improve with age. Passive immunity changes involve the immune system, not lung structure, and while the heart supports oxygen delivery, it isn’t the driver of lung development itself.

During toddler growth the lungs keep developing more gas-exchange units. Specifically, the formation of additional terminal bronchioles and alveoli expands the surface area available for oxygen uptake and carbon dioxide removal, matching the rising oxygen needs of a growing child and increased activity. The respiratory muscles aren’t yet fully developed at this stage, so their strength continues to improve with age. Passive immunity changes involve the immune system, not lung structure, and while the heart supports oxygen delivery, it isn’t the driver of lung development itself.