3.1 exchange surfaces Flashcards
What is the role of surfactant in the lungs
maintain surface tension so the alveoli does not get too over stretched
Why is a baby’s first breath difficult
large change in atmospheric pressure as the lungs are filled with fluid
What happens to the diaphragm during inspiration
contraction
What happens to the diaphragm during expiration
relaxation
What happens to the external intercostal muscles during inspiration
contract
What happens to the internal intercostal muscles during inspiration
relax
What happens to the external intercostal muscles during expiration
relax
What happens to the internal intercostal muscles during expiration
contract
What happens to the rib cage during inspiration
up and out
What happens to the rib cage during expiration
down and in
What happens to the thoraic volume during inspiration
increases
What happens to the thoraic volume during expiration
decreases
What happens to the intrapulmonary pressure during inspiration
decreases
What happens to the intrapulmonary pressure during expiration
increases
What happens to the air movement during inspiration
pressure falls below atmospheric pressure so air is drawn inside
What happens to the air movement during expiration
pressure goes above the atmospheric pressure so air moves out