Exchange of Gases in the Lungs (AQA A-Level Biology): Quizzes
📚Quizzes
Practise the questions
10 questions from this quiz
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Practise the questions
10 questions from this quiz
Where does gas exchange occur in mammals?
Where does gas exchange occur in mammals?
At the epithelium of the alveoli
What is the diameter range of alveoli?
What is the diameter range of alveoli?
100-300 m
Which features are essential for effective gas exchange surfaces?
Which features are essential for effective gas exchange surfaces?
Thin, large area, well-ventilated
Approximately how many alveoli does each human lung contain?
Approximately how many alveoli does each human lung contain?
300 million
What is the combined surface area of all alveoli in both lungs?
What is the combined surface area of all alveoli in both lungs?
Around 70 m
What makes up the alveolar walls?
What makes up the alveolar walls?
Single layer of epithelial cells
What is the width range of pulmonary capillaries?
What is the width range of pulmonary capillaries?
7-10 m
How long do red blood cells spend in contact with the alveolar wall?
How long do red blood cells spend in contact with the alveolar wall?
Approximately 0.75 seconds
In which direction does oxygen move during gas exchange?
In which direction does oxygen move during gas exchange?
From alveolar air into blood
What type of process is gas exchange in the alveoli?
What type of process is gas exchange in the alveoli?
Simple diffusion down gradients