9. Knowing what you know about how a substance travels in diffusion, in order for oxygen to leave the alveoli and enter the
blood, there would be a [ HIGHER or LOWER] concentration of
oxygen in the alveoli compared to the blood.

In order for oxygen to leave the alveoli and enter the blood, there would be a higher concentration of oxygen in the alveoli compared to the blood.

Diffusion is the process by which compounds or substances move from a

region of higher concentration to that of a lower concentration. This helps to create an equilibrium in the concentration of the substance to prevent cell death due to shrinking etc,

The alveoli is found in the lungs which is the organ of respiration and the

oxygen present is usually in higher concentration and moves to regions of

low concentration in the blood.

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Higher

Explanation:

Molecules such as oxygen move from a higher concentration to a lower concentration across a semi-permeable membrane. This process is called simple diffusion.

Therefore, for oxygen to leave the alveoli and enter the blood, there would need to be a higher concentration of oxygen inside the alveoli and a lower concentration of oxygen in the blood.