Biology for IGCSE & O level - Variation And Selection (Section 5 - No. 13)

In plants adapted to aquatic environments, what is the main function of the extensive air spaces in their leaves?

To store water for dry periods.

To provide buoyancy and assist with gas exchange.

To allow the leaves to grow larger than normal.

To protect the leaves from herbivores.

Air spaces help with buoyancy and facilitate gas exchange in aquatic plants.