Assertion: kelp's pneumatocyst | /r/CapableOf | gather more light
Facets:
value: for photosynthesis
type: PURPOSE
Source sentences:
text: What makes this macroalgae unique besides the ability to grow to heights of up to 200 feet, is that there are airbladders known as a pneumatocyst that helps the plant float near the surface and gather more light for photosynthesis while shading out competitors.