algae

definition: 
A simple, non-flowering, and typically aquatic plant of a large assemblage that includes the seaweeds and many single-celled forms. Algae contain chlorophyll but lack true stems, roots, leaves, and vascular tissue.
sentence: 
It is a blue-green alga, a primitive plant of the same class as seaweeds or the green slime seen on rocks and jetties when uncovered by the sea at low tide.
difficulty: 
easy
toefl frequency: 
2
toefl classification: