Question

Look at the following image, and name the types of algae that would be found at each depth:

• A. 150-200m - Brown algae; 100-150m - Green algae; 50-100m - Red algae
  
  
• B. 150-200m - Red algae; 100-150m - Brown algae; 50-100m - Green algae
• C. 150-200m - Green algae; 100-150m - Red algae; 50-100m - Brown algae
• D. 150-200m - Brown algae; 100-150m - Red algae; 50-100m - Green algae

Answer 1

The correct option is B 150-200m - Red algae; 100-150m - Brown algae; 50-100m - Green algae

Green algae possess the pigment chlorophyll, which mainly absorbs blue and red light, and themselves, appear green. Brown algae contain the pigment fucoxanthin, which absorbs blue-green and yellow-green lights and appear brown. Red algae contain phycobilins, which primarily absorb blue light and appear red. Thus, red algae are found deepest, green algae at the uppermost layers, and brown algae intermediate between these.