The ……..(i) …... very in colour from olive green to various shades of brown depending upon the amount …....(ii)……..

Options

A. (i) red algae (ii) phycobilins
B. (i) green algae (ii) chlorophyll
C. (i) brown algae (ii) chlorophyll
D. (i) brown algae (ii) carotenoids

Answer

To solve the question, we need to fill in the blanks with the appropriate terms related to algae and their pigments.

1. **Identify the type of algae**: The question states that the organisms vary in color from olive green to various shades of brown. Based on the information provided, we know that brown algae (Phaeophyceae) are known to exhibit such color variations. Therefore, the first blank (i) should be filled with "Brown Algae".

2. **Determine the pigment responsible for color variation**: The second part of the question asks what the color depends on. The transcript mentions that the color of brown algae depends on the amount of a specific pigment. The relevant pigments mentioned are chlorophyll and carotenoids, specifically xanthophylls. Since the color variation is primarily due to the presence of carotenoids (which include xanthophyll), we can conclude that the second blank (ii) should be filled with "xanthophyll".

Putting it all together, the completed sentence is:
"The **(i) Brown Algae** vary in color from olive green to various shades of brown depending upon the amount **(ii) xanthophyll**."