Green and brown algae share many common features. both have pigments for trapping sunlight and use photosynthesis for energy. both store their food as sugars. both have cell walls and plant-like bodies. however, their dna suggests that they are not even remotely related to one another. green algae and brown algae show evolution, since they look similar, but are not close relatives.

- Convergent

Explanation :-

Convergent evolution is the process in which the organisms that are not closely related evolve independently in such a way that they acquire similar traits due to similar environment in which they live or the ecological niche that they occupy. Such structures that result from convergent evolution are called as analogous structures, which perform similar function but have different origins. Convergent evolution can be distinguished from parallel evolution in the fact that in parallel evolution similar traits develop in different species which shared a common ancestor and hence, are closely related.

Thus, since the brown and green algae look similar but are not close relatives they show convergent evolution.

Both of them have a nucleus, golgi apparatus, cell membrane, smooth and rough endoplasmic reticulum, lysosome, and ribosomes.