Interestingly, although they are all referred to as algae, the red, green and brown algae are classified into three different kingdoms: the protists, chromists and Plantae, respectively. The algae all have cell wall structures and are capable of photosynthesis like our plants on land.nterestingly, although they are all referred to as algae, the red, green and brown algae are classified into three different kingdoms: the protists, chromists and Plantae, respectively. The algae all have cell wall structures and are capable of photosynthesis like our plants on land.
You put documents in a folder for storage; a letter would go in an envelope.
An example of an envelope is what you would seal a letter in before mailing it to someone. 1  a thing that envelops; wrapper; covering. 2  a folded paper container as for a letter, usually with a gummed flap for sealing.  the outer covering of a rigid airship.