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Which are the smallest green plants? What is their size? Are they easily grown?
Question Date: 2014-03-02
Answer 1:

That's an easy question for me. The smallest green plants are blue green algae, and they have only 1 cell. - Oops! I was wrong. Wikipedia says "blue green algae" are actually a kind of bacteria that get energy from photosynthesis. But they're not plants, because plants and animals all have a nucleus in every cell. Bacterial cells don't have a nucleus.

Here's one of the answers from google.com for "smallest green plant":

Fresh Water Green Algae (Chlamydomonas genus). They are unicellular - the size of only 1 cell (less than 25 micrometers long)! They have a nucleus, thylakoids (special membranes inside the cell) and chloroplasts - which is where photosynthesis takes place. It is believed that Chlamydomonas is the ancestor to green plants.


Chlamydomonas can swim, with its 2 long flagella. I just heard a scientific talk about Chlamydomonas flagella, and the speaker said the swimming is sort of like a breast stroke. They were doing research about how well Chlamydomonas grew, if the 2 flagella were different lengths.

But 'Chlamydomonas' might not the best answer, either, because Wikipedia says plants are multicellular organisms of the kingdom, Plantae. Chlamydomonas and Paramecium and other 1-celled organisms with a nucleus are in the kingdom Protista.

The next answer I find is that duckweeds are the smallest flowering plants. I can't find anything about smallest green plants - Plantae - that don't flower. Here's a nice site with pictures of duckweeds and tiny colored candy sprinkles, which are about the same size:


On the other hand, the Tree of Life web project says green algae are plants, so that brings me back to Chlamydomonas as a good answer. Here's the link:

green plants

McCourt is the first person listed on that web page, and we worked together at the National Science Foundation a few years ago! I've copied him on this email.

Can you grow the smallest green plant? I think it would be hard to grow it without getting contamination from bacteria and other organisms that would kill it, though maybe you could get a 'mixed culture' with the smallest green plant and some other stuff. I think the answer is the same for either Chlamydomonas or duckweed.

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