Hello Marshall!

Good question! 

Most plants take in other elements through their roots from soil. Your cellular chemical reactions, are not very different from plant cells and their reactions (with the exception of photosynthesis, which we cannot do). The minerals in the soil, especially nitrogen, phosphorus, and potassium are very important for growth of plants. Can you think of why your cells would need these same elements? Or perhaps why we consume calcium, sodium, chlorine or magnesium? Your answer may explain why plants need these minerals for their cellular work too.

Hello Soren,

Very good question! The answer is very simple. Like most cells in your body (there are exceptions) plant cells also prefer neutral pH- neither acidic nor basic. Halfway between acids and basic is the pH 7. This is where most chemical reactions work best.

But like, everything in your body, there are exceptions. Can you think of one place in your body where acidic environment works better? In the same way, there are plants that grow in acidic soils, whose normal cellular environment is acidic, and so all their reactions work better at that acidic environment. 

Basic cell environment is not as favored in plants as acidic, because many elements do not dissolve well in basic solutions. 

Hello Brynna,

Those are good questions!

My research is not so much about the evolution of plants, but more about how they work- their physiology. But perhaps your other mentors may be able to answer this question better. Most evolutionary studies on plants are studies on how they adapt to a new or changing habitat, how their genes change during evolution, and how they emerge as a new species in time. 

I have been studying plants since 1978 when I started my undergraduate work. So it has been long 45 years.

We only work with testing hypotheses, and not proving a scientific theory. A scientific theory only emerges after a very long time and after tons of data have supported the hypothesis. When a hypothesis has been supported by multiple data across the world, and it is no longer an ambiguity, it becomes a scientific theory. The word "theory" in English is thus very different from the word "theory" in science. 
So we all mostly work towards finding data to support our hypothesis. 

The hardest experiment for me was with an enzyme called cholesterol oxidase. This enzyme likes water (hydrophilic), and the chemical it works on -cholesterol- does not like water (hydrophobic). I had a tough time bringing them together.