Answer - An increase in the width of Stem
(Was answered before in the community)
Credit goes to [PeachSoda]
Reasoning Why I agreed - Plants can grow in the root tips which shows the progression of growth and thats why you would find a lot more plant cells because it will always keep growing.
Chemical composition and physical properties
Accumulation of substances such as pesticides or other chemicals in an organism
Plants are in the ground with soil
What do you mean by this question exactly?