The external covering of diatoms are made up of, while slime molds have cell walls containing. diatoms are because they make food through photosynthesis, while slime molds are because they eat decaying plant matter
When Sarah performed this experiment, she changed the levels of nitrogen in order to observe the changes in the morphological features of the plant.
All of the characteristics of the plant that she observed were dependent on multiple different things, but the level of nitrogen was an independent variable that she was changing at her will.
Answer:
expansion
The process where by things expand when they come in contact with heat