Answer:
a) epigenetic change.
Explanation:
Epigenetic is referred to changes BESIDES the changes in the genetic changes. It means, not related to mutations but to chemical changes such as methylation, acetylation, ubiquitylation, phosphorylation, that can interfere with the genetic expression. Chromatin modification is another way of epigenetic change.
They could improve the experiment that they made by adding another variable such as: watering the plants with fresh water. This way they could have a better comparison how plants grow based on the type of water they are exposed with.
Answer:
Walls are thin.
Inner surface is moist.
Tissues are filled with blood vessels.
Exposed to air
Explanation: