A plant can open or close its stomata in response to environmental conditions. ... A. During a rainstorm, stomata can be opened to absorb additional water through osmosis. B. During a drought, stomata can be closed to prevent excessive water loss through transpiration.
Density = mass / volume. therefore, something with a greater density either has a larger mass or a smaller volume. Think of density as how compressed something is: more "stuff" (mass) or a smaller "space" (volume) will make whatever that material is more compressed.
non-disjunction is a pathological event that occurs during the second anaphase in meiosis when sister chromatids are not separated. As a result one of the resulting cells will have 1 extra chromosome and the other will be 1 short. An example of a non-disjunction that can occur in humans is Down syndrome that has a frequency of about 1/1000 people. It is caused by the non-disjunction of the 21st pair of chromosomes.
