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<u>Appropriate</u><u> </u><u>Answer</u><u>:</u></h3>
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Nucleus is the control centre of the cell and manages all the cellular activities taking place inside the cell. It consists of four parts :-
- Nuclear membrane,
- Nucleoplasm,
- Chromatin material and
- Nucleolus.
The Chromatin material(Condensed - Chromosome) stores the cell's DNA which is transmitted to next generation.
This evidence suggest that all three living creatures that are mentioned have a common ancestor, even though they have been split into different types of groups of living organism millions of years ago.
Science suggests that all of the living organisms on the planet have a common ancestor. Since we are talking about a common ancestor that lived few hundred million years ago, the living organisms split into different groups, and they do not resemble each other nowadays. The fruit fly is an insect, and the humans and mice are mammals, so they are into totally different groups, and it is easy to see by the genetic evidence that they are very distantly related, but the humans and mice are much more closely related because they belong to the same super family, and their connection is much more recent.
In the case of liquid droplets, including water, surface tension is the factor, which is accountable for their shapes and configuration. Though can easily be malformed, the droplets of water seem to be pulled into a spherical shape due to the cohesive forces of the surface layer.
In the non-existence of other forces, involving gravity, the drops of almost all the liquids would be almost spherical.
Grasshoppers have no ears, instead they use an organ called the tympanum located in the first segment of their abdomen, whereas humans take in sound waves through the ear canal until they reach the eardrum. The eardrum picks up the vibrations and then transmits them to tiny bones in the middle of the ear, the bones pass the vibrations to the inner ear (which is filled with liquid) and the cochlea.
Hope I could help.