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.
The answer would be, if I understand correctly, skeletal and smooth muscle tissue both help the body move, and give the body form. The skeletal structure give the body structure, and the muscles help the body move.
Hydrogen bonds are classified as weak because they are formed fast, but they also break easily under normal biological conditions.
Weak bonds can be easily broken, but this is extremely important because they are in bold in biological systems. For example, they help to decide and stabilize the shapes of water molecules.
<span>The biological term for such organisms is "deuterostomes". Those who's first opening is the mouth are called protostomes.
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