Answer:
With millions of different kinds of organisms in the world, scientists must find order in all of this diversity. Scientists group living organisms into one or more of a few major categories as part discipline known as taxonomy. The bodies of organisms are organized into functional systems—cells are organized into tissues, and tissues are organized into organs. Body systems carry out critical functions, such as locomotion, reproduction, digestion, and circulation. All living things on Earth are composed of the same carbon-based, molecular building blocks.

(4) organic catalysts
The job of catalysts in chemical reactions is to make the reaction go faster by lowering the amount of energy needed to activate the reaction. If less energy is needed for the reaction to occur, then the reaction can go faster because a large energy build-up is not needed.
The vinegar is a charged molecule, whereas, the oil is neutral. As like dissolves like, the vinegar can be dissolved with charged molecules and the oil can be dissolved with neutrals. So, to mix vinegar and oil shaking is required.
In case, the person does not mix oil and vinegar dressing before pouring this on the salad, it would not produce a good taste, as the content of vinegar and the oil would not be appropriate.
I think itts virchow
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