D. do all of these...........
The activation energy as per the definition given by Svante Arrhenius is the minimum amount of energy that is needed for the chemical reaction to proceed. If the amount of the activation energy is decreased then, the reaction would be completed faster.
<span>A.
to fuel their chemical reactions</span>
2. A. Sebaceous glands
Lipids are macromolecules which provide insulation.
<span>A macromolecule is a large molecule. There are four groups of macromolecules: carbohydrates, proteins, nucleic acids and lipids. Lipids consist of glycerol and fatty acids and are constructed from fats, oils, waxes, phospholipids and steroids. A lipid's function is to insulate the body and provide warmth in cold conditions. It can be concluded that a person with very little body fat gets very cold easily and a person with a lot of body fat gets very warm very quickly.
3. B. Thinner
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