1. are stored by the body as energy reserves.
lipids
carbohydrates
proteins
nucleic acids

2. structural parts of the body such as skin and hair are made of
lipids
carbohydrates
proteins
nucleic acids

3. are groups of similar cells that do the same sort of work.
tissues
elements
compounds
molecules

1. Lipids are stored by the body as energy reserves.
2. Structural parts of the body such as skin and hair are made of proteins.
3. Tissues are groups of similar cells that do the same sort of work. 

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