Examples of physical changes in properties are melting, transition to a gas, crystallization, etc
double stranded molecule does not describe the structure of RNA. Most RNA are single stranded with partial double stranded regions. RNA has basic component as the DNA that is have four nitrogenous base, contain phosphate group and have 5 carbon sugar.
The theory that a drug attaches itself to specialized cells in the body because of its size, shape, electrical charge, and chemical properties is called receptor site theory.
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