Starches are
A neither polymers nor monomers
B polymers
C both polymers and monomers
D monomers
The correct answer and explanation is:
The correct answer is B. Polymers.
Starches are classified as polymers because they are made up of repeating subunits called glucose molecules, which are linked together through glycosidic bonds. These glucose units, which are simple sugars, bond in long chains to form starches, making them a type of complex carbohydrate. There are two main types of starch: amylose and amylopectin. Amylose consists of long, unbranched chains of glucose, while amylopectin is branched. Both types are considered polysaccharides, meaning they are composed of many monosaccharides (single sugar units) joined together.
A polymer is defined as a large molecule made up of repeating smaller units called monomers. In the case of starch, the monomers are glucose molecules. These monomers are connected by covalent bonds in a repeating pattern, forming long chains. This structure gives starch its characteristic properties, such as its ability to store energy in plants and its digestibility by humans and other animals.
Monomers, on the other hand, are the basic building blocks of polymers. In starch, glucose is the monomer. When starch is broken down during digestion, the glucose monomers are released and can be used by the body for energy.
Thus, starch is a polymer because it is made of repeated glucose monomers. It is not a monomer itself because it is a complex structure consisting of many sugar units linked together.