When small unit combine to form a large single unit then it is called

Options

A. Polymer
B. Nylon
C. Cellulose
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the term used when small units combine to form a larger single unit.

2. **Identifying the Small Units**: The small units referred to in the question are known as "monomers." Monomers are the basic building blocks of larger structures.

3. **Combining Monomers**: When many monomers join together through chemical bonds, they form a larger structure. This process involves the formation of covalent bonds between the monomers.

4. **Defining the Large Unit**: The large unit formed by the combination of monomers is called a "polymer." Polymers can be natural or synthetic.

5. **Examples of Polymers**: Two common examples of polymers are:
- **Nylon**: A synthetic polymer known as a polyamide, which is made through the combination of monomers with amide linkages.
- **Cellulose**: A natural polymer found in plants, made up of glucose monomers.

6. **Conclusion**: Therefore, the answer to the question is that when small units combine to form a large single unit, it is called a "polymer."

**Final Answer**: The large unit formed when small units combine is called a polymer.

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