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It is the simplest unit of a chemical substance. It usually consists of a group of two or more atoms. It is the smallest unit into which a substance can be divided without chemical change.

• MOLECULE
• PARTHENOGENESIS
• CELL CLONING
• ORGANISM CLONING
• MOLECULAR CLONING
• NATURAl CLONING
• CLONING
• A CELL
• SOMATIC-CELL NUCLEAR TRANSFER
• DEOXYRIBONUCLEIC ACID