Living organisms are grouped into eukaryotes and prokaryotes on the basis of

Options

A. ribosomes
B. nucleus
C. plasma membrane
D. chloroplast

Answer

**Step-by-Step Solution:**

1. **Understanding the Classification**: Living organisms are classified into two main groups: eukaryotes and prokaryotes. This classification is based on certain structural and functional characteristics.

2. **Defining Prokaryotes**: Prokaryotes are unicellular organisms that lack a well-defined nucleus. Their genetic material is not enclosed within a membrane. Examples include bacteria and archaea.

3. **Defining Eukaryotes**: Eukaryotes are organisms whose cells contain a well-defined nucleus enclosed by a nuclear membrane. They also have other membrane-bound organelles. Examples include plants, animals, fungi, and protists.

4. **Key Differences**: The primary basis for the classification into eukaryotes and prokaryotes is the presence or absence of a nucleus. Eukaryotes have a true nucleus, while prokaryotes do not.

5. **Other Factors**: While the nucleus is a significant factor, other characteristics such as the presence of ribosomes, plasma membrane structure, and organelles like chloroplasts can also be considered. However, the defining feature remains the nucleus.

6. **Conclusion**: Therefore, living organisms are grouped into eukaryotes and prokaryotes primarily based on the presence or absence of a well-defined nucleus.

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