Which of the following is not true of organisms kingdom Monera?

Options

A. They originated at least 3.5 billion years ago
B. They have prokaryotic cellular organisation
C. They may be autotrophic or heterotrophic in nature
D. They reproduce by mitosis

Answer

To determine which statement is not true about organisms in the kingdom Monera, we will analyze each option provided in the question step by step.

### Step 1: Evaluate the first option
**Statement:** They originated at least 3.5 billion years ago.
- **Analysis:** This statement is true. Organisms in the kingdom Monera, which includes bacteria, are believed to have originated around 3.5 billion years ago.

### Step 2: Evaluate the second option
**Statement:** They are prokaryotic cell organisms.
- **Analysis:** This statement is also true. The kingdom Monera consists entirely of prokaryotic organisms, which are characterized by the absence of a nucleus and membrane-bound organelles.

### Step 3: Evaluate the third option
**Statement:** They are autotrophic and heterotrophic in nature.
- **Analysis:** This statement is true as well. Monera exhibits a wide range of nutritional modes, including autotrophic (both photoautotrophic and chemoautotrophic) and heterotrophic forms.

### Step 4: Evaluate the fourth option
**Statement:** They reproduce by mitosis.
- **Analysis:** This statement is false. Organisms in the kingdom Monera do not reproduce by mitosis. Instead, they reproduce asexually through methods such as binary fission, fragmentation, or other forms of vegetative propagation. In unfavorable conditions, they may engage in sexual reproduction through conjugation.

### Conclusion
The statement that is not true about organisms in the kingdom Monera is: **They reproduce by mitosis.**

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