The genes which upon activation produce malignant neoplasms are called

Options

A. Pleiotropic genes
B. Multiple genes
C. Proto - Oncogenes
D. Neonatal genes

Answer

To answer the question "The genes which upon activation produce malignant neoplasms are called," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Malignant Neoplasms**:
- Malignant neoplasms refer to cancerous tumors that grow uncontrollably and can invade surrounding tissues. This uncontrolled growth is a hallmark of cancer.

2. **Role of Genes in Cell Growth**:
- Genes play a crucial role in regulating cell growth and division. Certain genes are responsible for promoting normal cell growth, while others can lead to uncontrolled growth when mutated or activated improperly.

3. **Identifying the Relevant Genes**:
- There are specific types of genes that, when activated, can lead to the development of cancer. These include proto-oncogenes, which are normal genes that can become oncogenes (cancer-causing genes) when mutated or overexpressed.

4. **Understanding Proto-oncogenes**:
- Proto-oncogenes are genes that, when activated by various factors such as carcinogens, can lead to malignant neoplasms. They are involved in signaling pathways that promote cell division and growth.

5. **Conclusion**:
- Based on the understanding that the activation of certain genes leads to cancerous growth, the correct answer to the question is "Proto-oncogenes."

### Final Answer:
The genes which upon activation produce malignant neoplasms are called **Proto-oncogenes**.

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