A sequential expression of a set of human genes occurs when a steroid molecule binds to the

Options

A. DNA sequence
B. ribosome
C. transfer RNA
D. messenger RNA

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the sequential expression of a set of human genes that occurs when a steroid molecule binds to them. This implies a relationship between steroid hormones and gene expression.

2. **Defining Sequential Expression**: Sequential expression refers to the processes of transcription and translation, which are the steps involved in expressing genes. Transcription is the process where DNA is converted into RNA, and translation is the process where RNA is used to synthesize proteins.

3. **Role of Steroid Molecules**: Steroid molecules, which include hormones, play a crucial role in regulating gene expression. These molecules can bind to specific receptors that then interact with DNA.

4. **Binding to DNA**: When steroid hormones bind to their respective receptors, these hormone-receptor complexes can attach to specific DNA sequences. This binding can either promote or inhibit the transcription of certain genes.

5. **Conclusion**: Therefore, the sequential expression of a set of human genes occurs when a steroid molecule binds to a specific DNA sequence. The correct answer to the question is that the steroid molecule binds to the DNA sequence.

**Final Answer**: The sequential expression of a set of human genes occurs when a steroid molecule binds to the **DNA sequence**.

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