Which of the following statements about the SRY gene is FALSE

Which of the following statements about the SRY gene is FALSE? Group of answer choices Two copies of this gene are required to trigger the female sex developmental pathway. When functional, it triggers male sex determination. It triggers testes development. It is located on the Y chromosome. Without it, the female sex developmental pathway is initiated.

The correct answer and explanation is:

Correct Answer:
Two copies of this gene are required to trigger the female sex developmental pathway. (This statement is FALSE.)

✅ Explanation (300 words):

The SRY gene (Sex-determining Region Y) is a critical gene located on the Y chromosome that initiates male sex development in mammals, including humans. It plays a pivotal role in determining male biological sex by activating the development of testes from undifferentiated gonadal tissue.

🔬 Function of the SRY Gene:

• The SRY gene encodes a transcription factor that turns on a cascade of genes involved in the development of testes.
• Once the testes form, they produce testosterone and other hormones that direct the development of male internal and external genitalia.

❌ Why the Statement is FALSE:

“Two copies of this gene are required to trigger the female sex developmental pathway.”

This is false for several reasons:

1. The SRY gene is not involved in female development.
   • In fact, SRY suppresses the female developmental pathway. It triggers male sex determination, not female.
2. Females typically do not have the SRY gene.
   • They have two X chromosomes (XX), neither of which normally carries the SRY gene.
3. Only one copy of the SRY gene is needed to initiate male development.
   • A single functional copy on the Y chromosome is sufficient to start the male pathway.
4. If the SRY gene is missing or nonfunctional, even if a Y chromosome is present, the default pathway (female) proceeds.

✅ All Other Statements Are TRUE:

• ✅ “When functional, it triggers male sex determination.” ✔️
• ✅ “It triggers testes development.” ✔️
• ✅ “It is located on the Y chromosome.” ✔️
• ✅ “Without it, the female sex developmental pathway is initiated.” ✔️

Conclusion: The false statement is that “two copies of this gene are required to trigger the female sex developmental pathway.” In reality, no SRY gene leads to female development, not the presence of two copies.