Question

Development of the primary oocyte stops its development until sexual maturity of that female.

• A. Metaphase-I
• B. Anaphase-I
• C. Prophase-I
• D. Telophase-I

Hint:

Primary oocytes "pause" in Prophase-I until puberty hits.

Answer 1

The Correct Option is C

Step 1: The setting.
We are looking at how a primary oocyte develops and where its division pauses for a long time.

Step 2: When oogenesis starts.
In a female, the oogonia begin meiosis even before birth. They grow into primary oocytes and enter the first meiotic division.

Step 3: The pause.
The primary oocyte does not finish meiosis-I right away. It stops in the diplotene stage of Prophase-I and stays frozen there for years, all through childhood until puberty.

Step 4: Why the other stages are wrong.
Metaphase-I, Anaphase-I and Telophase-I all come later in meiosis-I. The long arrest happens at the very early Prophase-I stage, so these options do not fit.

Step 5: When it resumes.
Only after sexual maturity, with each menstrual cycle, does one oocyte complete meiosis-I.

Step 6: Conclusion.
Therefore the correct answer is "Prophase-I". \[ \boxed{\text{Prophase-I}} \]