At puberty, a female has more than 400,000 immature egg cells in her ovaries. Calculate the percentage of these eggs that will ovulate, assuming that 13 ovarian cycles occurs per year in her reproductive life span of 40 years.

Options

A. `52%`
B. `0.13%`
C. `5.2`
D. `13%`

Answer

To solve the problem, we need to calculate the percentage of immature egg cells (oocytes) that will ovulate during a female's reproductive lifespan. Here’s a step-by-step breakdown of the solution:

### Step 1: Determine the Total Number of Ovarian Cycles
A female has 13 ovarian cycles per year. If we consider a reproductive lifespan of 40 years, we can calculate the total number of ovarian cycles as follows:

\[ \text{Total Ovarian Cycles} = \text{Cycles per Year} \times \text{Years} \]

\[ \text{Total Ovarian Cycles} = 13 \text{ cycles/year} \times 40 \text{ years} = 520 \text{ cycles} \]

### Step 2: Identify the Total Number of Immature Egg Cells
At puberty, a female has approximately 400,000 immature egg cells in her ovaries.

### Step 3: Calculate the Percentage of Eggs that Ovulate
To find the percentage of eggs that will ovulate, we use the formula:

\[ \text{Percentage of Eggs that Ovulate} = \left( \frac{\text{Total Ovarian Cycles}}{\text{Total Egg Cells}} \right) \times 100 \]

Substituting the values we have:

\[ \text{Percentage of Eggs that Ovulate} = \left( \frac{520}{400,000} \right) \times 100 \]

### Step 4: Perform the Calculation
Now, we can perform the calculation:

\[ \text{Percentage of Eggs that Ovulate} = \left( \frac{520}{400,000} \right) \times 100 = 0.13\% \]

### Conclusion
Thus, the percentage of immature egg cells that will ovulate is **0.13%**.

### Final Answer
The correct answer is **0.13%**.

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