A secondary oocyte has a......... chromosome number while a fertilized ovum has ............ chromosome number.

Explanation

To answer the question, we need to identify the chromosome numbers associated with a secondary oocyte and a fertilized ovum (zygote). Here’s a step-by-step solution:

### Step-by-Step Solution:

1. **Understanding Oogenesis**:
- Oogenesis is the process of egg (ovum) formation in females. It begins with the oogonium, which is diploid (2N).

2. **Formation of Primary Oocyte**:
...