Model 1 - Controlled (Selective) Mating showing mating pairs with genotypes Bb and bb.

Let’s look at Model 1 – Controlled (Selective) Mating.

We see two big boxes, each divided into smaller sections. Each section shows one male and one female beetle paired together — that’s one mating pair.

In the left box:
- There are 3 rows.
- Each row has 2 pairs (one on the left side of the vertical line, one on the right).
→ So 3 rows × 2 pairs = 6 pairs in the left box.

In the right box:
- Also 3 rows.
- Each row has 2 pairs.
→ So 3 rows × 2 pairs = 6 pairs in the right box.

Total mating pairs = 6 (left) + 6 (right) = 12 pairs.

Final Answer:
12