Model 1 - Controlled (Selective) Mating: Two Punnett squares depict mating pairs with genotypes Bb and bb, illustrating possible offspring genotypes.

Let’s solve question 3 step by step.

We are told in question 2 that each mating pair has:
- One parent who is heterozygous (Bb)
- One parent who is homozygous recessive (bb)

So, we need to make two Punnett squares — but actually, since all the pairs are the same type of cross (Bb × bb), both Punnett squares will be identical. But maybe the worksheet wants us to show it twice? Or perhaps one for male Bb × female bb and another for male bb × female Bb? Let’s check Model 1.

Looking at Model 1:

In the left box:
- Males are Bb (black beetles)
- Females are bb (white beetles)

In the right box:
- Males are bb (white beetles)
- Females are Bb (black beetles)

So there are two types of crosses:
1. Male Bb × Female bb
2. Male bb × Female Bb

But genetically, these produce the same offspring ratios — because it doesn’t matter which parent contributes which allele; the combination is what matters.

Still, let’s do two Punnett squares as requested — one for each direction — to be thorough.

---

Punnett Square 1: Male Bb × Female bb

Male gametes (sperm): B or b
Female gametes (eggs): b or b

Set up the square:

```
| b | b
---------------------
B | Bb | Bb
---------------------
b | bb | bb
```

Offspring genotypes:
- 2 out of 4 = Bb → heterozygous
- 2 out of 4 = bb → homozygous recessive

So: 50% Bb, 50% bb

---

Punnett Square 2: Male bb × Female Bb

Male gametes: b or b
Female gametes: B or b

Set up the square:

```
| B | b
---------------------
b | Bb | bb
---------------------
b | Bb | bb
```

Offspring genotypes:
- 2 out of 4 = Bb
- 2 out of 4 = bb

Again: 50% Bb, 50% bb

---

So no matter which way you cross them, the possible offspring genotypes are always Bb and bb, each with 50% chance.

Final Answer:
The possible genotypes for offspring from either type of pair are Bb and bb.