Question

In guinea pigs, short hair, S, is dominant to long hair, s.

Two heterozygous short hair guinea pigs mate. Write the genotype ratio

Answer 1

When two heterozygous short hair guinea pigs (genotype \(Ss\)) mate, we can use a Punnett square to determine the genotype ratio of their offspring.

The possible gametes from each parent are:

- One parent can produce \(S\) or \(s\)
- The other parent can also produce \(S\) or \(s\)

Setting up the Punnett square:

```
S s
----------------
S | SS | Ss |
----------------
s | Ss | ss |
----------------
```

From the Punnett square, we can see the offspring genotypes:

- \(SS\): 1
- \(Ss\): 2
- \(ss\): 1

So the genotype ratio of the offspring is:

- \(1 SS : 2 Ss : 1 ss\)

In summary, the ratio is \(1:2:1\).