Answer :
- First cross (Ww x ww) yields 50% heterozygous offspring.
- Second cross (Ww x WW) yields 0% homozygous recessive offspring.
- The probability of heterozygous offspring in the first cross is $\boxed{50\%}$.
- The probability of homozygous recessive offspring in the second cross is $\boxed{0\%}$.
### Explanation
1. Problem Analysis
We are given two separate genetic crosses and asked to determine the probabilities of specific offspring genotypes for each. The first cross involves a heterozygous male (Ww) and a homozygous recessive female (ww). The second cross involves a heterozygous individual (Ww) and a homozygous dominant individual (WW).
2. First Cross: Probability of Heterozygous Offspring
For the first cross (Ww x ww), we can use the Punnett square to determine the possible offspring genotypes. The Punnett square shows that there are two possible genotypes: Ww and ww. Two out of the four offspring are Ww (heterozygous). Therefore, the probability of heterozygous offspring is $\frac{2}{4} = \frac{1}{2} = 50\%$.
3. Second Cross: Probability of Homozygous Recessive Offspring
For the second cross (Ww x WW), we again use the Punnett square to determine the possible offspring genotypes. The Punnett square shows that there are two possible genotypes: WW and Ww. None of the offspring are ww (homozygous recessive). Therefore, the probability of homozygous recessive offspring is $\frac{0}{4} = 0\%$.
4. Final Answer
Therefore, the probability of heterozygous offspring in the first cross is 50%, and the probability of homozygous recessive offspring in the second cross is 0%.
### Examples
Understanding genetic probabilities is crucial in breeding programs, whether for agriculture or pets. For example, a farmer might want to know the likelihood of certain traits appearing in their crops, or a breeder might want to predict the coat color of kittens. These probabilities help make informed decisions about which individuals to breed to achieve desired outcomes.
- Second cross (Ww x WW) yields 0% homozygous recessive offspring.
- The probability of heterozygous offspring in the first cross is $\boxed{50\%}$.
- The probability of homozygous recessive offspring in the second cross is $\boxed{0\%}$.
### Explanation
1. Problem Analysis
We are given two separate genetic crosses and asked to determine the probabilities of specific offspring genotypes for each. The first cross involves a heterozygous male (Ww) and a homozygous recessive female (ww). The second cross involves a heterozygous individual (Ww) and a homozygous dominant individual (WW).
2. First Cross: Probability of Heterozygous Offspring
For the first cross (Ww x ww), we can use the Punnett square to determine the possible offspring genotypes. The Punnett square shows that there are two possible genotypes: Ww and ww. Two out of the four offspring are Ww (heterozygous). Therefore, the probability of heterozygous offspring is $\frac{2}{4} = \frac{1}{2} = 50\%$.
3. Second Cross: Probability of Homozygous Recessive Offspring
For the second cross (Ww x WW), we again use the Punnett square to determine the possible offspring genotypes. The Punnett square shows that there are two possible genotypes: WW and Ww. None of the offspring are ww (homozygous recessive). Therefore, the probability of homozygous recessive offspring is $\frac{0}{4} = 0\%$.
4. Final Answer
Therefore, the probability of heterozygous offspring in the first cross is 50%, and the probability of homozygous recessive offspring in the second cross is 0%.
### Examples
Understanding genetic probabilities is crucial in breeding programs, whether for agriculture or pets. For example, a farmer might want to know the likelihood of certain traits appearing in their crops, or a breeder might want to predict the coat color of kittens. These probabilities help make informed decisions about which individuals to breed to achieve desired outcomes.