Final answer:
To estimate the number of heterozygous frogs (Aa) with yellow skin spots, one can use Mendel's genetic principles. According to the 1:2:1 genotypic ratio, out of the 350 yellow-spotted frogs, approximately two-thirds should be heterozygous, resulting in about 233 frogs estimated to be Aa.
Step-by-step explanation:
The question pertains to genetics, specifically, the inheritance of dominant and recessive traits in a population of frogs. The dominant trait is yellow skin spots, and out of 500 frogs, there are 350 with this trait. To determine how many frogs are probably heterozygous (Aa), we would use the knowledge from Mendel's principles of inheritance outlined in the question references. When Aa individuals are crossed, we can expect a genotypic ratio of 1:2:1 for AA:Aa:aa. This means that for every 3 offspring showing the dominant phenotype (yellow skin spots), two of them will be Aa (heterozygous), since AA and Aa both display this phenotype.
To calculate this, we assume a ratio of 1 AA : 2 Aa : 1 aa based on the 1:2:1 ratio. Since yellow skin spots are the dominant trait, both AA and Aa individuals will show it, combining for 3 parts of the same phenotype. Given that we have 350 yellow-spotted frogs and 150 non-yellow (assuming all the others do not have spots), we can calculate the likely number of Aa individuals:
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- If the ratio is 1 AA : 2 Aa : 1 aa, then 3 parts out of the total 4 parts (75%) account for frogs with yellow spots.
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- We can estimate that 2 parts out of these 3 parts or (2/3) will be Aa.
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- Therefore, (2/3) of 350 yellow-spotted frogs gives us about 233 frogs that are probably Aa.