If both parents are heterozygous what is the probability that both parents will contribute a recessive allele for any given trait?
Please name three characteristics of incomplete dominance in humans.
I have Hair, curly and straight hair both make wavy hair. Is there any others that might be useful?
Thank you for taking time in answering these questions
Please name three characteristics of incomplete dominance in humans.
I have Hair, curly and straight hair both make wavy hair. Is there any others that might be useful?
Thank you for taking time in answering these questions
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The answer is correct that two heterozygous parents have a 25% chance of both of them transmitting their recessive alleles to an offspring. This can be shown by a simple Punnett square. Let's say that each parent has brown eyes(B) but carries a blue-eyed gene (b). Cross Bb with Bb, and you will see that 25% of their offspring have BB alleles, 50% have Bb alleles, and 25% have bb alleles.
Incomplete dominance means that there can be more than one gene expressed for the dominant trait. A good example in human beings is blood type. Type A and type B genes are codominant, while type O genes are recessive.
If one parent donates a type A gene and the other a type B gene, the genotype of the offspring will be AB, and the phenotype is type AB blood, where both A and B proteins are found on the red blood cells of the offspring. Neither A nor B genes can dominate the other, but both dominate type O genes.
Eye color in human beings, in spite of my simple Punnett square example, is actually more complex and also involves multiple alleles with incomplete dominance, which is why we have more than two types of eye colors and among them, there can be dark or light differences. For example, some people with brown eyes have very dark brown eyes and others have lighter brown eyes. There is hazel, which is lighter still but is NOT the same as green eyes. Green eyes can vary from quite greenish to nearly blue-green, and blue-eyed people can have very pale blue eyes, medium blue to dark blue eyes because of the incomplete dominance of multiple alleles. I hope this helped?
Incomplete dominance means that there can be more than one gene expressed for the dominant trait. A good example in human beings is blood type. Type A and type B genes are codominant, while type O genes are recessive.
If one parent donates a type A gene and the other a type B gene, the genotype of the offspring will be AB, and the phenotype is type AB blood, where both A and B proteins are found on the red blood cells of the offspring. Neither A nor B genes can dominate the other, but both dominate type O genes.
Eye color in human beings, in spite of my simple Punnett square example, is actually more complex and also involves multiple alleles with incomplete dominance, which is why we have more than two types of eye colors and among them, there can be dark or light differences. For example, some people with brown eyes have very dark brown eyes and others have lighter brown eyes. There is hazel, which is lighter still but is NOT the same as green eyes. Green eyes can vary from quite greenish to nearly blue-green, and blue-eyed people can have very pale blue eyes, medium blue to dark blue eyes because of the incomplete dominance of multiple alleles. I hope this helped?