Concept explainers
a.
To determine: The possible
Introduction: The human blood group is an example of codominance where the alleles for the two antigens A and B are equally dominant. It means that when the two antigens A and B are present, the blood group is AB whereas in the absence of both the antigens, the blood group is O.
b.
To determine: The genotype of the individuals with blood group O.
Introduction: The individuals with the blood group O lack the surface antigens for both the blood groups A and B. Therefore, the expression of type O blood group occurs when the individual inherits both the recessive alleles. It makes people with type O blood group to become universal donors.
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Human Heredity: Principles and Issues (MindTap Course List)
- Mendel performs a cross using a true-breeding pea plant with round, yellow seeds and a true- breeding pea plant with green, wrinkled seeds. What is the probability that offspring will have green, round seeds? Calculate the probability for the F1 and F2 generations.arrow_forwardMendel's concept of dominance states that in a genotype where two different alleles of a locus are present, only the trait encoded by the dominant allele is observed. Give a molecular explanation for dominance, i.e. explain intracellular molecular events that can result in what we observe as dominance on a phenotypic level. Use the gene that encodes seed shape in peas as an example, where roun(R) is dominant over wrinkled(r), to explain how RR and Rr plants can have the same phenotype.arrow_forward. Considering the yellow and green pea color phenotypes studied by Gregor Mendel:a. What is the biochemical function of the proteinthat is specified by the gene responsible for thepea color phenotype?b. A null allele of a gene is an allele that does notspecify any of the biochemical function that thegene normally provides. Of the two alleles Y and y,which is more likely to be a null allele?c. In terms of the underlying biochemistry, why is theY allele dominant to the y allele?d. Why are peas that are yy homozygotes green?e. The amount of the protein specified by a gene isroughly proportional to the number of functionalcopies of the gene carried by a cell or individual.What do the phenotypes of YY homozygotes, Yyheterozygotes, and yy homozygotes tell us aboutthe amount of the Sgr enzyme (the product of thepea color gene) needed to produce a yellow color?arrow_forward
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