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A heterozygous individual has _______ for a trait being studied.
| a. the same allele on both homologous chromosomes |
| b. two different alleles of a gene |
| c. a haploid condition, in genetic terms |
Introduction:
Individuals in the population carry a specific set of alleles, known as genotype. The examples of genotype are homozygous and heterozygous. The phenotype of a plant depends on its genotype, and it is the trait of the individual that can be observed.
Answer to Problem 1SA
Correct answer:
Two different alleles of a gene are carried by a heterozygous individual for a trait being studied. Hence, the correct answer is option b.
Explanation of Solution
Reason for correct answer:
Option b. is given as “two different alleles of a gene.”
Locus represents the “location of a gene” on a chromosome. Individuals carry two copies of a gene because their cells are diploid and pairs of the chromosome are present in these cells. These double copies of any gene can be similar, or they can vary as alleles. If an individual carries two different alleles at a particular locus then its genotype would be called heterozygous.
Reason for incorrect answer:
Option a. is given as, “the same allele on both homologous chromosomes.”
If an individual has the same allele on both homologous chromosomes then the individual would be known as homozygous. Hence, option a. is incorrect.
Option c. is given as, “a haploid condition, in genetic terms.”
In individuals there are always two copies of genes are present. So, a heterozygous individual is a diploid condition, not a haploid condition. Hence, option c. is incorrect.
Hence, the options a. and c. are incorrect.
Therefore, the alleles of a gene on both homologous chromosomes would be different in a heterozygous individual. Thus, the correct option is b.
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Chapter 13 Solutions
BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)
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