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CAUTION What are homologous chromosomes?
a. chromosomes that are similar in their size, shape, and gene content
b. similar chromosomes that are found in different individuals of the same species
c. the two chromatids in a replicated chromosome
d. any chromosome in a diploid cell
Introduction:
The chromosomes are the thread-like structure that carries the genetic information of an organism. They are made up of nucleic acids and proteins and are found in the nucleus of most of the living cells.
Answer to Problem 1TYK
Correct answer:
Homologous chromosomes are those chromosomes that are similar in shape and size. These chromosomes possess similar gene content and thus, code for the same characteristics.
Explanation of Solution
Explanation/Justification for the correct answer:
Option (a) is given that the chromosomes similar in their size, shape, and gene content are called homologous chromosomes or homologs. The two chromosomes come together and make a homologous pair, which comprises of same genes in the same positions within the chromosomes. It is important to note that these chromosomes are similar and are not considered to be identical.
Hence, Option (a) is correct.
Explanation for incorrect answers:
Option (b) is given that homologous chromosomes are similar chromosomes that are found in different individuals of the same species. The homologous chromosomes are specifically similar to each other in size, shape, and gene content. So, it is a wrong answer.
Option (c) is given that the homologous chromosomes are the two chromatids in a replicated chromosome. The sister chromatid are the identical duplicates, which are produced by the replication of the chromosomes. They are fused together at the same centromere and are homologous chromatids and not the homologous chromosomes. So, it is a wrong answer.
Option (d) is given that any chromosome in a diploid cell are homologous chromosomes. The diploid cell contains autosomes that are homologous to each other, but the sex chromosomes are non-homologous. Therefore, any chromosome in the diploid cell cannot be homologous chromosome. So, it is a wrong answer.
Hence, options (b), (c), and (d) are incorrect.
The chromosomes having the same shape, size, and genetic content are known as homologous chromosomes or homologs. These code for the same characteristics.
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Chapter 13 Solutions
BIOLOGICAL SCIENCE (LL)-W/MOD.MASTERING
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