Which is a homologous chromosome pair? chromatid zygote gamete tetrad
The Correct Answer and Explanation is:
Correct Answer: Tetrad
A homologous chromosome pair refers to two chromosomes—one from each parent—that are similar in shape, size, and genetic content. The correct choice from the options provided is tetrad.
During meiosis, specifically in prophase I, homologous chromosomes pair up closely in a process called synapsis. This pairing results in a tetrad, which consists of four chromatids—two from each of the homologous chromosomes. These chromatids are later involved in crossing over, a genetic process that allows the exchange of genetic material and increases genetic diversity in offspring.
To understand why tetrad is the right answer, it helps to look at the incorrect choices:
- Chromatid refers to one of the two identical halves of a duplicated chromosome. A chromatid is not a pair; it is a single strand that becomes visible during cell division.
- Zygote is a single cell formed when a sperm fertilizes an egg. It contains a full set of chromosomes, but it is not a pair of homologous chromosomes.
- Gamete is a reproductive cell (sperm or egg) that contains only one set of chromosomes (haploid). Gametes are produced through meiosis, and they do not have pairs of homologous chromosomes.
In contrast, a tetrad is the structure that includes both homologous chromosomes lined up together, and each chromosome is made of two chromatids. This configuration is essential for genetic recombination and the correct segregation of chromosomes during meiosis.
Therefore, a tetrad directly represents a homologous chromosome pair and is the best answer based on the biological process of meiosis.
