In genetic males, there is one pair that is not homologous. Identify the pair and explain why.
Describe the processes of sexual reproduction and asexual reproduction through parthenogenesis.
4 years ago
Answered By Alisha E
For the first part of the question, the pair that is not homologous is the pair with the sex chromosomes because in males they have an X chromosome and a Y chromosome and so since these are not identical they are not homologous (females have XX so they are homologous).
For the second part, in parthenogenesis females gametes (eggs) and rarely male gametes develop without fertilization. The egg can be haploid or diploid and the species that undergo parthenogenesis can either be obligate (only reproduce with parthenogenesis) or facultative (can switch between sexual reproduction and parthenogenesis). Since offspring develop from gametes that are not fertilized, it is considered incomplete sexual reproduction (though some people consider it asexual reproduction). In haploid parthenogenesis a haploid egg develops into a haploid offspring, however this is rare. In diploid parthenogenesis there are two pathways. Automixis is when the chromosomes of the haploid cell are duplicated, or when it joins with another haploid cell. Apomixis is when two identical diploid egg cells (produced through mitosis and not meiosis) develop into diploid offspring. Since parthogenesis in itself is considered neither sexual nor asexual reproduction, it is possible that when the question asks for sexual reproduction through parthogenesis it is referring to automisis and when it asks for asexual reproduction through parthogenesis it is referring to haploid parthogenesis and apomixis.
4 years ago
Answered By Alisha E
For the first part of the question, the pair that is not homologous is the pair with the sex chromosomes because in males they have an X chromosome and a Y chromosome and so since these are not identical they are not homologous (females have XX so they are homologous).
For the second part, in parthenogenesis females gametes (eggs) and rarely male gametes develop without fertilization. The egg can be haploid or diploid and the species that undergo parthenogenesis can either be obligate (only reproduce with parthenogenesis) or facultative (can switch between sexual reproduction and parthenogenesis). Since offspring develop from gametes that are not fertilized, it is considered incomplete sexual reproduction (though some people consider it asexual reproduction). In haploid parthenogenesis a haploid egg develops into a haploid offspring, however this is rare. In diploid parthenogenesis there are two pathways. Automixis is when the chromosomes of the haploid cell are duplicated, or when it joins with another haploid cell. Apomixis is when two identical diploid egg cells (produced through mitosis and not meiosis) develop into diploid offspring. Since parthogenesis in itself is considered neither sexual nor asexual reproduction, it is possible that when the question asks for sexual reproduction through parthogenesis it is referring to automisis and when it asks for asexual reproduction through parthogenesis it is referring to haploid parthogenesis and apomixis.