Sexual Reproduction

Sexual reproduction is a biological process by which organisms create descendants. It involves the fertilization of one sex cell “gamete” by another, producing a new cell called “a zygote,” which develops into a new organism. Sexual reproduction occurs in many one-celled organisms and in all multicellular plants and animals. In higher invertebrates and in all vertebrates it is the exclusive form of reproduction. Sexual reproduction is of great significance in that, because of the fusion of two separate parental nuclei, the offspring inherits endlessly varied combinations of characteristics that will ensure its survival. This probably explains the predominance of sexual reproduction among higher forms. Sexual reproduction is essentially cellular in nature. The fusion of two cells occurs in sexual reproduction. Sexual reproduction begins with production of sex cells via meiosis, a process that halves the genetic material of each parent in preparation for combination with another sex cell. The specialized cells that are required for sexual reproduction are known as gametes. A type of cell division called meiosis produces gametes.

One of the most important components of sexual reproduction is Chromosomes. Chromosomes are organized structures of DNA and protein found in cells. A chromosome is made of up single piece of coiled DNA, which contains many genes, regulatory elements and other nucleotides sequences. Chromosomes also consist of DNA-bound proteins that package DNA and control its functions. A condensed structure known as chromatin can be found in eukaryote organisms, which is the packaged nuclear chromosome. This makes it possible for DNA, which is very long to fit into the nucleus of cells. Chromosomes are essential for cellular division and must be replicated, divided and successfully be able to pass on their daughter cells to ensure genetic diversity and survival. A Human body requires 46 chromosomes; these results from 23 pairs gained from each parent....