Cloning Depends on DNA Nucleus Chromosome
{"Image DocumentName": "Cloning Depends on DNA Nucleus Chromosome", "Image ImageDescription": "Each cell contains DNA. DNA is packaged into compact units called chromosomes. Basically a chromosome is one long chain of genetic material. It is the microscopic, rod-shaped, threadlike part of the cell that carries hereditary information in the form of genes. Every cell has chromosomes and all individuals in the same species have the same number of chromosomes. Within an individual, every cell has the same number of chromosomes and generally come in pairs (except in sex cells). People with Down Syndrome have 3 copies of chromosome 21. telomeres, these molecular chains have often been compared to the blank leaders on film and recording tape. Indeed, telomeres seem to perform a similar function in aligning the DNA molecule during the replication process. Protecting the vital DNA molecule from being copied out of synch, these telomeres provide a kind of buffer zone where asynchronous replication errors (that are inevitable) will not result in any of the vital DNA sequences being lost. As a cell gets older, it is under attack by oxides and other so-called free-radical chemicals in the body and environment. We survive as living beings because our cells have the ability to duplicate themselves before being killed by these natural causes. Each time our cells duplicate themselves, a small portion of the DNA molecule is lost and not copied. The loss is usually to the telomere and so the effect is usually insignificant. Scientists recently noted that the length of these telomere chains were shorter as we grew older. Eventually, the telomeres become so shortened that the losses in replication begin to effect the vital DNA molecule sequence and prevent the cell from being able to duplicate itself. This is why we age. Chromosome.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}