Cell division

Background: What is Down Syndrome? Down Syndrome is a chromosomal disorder caused by an error in cell division that results in an extra twenty-first chromosome, that causes birth defects of developmental and intellectual delays. The human body is composed of trillions of cells and within the nucleus of each cell are structures called chromosomes (Parks, 2009). About eight million babies are diagnosed with Down Syndrome in the United States with approximately twenty thousand in Western Europe…

deliver the DNA, were developed including viruses, plasmids, and minicircle DNA. These vectors are engineered to contain the therapeutic genes. Viral vectors hold the advantage of a higher transfection profile as well as the ability to target certain cells. However, viral vectors are limited by the amount of genes they can carry, in vivo immune response, and safety concerns. Most gene therapy cases have employed viral vectors despite their drawbacks. On the other hand, plasmids can carry larger…

Trisomy is a cell that has three copies of one chromosome instead of having the normal two copies. Trisomy 21 is the congenital disorder better known as Down syndrome. This occurs when each cell has three copies of chromosome twenty-one rather than having a normal pair. Nondisjunction is "an error in which homologous chromosomes or sister chromatids fail to separate normally during meiosis or mitosis" (Huether, McCancep, 2012, p.42). Therefore, a common cause of Down syndrome is nondisjunction…

research to see how the growth of cells could lead to cell division. What this team did first was they chose to test on yeast because it is easy to manipulate and they believed that if they could have success on yeast, they could take what they found and use it on human cells. The team began to look at a protein called Cln3, which is the first protein that leads up to the G1/S transition because they thought that the first cell would show them something on why cells divide. What happen was the…

Nucleus The Nucleus is an example of a command centre found inside a eukaryotic cell; it’s usually the most prominent organelle, yet it occupies only 10% of the total volume of the cell. If this cell did not have a Nucleus, it would be defined as a prokaryote cell, however if the Nucleus was damaged and not repaired, the cell would simply die. The cell nucleus is enclosed within a double membrane (contains an Inner and Outer Nuclear Membrane) called the Nuclear Envelope, which separates the…

A new and highly talked about topic is stem cell research. Stem cell research is an extraordinary, yet very controversial subject. Stem cells are a very large focus in today’s study of biomedical research. Stem cell research is beneficial because the research that is done can help cure diseases and regenerate cells that will be able to give humans, and their body’s, another chance at being healthy. Stem cells are defined as, “Undifferentiated cells of a multicellular organism that are…

chromosomal abnormality (Dictionary, 2016). Down’s syndrome is caused by an extra chromosome 21 in the genome in an individual. The extra chromosome causes moderate intellectual disability. The extra chromosome can also result in an error in cell division. The error is usually prior to fertilization but for some reason nobody understands what causes theses errors. People with Down’s syndrome have 50% more genetic material on the 21st chromosome than people who do not have Down’s syndrome…

usually caused by an error in cell division, called “nondisjunction.” Nondisjunction results in an embryo with not two but three copies of chromosome 21. As the embryo develops, the extra chromosome is duplicated in every cell of the baby's body. Mosaicism is the least common form of down syndrome and only accounts for 1% of cases of down syndrome. Mosaicism is diagnosed when there is a mixture of two types of cells, some with the usual 46 chromosomes and some with 47. The cells with 47…

Even though systematics previously used more conventional systems such as Chatton’s division of life in to two main cellular groups; the eukaryote-prokaryote dichonomy (cited in Sapp, 2005), as well as Whittaker’s Five Kingdom system to organise all living things (Whittaker, 1969), they do not co-exist compatibly or correctly. The five kingdom system is not phylogenetically correct and eukaryote and prokaryote systems do not take into consideration new sequencing abilities (Kandler, Wheelis &…

pathway is a chain of proteins in the cell that relays an extracellular signal from the Ras protein to the DNA in the nucleus of the cell. This pathway consists of multiple phosphorylations as MAPKKK phosphorylates and activates MAPKK which then phosphorylates and activates MAPK. At the end of this cascade, MAPK phosphorylates various effector proteins (Alberts, 557). This signaling pathway plays an important role in cells as it results in complex changes in cell decisions and behaviors such…