Chromosome

Variations/Selection/ Evolution into the human body. Question 26: Variations in a population is the product of sexual recombination, crossing over during meiosis or by mutation. Sexual recombination is the result of getting different copies of chromosomes between the father and mother during meiosis. Crossing over can produce new combinations of genes that will be expressed in the daughter cells. Mutation can produce random variation in a population that can produce a small or big change in a…

part of the Mitosis. In Prophase, the chromosomes will coil up and the nucleus and nucleolus will disappear. The next phase of Mitosis is Metaphase, in metaphase the newly-created chromosomes will line up along the metaphase plate or the equator of the cell. The phase of Mitosis following Metaphase is Anaphase. In Anaphase those perfectly aligned chromosomes created in Metaphase, will now split. The final phase of Mitosis is Telophase. In telophase the chromosomes will uncoil and the nuclear…

Down syndrome Down syndrome is one of the many disorders that affect hundreds of thousands of people around the world. Down syndrome, also known as Trisomy 21, occurs when an extra copy of the 21 chromosome is made. The disorder usually causes several impairments that can range from mild to severe; impairments include both mental and physical aspects of the individual. Presently, there is no full cure for Down syndrome, but there are numerous of treatments options and way to enhance the…

of one or more modifier genes, for example the genetic background, the example of this is the complete baldness gene to the brown hair gene. Sex-linkage Sex linkage is the phenotypic manifestation of an allele which is connected to the sex chromosome of an individual, examples of this include the genes that control colour blindness and the male pattern baldness Sex-influenced effects Sex influenced effects are traits that are influenced by sex, for example if a male has one recessive…

syndrome, is a severe pleiotropic autosomal recessive developmental disorder caused by dysfunction of primary cilia during early embryogenesis. In addition, it has discovered that there is more than one gene can cause the disease and which genes on chromosome 8, 11 and 17. And it is a rare disease and the different incidence of this disease around the world at a rate of 1 to 1…

states that during the formation of gamete the two allele pairs separate randomly. The second law is independent assortment which states during gamete formation each pair of the allele will segregate independently of the rest of the pairs of the chromosomes. The third law is the law of dominance which is that alleles can be dominant or recessive with the expression of the dominant trait when a minimum of one dominant allele is present. Mendel described inheritance as the passing of genetic…

Bongani Magadla Fallen Angel Sylas looked down at the blemishes that were beginning to blossom on his hands. His caramel complexion slowly becoming darker and lighter at the same time. The usual nightmares had not visited him last night; blessing him with restful sleep for the first time in almost a month. The faces in those nightmares were as clear as day. He pressed his hand down to the Stabilizer. After doing this for 16 years, the sting of the Stabilizer was little more than an ant bite.…

still ongoing. The frequency of a child with progeria is one in four million newborns. 200-250 children in the world are living with progeria. The disease affects both male and female and all races. The inheritance of progeria is not on a sex chromosome and its dominant which means one copy of the gene in each cell is sufficient to cause progeria. Almost always occurs in people with no history of the disorder. The gene change is almost always a chance but is extremely rare. Chances with a…

causes lymphedema of the legs and recurrent cholestasis in infancy. This also causes slow progress to hepatic cirrhosis and giant cell hepatitis with fibrosis of the portal tracks. The genetic cause is unknown, but it is inherited in some way in the chromosomes that it is located in. People who have this suffer severe neonatal cholestasis, but this usually lessons during child hood. After the childhood stage it usually becomes episodic, and they also develop chronic severe lymphedema. The cause…

can get this terrible disease. Other names for this disorder are RTS, RTT, Cerebral Atrophic Hyperammonemia, Autism-dementia-ataxia-loss of purposeful hand use syndrome, and etc. Rett Syndrome is caused by a mutation in a particular gene in the X chromosome. And then that gene gets other genes to get involved into the development. The parents do not pass this disease down but rather the mutation happens in the own girls body. But the mutation that causes this disease occurs randomly. But…