Gregor Mendel

A person's phenotype is brought about by an interaction between their genetic makeup and their environment. gamete production, and the emergence of iodin trait leading not affect the emergence of some other trait. However, some genes are linked together on the said(prenominal) chromosome and do not sort independently.

Mendel explored dominant and recessive alleles victimisation monohybrid and dihybrid crosses (Wilson, 2000, 140-141). For instance, if a dominant allele A gives green peas, and a recessive allele a gives yellowish peas, a countersink homozygous for the dominant gene for green peas will behave the AA genotype, and a plant homozygous for the recessive gene for yellow peas will have the aa genotype. Heterozygous plants will have the genotype Aa and will have green peas. In a monohybrid cross, the parents will have the phenotypes AA and aa. In the F1 generation ( youth), all the plants will be heterozygotes with the Aa genotype and have green peas. In the second generation, which combines deuce heterozygotes with each other, there is unmatched risk in quaternity of a homozygous dominant way out (AA), cardinal chance in four of a homozygous recessive offspring (aa), and one chance in dickens of a heterozygous offspring (Aa). Since the dominant gene, A, codes for green peas, three quarters of the offspring will produce green peas, and one quarter will produce yellow peas. This is Mendelian genetics.

In a dihybrid cross, two traits are followed at once, such as

If there is non-disjunction of homologous chromosomes, then one young woman cell gets two copies of the chromosome and one gets none. If this occurs, as mentioned above, genetic disorders occur. In Downs syndrome, which is caused by trisomy 21, the individual has three copies of chromosome 21 (Genetic cognition accomplishment amount of money, 2003). This means that when either the egg or the sperm was undergoing meiosis, chromosome 21 did not separate between the two daughter cells, and one cell received both copies of the chromosome.

This gamete was then fertilized by a normal sperm or egg bearing one chromosome 21, resulting in the offspring having three copies of chromosome 21, known as trisomy 21, and resulting in Down's syndrome.

Gregor Mendel and Mendelian Genetics. (2004). Retrieved at:

Genetic Science Learning Center (2003). Making a Karyotype.

A karyotype is an individual's chromosome profile and is produced by placement pictures of the chromosomes in order of size from the largest to the smallest, using their banding radiation diagram and centromere position as a guide (Genetic Science Learning Center, 2003). The most important way to separate chromosomes is by size. Next, when the chromosomes are stained using a Giemsa stain, bands appear, and the size and kettle of fish of these bands is characteristic for each pair of chromosomes. The position of the centromere congress to the end of the chromosome is another guide used to separate pairs of chromosomes for identification purposes. The centromere is either metacentric ( darling the middle), submetacentric (the centromere is off center, fashioning one arm longer than the other), or acrocentric (very near the end of the chromosome). If the arms are of different length because of a submetacentric centromere, then the chromosomes are aligned with the short arm (p) top(prenominal) (the long arm is designated q).

Order your essay at Orderessay and get a 100% original and high-quality custom paper within the required time frame.