Mendel and Darwin are the Fathers of Molecular Biology - Coursework Example

In this experiment, Mendel only used only the color of flowers to study inherence. Mendel attempted a second study using the pea seeds. He wanted to decipher the inheritance of seed shape. He crossed the seeds had smooth coats with wrinkled seeds. The result of this cross was that all plants had smooth seeds. Mendel then self-crossed the smooth-seeded plants. The progeny of these fertilization showed that many plants had smooth seeds and only a few wrinkle-seeded. Mendel tried a third experiment.

In this case, he used pea plants, which differed in two characteristics. The two traits of comparison were color and shape of the seeds. The pure breeds were smooth, yellow seeds and wrinkled green seeds. After the first cross, Gregor observed that, that all the plants were round in shape and yellow in color. When he self-fertilized these offspring, Mendel the plants from this cross were different. The seeds were, round-yellow, wrinkled-yellow, round green, and wrinkled green. This surprised Mendel.

He later concluded that there were ’factors’ responsible for transfer of traits from one generation to another. He went ahead to reveal that the some of the traits did not appear in the first generation. However, the masked traits reappeared in the subsequent generations. Gregor coined his first principle based on the observations of monohybrid crosses. This was the principle of segregation. This principle meant that, there was division of what initially were two factors during the gamete formation process.

Using results from a cross of two contrasting traits, Mendel came up with the principle of Independent Assortment. This principle alludes to independent inheritance of alleles. Although Mendel did not provide the word gene at that time, he proposed that there were factors passed from generation to the other. Figure 1 below is an illustration of the principle of segregation. P represents the parental generation. They are purple and white in color. In the first generation, their offspring are all purple in color.

However, the cross of these individual off springs results to reappearance of white flowered plants. This indicates that the white trait did not get lost. Figure 2 shows laws of independent assortment, the parental traits are round yellow and wrinkled-green. Their offspring demonstrate a variety of characteristics. Nine out of sixteen are round yellow, three are round green, three yellow wrinkled and only one wrinkled green. Figure 1. Illustrates the Principle of segregation Figure 2 indicates the law of independent assortment Charles Darwin is famous for the evolutionary theory.

In his book, ‘The Origin of Species’ he proposes the theory of natural selection. Darwin believed that all organisms evolved from previous ones. The theory holds that, organism develop adaptive mechanism to fit well to their immediate environment. Darwin used breeding experiment to understand variation. In his selective experiments, he noticed that there was accumulation of variation in some organism, which enabled them to survive better to the environment than the ones that did not accumulate variation.

With each successive breeding, Darwin discovered that there was a new group of organism, which had acquired strong characteristic. Darwin concluded that nature caused the accumulation of good traits in organisms that allowed them to fit well to environment. This clearly implies that nature