origin of life
The theme brought in chapter one is the origin of life. Life is seen as a tricky thing that consists of two different skills that are the ability to replicate and the ability to create order. The ability to reproduce is made possible by the existence of a recipe which is the information needed to create a new body. Scientists found some chromosomes, and it is believed that they contain some code-script where the entire pattern of the individual’s future development and its functioning are held. Life, to a rough approximation, consists of the chemistry of three atoms, hydrogen, carbon and oxygen, which between them make up ninety-eight per cent of all atoms in living beings. Recipes are stored in DNA, and these recipes are translated into proteins, and these proteins enable DNA to replicate. RNA being a chemical substance links both DNA and protein. RNA is used mainly in the translation of the message from
The alphabet of DN A to the alphabet of proteins. Therefore the ancestor of life are the bacteria that existed before other living things, and it’s believed that they were able to multiply and produce offspring’ hence the origin of life.
The central theme brought in chapter two is the evolution of human beings from ancient apes. The scientists, through a natural selection, found that human beings gorillas and chimpanzees came from the same ancestors that existed in Africa. Human being and the chimpanzees were found to be having 78% likeness. Several factors supported the above statement, which includes the number of chromosomes in them. Human beings were said to be possessing 24 pairs of the chromosome as in the other animals. This statement was later refuted as a human was found to be having one pair of chromosomes less a situation which was caused by the 2pairs of the ape chromosomes fused in them to form one pair. It is believed that the ancient split was caused by some stretches of DNA hence the chimpanzees’ genome and that of human beings sowed little difference proving the same origin. The differences between human beings and the chimpanzee are their airy body, different shape of heads, variation in body shapes, the difference in walking limbs, makes unusual noises. Some of the similarities include thirty-two teeth, five fingers, two eyes and a liver. Both needs hair, dry skin, a spinal column among others sowing their likeness. In this chapter, man is also viewed to achieve ecological success as they have colonized the habitats of all other animals.
In the third chapter, a brief history of genetic inheritance is given. Garrod describes a gene as a recipe for a single chemical. He conducted a thorough examination of his patients, who were first cousins and second cousins. The investigation made him introduced the hypothesis on “inborn errors of metabolism” that reached an assumption that genes were there to produce chemical catalysts. He wrote that inborn errors of metabolism are due to failure of a step in the metabolic sequence due to loss or malfunctions of an enzyme. Today the primary function of a gene is to store the recipe making the protein. It is the protein that is left with every chemical, structural and regulatory happenings in the body like the generation of energy, food digestion, among others. In an attempt to explain matters on the gene inheritance Mendel carried out some farm experiments, and his achievement was to reveal that the only reason most inheritance seems to be a blend is that it involves more than one particle. Muller wrote that mutation does not stand as unreachable god playing its pranks upon us from some impregnable citadel in the germplasm. He wrote this after causing the genes to mutate so that offsprings could sport new deformities. Therefore living things are capable of acquiring other genes from oters.