II. Biological Background

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Chromosome

All living organisms consist of cells. In each cell there is the same set of chromosomes. Chromosomes are strings of DNA and serve as a model for the whole organism. A chromosome consists of genes, which are blocks of DNA. Each gene encodes a particular protein. In simple terms, each gene can be said to encode a trait, for example eye color. Possible settings for a trait (e.g. blue, brown) are called alleles. Each gene has its own position in the chromosome. This position is called locus.

Complete set of genetic material (all chromosomes) is called genome. The particular set of genes in the genome is called the genotype. With later development after birth, the genotype becomes the basis for the organism's phenotype, its physical and mental characteristics, such as eye color, intelligence, and so on.

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Reproduction

During reproduction, recombination (or crossover) occurs first. Genes from the parents are combined in some way to form a new chromosome. The newly created offspring can then be mutated. Mutation means that the elements of DNA are changed slightly. These changes are mainly caused by errors in copying genes from the parents.

The fitness of an organism is measured by its success in life.