Final answer:
All cells store hereditary information in DNA, a linear code of nucleotides. Genes are segments of DNA that determine an organism's characteristics and can vary through mutation, potentially leading to the evolution of species.
Step-by-step explanation:
All cells store their hereditary information in the same linear chemical code known as deoxyribonucleic acid (DNA). This genetic material is structured as a sequence of nucleotide bases which encode the instructions for forming all cellular components and allow for the replication of identical DNA molecules during cell division. Each species has a unique DNA sequence which assures their continuity over successive generations, and any hereditary change in this sequence, known as a mutation, can lead to the evolution of species.
The Structure and Function of DNA
DNA is a linear polymer composed of a unique sequence of nucleotide bases that are specific to each individual organism. In eukaryotes, the genome consists of several double-stranded linear DNA molecules, with a characteristic number of chromosomes specific to each species. For instance, human somatic cells contain 46 chromosomes arranged in pairs, a diploid configuration.
Genes and the Genetic Code
Genes, the fundamental units of heredity, are linearly arranged on chromosomes and are responsible for determining the specific characteristics of an organism. These genes code for proteins that orchestrate virtually every function of the cell. Traits, or the variations of characteristics, are the result of gene expression.
Continuity and Variation of Species
The genetic information stored in a cell ensures the continuity of species while allowing for variation through mutation. Over generations, mutations can accumulate, potentially leading to the evolution of species. Gregor Mendel's experiments with pea plants laid the foundation for our understanding of how traits are inherited across generations and the significance of genes in heredity.