By studying the fossil record we can tell how long life has existed on Earth, and how different plants and animals are related to each other. Often we can work out how and where they lived, and use this information to find out about ancient environments.
The frontal bone can also be known as the forehead
The production of egg and sperm cells follows a certain sequence of events.
The correct order of those events are:
MEIOSIS, CELL DIFFERENTIATION, MATURE GAMETES.
Meiosis is defined as the process wherein a single cell is divided twice to produce four cells that contains half the original amount of genetic information.
Cell differentiation is defined as the process wherein the less specialized cell becomes a more specialized cell. The haploid cells are the end result of meiosis. They must undergo cell differentiation before they can become mature gametes.
DNA is considered the molecule of life because it contains the instructions that ensure the continuity of life. Employment of DNA to code for protein is the basis of all life on earth.
In all living things, inherited DNA is used to code for amino acids which when joined or linked together in a deliberate specific manner form polypeptides which make up proteins. These proteins are responsible for structure and function of cells.
For example DNA provides information to make four polypeptide (two beta and two alpha ) chains which make up hemoglobin, the protein that functions as the oxygen carrier in red blood cells. In summary,
DNA → protein → trait, and that relationship is the physical basis of life.
