Difference Between Cell And Atom
The cell is the basic unit of life. All living things consist of cells. The simplest consist of a single cell. Plants and animals consist of many cells. The human body consists of billions upon billions.
Most cells are microscopic. Eggs are an exception. Indeed, ostrich eggs are the world’s largest cells by volume. The smallest are bacteria. These are simple, one-celled organisms. Their bodies average one-tenth the size of a human cell and are just a few micrometers long. (There are 25,000 micrometers in an inch.)
In plants and animals, cells must cooperate to sustain life. Plant and animal cells also specialize. Muscle cells, for example, expand and contract. The eye’s retinal cells sense light. Nerve cells carry electrical messages.
Some cells survive for an organism’s entire lifespan. But most are constantly dying off and being replaced. Cells replace themselves by dividing.
In certain kinds of cell division, a “parent” cell gives rise to identical “daughter” cells. For example, a parent bacterial cell splits into two daughter cells by a process called binary fission. A plant or an animal cell may also split into two identical daughter cells. However, it would use a process called mitotic cell division.
Reproductive cells are created by a process called meiotic cell division. In this process, a single parent cell gives rise to four reproductive cells.
Atom, traditionally, the smallest and most fundamental building block of matter. The word comes from the Greek atomos, meaning “indivisible.” In present-day usage “atom” is the name for a particular subunit of matter—not at all the smallest—consisting of an elaborate organization of particles into which it can be divided. However, the definition is inadequate because some of the characteristics of materials depend on the group properties of atoms even when the atoms are of the same kind. For instance, atomic hydrogen composed of individual atoms has different chemical properties from the usual molecular hydrogen gas composed of double hydrogen atoms bound together.