Why are atoms not the basic unit of life instead of cells?

The cell is the basic unit of life: it is the smallest entity that can be considered a living thing. Atoms themselves, however, are not alive. But cells could not be cells without atoms.
Atoms are the building blocks of everything you see (or can't see!) around you. The Periodic Table of Elements lists all known types of atoms. These different types of atoms, called elements, have very different ways of behaving. They can interact with each other and bond together to form molecules (2 or more atoms). Millions of certain types of molecules combine in specific ways to make the four types of macromolecules found in all cells: proteins, nucleic acid (DNA, etc.), carbohydrates (sugar, starch), and lipids (fat and oils). These larger building blocks, made up of atoms, combine in very specific ways to form a cell... a little sac that has tons of chemical reactions going on inside it, which is the basic definition of life. You and I are made up of trillions of cells, but some organisms are only one single cell.
In addition, a cell can be seen with a microscope, whereas individual atoms cannot.

i dont wanna live in this planet anymore

Atoms aren't living. Cells are. Problem solved.

Basic Unit Of Life

all life form comsposed of cell

There are attributes of being alive, which a cell possesses; atoms don't

Cells are basically the smallest thing common to all organisms. Atoms are the smallest thing common to everything whether it be living or not.

Atoms aren't living but Cells are...

Atoms make up all living AND non-living things. For example: rocks are made of atoms. Are rocks alive? The answer is no because cells do not cause rocks to grow; rocks do not have cells.

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[edit] Macromolecules

The term macromolecule was coined by Nobel laureate Hermann Staudinger in the 1920s, although his first relevant publication on this field only mentions high molecular compounds (in excess of 1,000 atoms). At that time the phrase polymer as introduced by Berzelius in 1833 had a different meaning from that of today: it simply was another form of isomerism for example with benzene and acetylene and had little to do with size.Some examples of organic macromolecules are bio-polymers (carbohydrates, proteins and lipids, Polysaccharides) and synthetic polymers (plastics, synthetic fiber and rubber).
[edit] Carbohydrates

A carbohydrate (kɑ:bəˈhaɪdreɪt/) is an organic compound which has the empirical formula Cm(H2O)n; that is, consists only of carbon, hydrogen and oxygen, with a hydrogen:oxygen atom ratio of 2:1 (as in water). Carbohydrates can be viewed as hydrates of carbon, hence their name. Structurally however, it is more accurate to view them as polyhydroxy aldehydes and ketones.Historically nutritionists have classified carbohydrates as either simple or complex, however, the exact delineation of these categories is ambiguous. Today, simple carbohydrate typically refers to monosaccharides and disaccharides and complex carbohydrate meeans polysaccharides (and oligosaccharides).
[edit] a.Monosaccharides

Monosaccharides (from Greek monos: single, sacchar: sugar) are the most basic units of biologically important carbohydrates. They are the simplest form of sugar and are usually colorless, water-soluble, crystalline solids. Some monosaccharides have a sweet taste. Examples of monosaccharides include glucose (dextrose), fructose (levulose), galactose, xylose and ribose. Monosaccharides are the building blocks of disaccharides such as sucrose and polysaccharides (such as cellulose and starch). Further, each carbon atom that supports a hydroxyl group (except for the first and last) is chiral, giving rise to a number of isomeric forms all with the same chemical formula. For instance, galactose and glucose are both aldohexoses, but have different chemical and physical properties.
[edit] b.Disaccharide

A disaccharide or biose is the carbohydrate formed when two monosaccharides undergo a condensation reaction which involves the elimination of a small molecule, such as water, from the functional groups only. Like monosaccharides, disaccharides also dissolve in water, taste sweet and are called sugars.The glycosidic bond can be formed between any hydroxyl group on the component monosaccharide. So, even if both component sugars are the same (e.g., glucose), different bond combinations (regiochemistry) and stereochemistry (alpha- or beta-) result in disaccharides that are diastereoisomers with different chemical and physical properties. Depending on the monosaccharide constituents, disaccharides are sometimes crystalline, sometimes water-soluble, and sometimes sweet-tasting and sticky-feeling.
Disaccharide Unit 1 Unit 2 Bond
Sucrose (table sugar, cane sugar, beet sugar, or saccharose) glucose fructose α(1→2)
Lactulose galactose fructose β(1→4)
Lactose (milk sugar) galactose glucose β(1→4)
Maltose glucose glucose α(1→4)
Trehalose glucose glucose α(1→1)α
Cellobiose glucose glucose β(1→4)
[edit] c.Oligosaccharide

An oligosaccharide (from the Greek oligos, a few, and sacchar, sugar) is a saccharide polymer containing a small number (typically three to ten of component sugars, also known as simple sugars (monosaccharides). Oligosaccharides can have many functions; for example, they are commonly found on the plasma membrane of animal cells where they can play a role in cell-cell recognition.In general, they are found either O- or N-linked to compatible amino acid side-chains in proteins or to lipid moieties . e.g.Fructo-oligosaccharides (FOS), which are found in many vegetables, consist of short chains of fructose molecules. (Inulin has a much higher degree of polymerization than FOS and is a polysaccharide.) Galactooligosaccharides (GOS), which also occur naturally, consist of short chains of galactose molecules. These compounds can be only partially digested by humans.
[edit] d.Polysaccharides
Glycogen.