Ribonucleic acid ,or RNA, is one of the three major macromolecules (along with DNA and proteins) that are essential for all known forms of life. Like DNA, RNA is made up of a long chain of components called nucleotides.
The basic building block of any substance is the atom. Every element and compound is made up of one or more atoms. In making up of the atom an atom is made up of only one nucleus but can have several shells. Within the nucleus protons and neutrons are present.Every element has a specific number of protons.toms are tiny units of matter. All matter are made up of matter that occupies space and is made up of atoms. Atoms are the smallest particle of an element that can join up in whole numbers to form molecules.
1 Cells are the basic structural and functional unit of all life. 2  Examples include red blood cells and nerve cells. 3  Tissues. 4  TissuesA group of cells that share a common structure and function and that work together. are groups of cells that share a common structure and function and work together. cell can be thought of as a mini-organism consisting of tiny organs called organelles. The organellesA structural or functional unit in a cell that is constructed from several macromolecules bonded together. are structural and functional units constructed from several macromolecules bonded together.