Terms : Hide Images
| 7992099647 | Atom | The smallest unit of ordinary matter that has the properties of a chemical element. |  | 0 |
| 7992099648 | Molecule | The smallest particle in a chemical element or compound. These particles are made up of two or more atoms that are held together by chemical bonds. |  | 1 |
| 7992099649 | Covalent bond | A chemical bond that involves the sharing of electron pairs between atoms. |  | 2 |
| 7992099650 | Ionic bond | A type of chemical bond that involves the electrostatic attraction between oppositely charged ions. |  | 3 |
| 7992099651 | Hydrogen bond | The attractive force between the hydrogen attached to an electronegative atom of one molecule and an electronegative atom of a different molecule. |  | 4 |
| 7992099652 | Macromolecule | A very large molecule, such as protein, commonly created by polymerization of smaller subunits (monomers). They are sometimes composed of thousands or more atoms. |  | 5 |
| 7992099653 | Organelle | Structures with specialized functions suspended in the cytoplasm of a eukaryotic cell. |  | 6 |
| 7992099654 | Tissue | Distinct types of material which make up organisms and consist of specialized cells and their products. |  | 7 |
| 7992099655 | Organ system | A group of organs that work together to perform one or more functions. |  | 8 |
| 7992099656 | Atom, molecule, macromolecule, organelle, cell, tissue, organ, organ system, organism | Name the levels in the hierarchy of life from atoms to organisms. |  | 9 |
| 7992099657 | Carbohydrate | A biological molecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms. Examples are sugar, cellulose, chitin and starch. |  | 10 |
| 7992099658 | Nucleic acid | A large biological molecule made up of nucleotides. Examples are DNA and RNA. |  | 11 |
| 7992099659 | Protein | A large biological molecule composed of one or more long chains of amino acids. Examples include all enzymes, collagen, keratin, insulin, immunoglobulins, muscle fibers. |  | 12 |
| 7992099660 | Lipid | A large biological molecule made up of fatty acids that are not soluble water. Examples include fats, waxes, and cholesterol. |  | 13 |
