| A | B |
|---|
| Levels of Organization | Hierarchy of complexity in the body |
| Chemical Level | Simplest level of organization that includes atoms and molecules that form the basis of all body structures |
| Cellular Level | Level of organization that includes molecules combining to form cells, the basic units of life |
| Tissue Level | Level of organization that includes groups of similar cells working together |
| Organ Level | Level of organization that includes different tissues combined to perform specific functions |
| Organ System Level | Level of organization that includes organs working together to perform major body functions |
| Organism Level | Highest level if organization that includes complete living human beings |
| Chemistry | Study of matter and how it changes |
| Matter | Anything that has mass and takes up space |
| Element | Pure substance made of one type of atom; building blocks of matter |
| Atom | Smallest unit of an element that retains its properties |
| Molecule | Two or more atoms bonded together |
| Ion | Atom or molecule that has gained or lost electrons and has a positive or negative charge |
| Chemical Reaction | Process where substances are converted into new substances |
| Enzyme | Molecule that speeds up chemical reactions without being used up or changed; identified by suffix -ase |
| Metabolism | Sum of all chemical reactions in the body |
| Catabolism | Breakdown of larger molecules into smaller ones releasing energy |
| Anabolism | Building of new, larger molecules from smaller ones |
| Organic Molecules | Molecules containing carbon that are found in living organisms |
| Inorganic Molecules | Molecules that usually do not contain carbon |
| Water | Most abundant compound in the body essential for many functions |
| Solvent | Substance that dissolves other substances |
| Characteristics of Life | Shared traits that define living organisms |
| Organization | Characteristic that living organisms have structure and order |
| Reproduction | Characteristic of the ability to produce offspring and pass on genetic material |
| Growth and Development | Characteristic of changes in an organism over through various life stages |
| Response to Stimuli | Characteristic of the ability to react to internal or external changes, such as light or heat |
| Homeostasis | Characteristic of the maintenance of a stable internal environment |
| Adaptation and Evolution | Characteristic of the process of change to adapt to an environment that can create traits that carry over generations |
| Feedback Loop | Cycle of monitoring, response, and adjustment in the body |
| Negative Feedback Loop | Feedback loop that reverses changes to restore balance or stability, such as body temperature regulation |
| Positive Feedback Loop | Feedback loop that intensifies changes temporarily for a specific purpose, such as childbirth contractions |
| Trace Elements | Elements required in very small amounts to activate enzymes and support body functions |
| Major Elements | Elements making up most of body mass - oxygen, carbon, hydrogen, nitrogen |
| Proton | part of an atom that has a positive charge |
| Electron | part of an atom that has a negative charge |
| Neutron | part of an atom that has a neutral charge |
| Functions of water | solvent; temperature regulation; cushioning; transport of nutrients and waste; enabling chemical reactions |
| Oxygen, carbon, hydrogen and nitrogen | Four most abundant elements in the human body |
