CONCEPTS OF MATTER AND ENERGY

• Energy is the ability to do work.
• Matter is anything that occupies space and has mass.
• Chemical energy is stored in the bonds of chemical substances.
• Electrical energy results from the movement of charged particles.
• Mechanical energy is energy directly involved in moving matter.
• Radiant energy travels in waves; that is, it is the energy of the electromagnetic spectrum.
• Oxygen is a major component of both organic and inorganic molecules and is essential to the oxidation of glucose and other food fuels, during which cellular energy (ATP) is produced.
• Carbon is the primary element in all organic molecules, including carbohydrates, lipids, proteins, and nucleic acids.
• Hydrogen is a component of most organic molecules and as an ion (a charged atom), it influences the pH of body fluids.
• Nitrogen is a component of proteins and nucleic acids (genetic material).
• Calcium is found as a salt in bones and teeth; in ionic form, it is required for muscle contraction, neural transmission, and blood clotting.
• Isotope - atoms that have the same number of protons and electrons.
• ↑ temperature - increase the kinetic energy of the molecules, which in turn move more rapidly and collide more forcefully.
• ↑ concentration of reacting particles - ncreases the number of collisions because of increased numbers of reacting particles.
• ↓ particle size - smaller particles have more kinetic energy and move faster than larger ones, they take part in more collisions.
• The presence of catalysts - decreases the amount of energy the molecules need to interact by holding the reactants in the proper positions to interact.
• Water - most abundant inorganic compound in the body
• Cushioning - water serves a protective function. (ex. Cerebrospinal fluid protects the brain from physical trauma, and amniotic fluid protects a developing fetus)
• organ is a structure composed of two or more tissue types that performs a specific function for the body.
• An organ system is a group of organs that work together to accomplish a common purpose. 
• integumentary system - is the external covering of the body, or the skin. It waterproofs the body and cushions and protects the deeper tissues from injury. 
• Muscular System - consists of skeletal muscles which are attached to bones and allow movement of the body parts.
• Skeletal system consists of bones, cartilages, ligaments, and joints. It supports the body and provides a framework that the skeletal muscles use to cause movement. Hematopoiesis or formation of blood cells, takes place within the cavities of the skeleton. 
• The skeletal muscles form the muscular system. These muscles are distinct from the muscles of the heart and of other hollow organs, which move fluids or other substances along definite pathways within the body; responsible for movement 
• nervous system is the body’s fast-acting control system. It consists of the brain, spinal cord, nerves, and sensory receptors.
• Respiratory system - brings oxygen into the body and removes carbon dioxide through breathing. It also helps maintain homeostasis by controlling acid-base balance and removing waste products like carbon monoxide.
• the endocrine system controls the body activities, but it acts much more slowly; release hormones
• The cardiovascular system consists of the heart and blood vessels.
• Using blood as the transporting fluid, the cardiovascular system carries oxygen, nutrients, hormones, and other substances to and from the tissue cells where exchanges are made.
• The role of the lymphatic system complements that of the cardiovascular system.
• Its organs include lymphatic vessels, lymph nodes, and other lymphoid organs such as the spleen and tonsils; it keeps body fluid levels in balance and defends the body against infections.
• The respiratory system is to keep the body constantly supplied with oxygen and to remove carbon dioxide.
• The digestive system's role is to break down food and deliver the products to the blood for dispersal to the body cells.
• The urinary system removes the nitrogen-containing wastes from the blood and flushes them from the body in urine.
• This system, often called the excretory system, is composed of the kidneys, ureters, bladder, and urethra.
• The function of the reproductive system is to produce offspring.
• Superior (cranial or cephalic) refers to the head end or upper part of a structure or the body, above.
• Inferior (caudal) refers to a structure or the body, below the head end or toward the lower part of the body.
• Anterior (ventral) refers to the front of the body, in front of.
• Posterior (dorsal) refers to the backside of the body, behind.