| A | B |
|---|
| diffusion | process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated |
| selective permeability | property of biological membranes that allows only certain substances to pass through them |
| osmosis | diffusion of water through a selectively permeable membrane |
| facilitated diffusion | movement of specific molecules across cell membranes through protein channels |
| active transport | energy-requiring process that moves material across a cell membrane against a concentration difference |
| endocytosis | process by which a cell takes material into the cell by infolding of the cell membrane |
| phagocytosis | process in which extensions of cytoplasm surround and engulf large particles and take them into the cell |
| exocytosis | process by which a cell releases large amounts of material |
| autotroph | organism that can capture energy from sunlight or chemicals and use it to produce its own food from inorganic compounds; also called a producer |
| heterotroph | organism that obtains energy from the food it consumes; also called a consumer |
| adenosine triphosphate (ATP) | one of the principal chemical compounds that living things use to store energy |
| photosynthesis | process by which plants and some other organisms use light energy to power chemical reactions that convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches |
| calorie | term used by scientists to measure the energy stored in foods |
| cellular respiration | process that releases energy by breaking down food molecules in the presence of oxygen; made up of glycolysis, the Krebs cycle, and the electron transport chain |
| fermentation | process by which cells release energy in the absence of oxygen |
| anaerobic | process that does not require energy |
| aerobic | process that requires oxygen |
