Question | Answer |
cell theory | all organisms are made of cells, all cells are made from other living cells, and the cell is the most basic unit of life |
cytoplasm | a jellylike substance made up of molecular building blocks |
organelles | structures specialized to perform distinct functions in a cell |
prokaryotic cells | cells that don't have a nucleus or other membrane-bound organelles |
eukaryotic cells | cells that have a nucleus and other membrane-bound organelles |
cytoskeleton | a flexible network of proteins that provide structural support for the cell |
nucleus | the storehouse for most of the genetic information, or DNA, in your cells |
endoplasmic reticulum | an interconnected network of thin, folded membranes |
ribosomes | tiny organelles that link amino acids together to form proteins |
Golgi apparatus | consists of closely layered stacks of membrane-enclosed spaces that process, sort, and deliver proteins |
vesicles | a general name used to describe small, membrane-bound sacs that divide some materials from place to place within the cell |
mitochondria | the powerhouse of a cell |
vacuole | a fluid-filled sac used for the storage of materials needed by a cell |
lysosomes | membrane-bound organelles that contain enzymes |
centrioles | cylinder-shaped organelles made of short microtubules arranged in circles |
cell wall | a rigid layer that gives protection, support, and shape to the cell |
chloroplasts | organelles that carry out photosynthesis, a series of complex chemical reactions that convert solar energy into energy-rich molecules the cell can use |
cell membrane | aka the plasma membrane; forms a boundary between a cell and the outside environment and controls the passage of materials into and out of a cell |
phospholipid | a molecule composed of three basic parts: a charged phosphate group, glycerol, and two fatty acid chains |
fluid mosaic model | model that describes the arrangement of the molecules that make up a cell membrane |
selective permeability | when a cell membrane allows some, but not all, materials to cross |
receptor | a protein that detects a signal molecule and performs an action in response |
passive transport | the movement of molecules across a cell membrane without energy input from the cell |
diffusion | the movement of molecules in a fluid or gas from a region of higher concentration to a region of lower concentration |
concentration gradient | the difference in the concentration of a substance from one location to another |
osmosis | when water molecules move across a semipermeable membrane from an area of higher water concentration to an area of lower water concentration |
isotonic | term used to describe a solution that has a solute concentration equal to the solute concentration inside a cell |
hypertonic | term used to describe a solution that has a solute concentration higher than the solute concentration inside a cell |
hypotonic | term used to describe a solution that has a solute concentration lower than the solute concentration inside a cell |
facilitated diffusion | the diffusion of molecules across a membrane through transport proteins |
active transport | drives molecules across a membrane from a region of lower concentration to a region of higher concentration |
endocytosis | the process of taking liquids or fairly large molecules into a cell by engulfing them in a membrane makes a pocket around a substance |
phagocytosis | a type of endocytosis in which the cell membrane engulfs large particles |
exocytosis | the opposite of endocytosis; the release of substances out of a cell by the fusion of a vesicle with the membrane |