Cell Biology Part 2

Terms	Definitions
Stimulus	a change in an organism's surroundings that causes the organism to react
Cell Theory	This says that all living things are made of cells, that cells are the basic unit of structure and function and that cells only come from other cells.
Eukaryotic	cells that have a nucleus
Prokaryotic	cells that do not have a nucleus
Viruses	tiny particles, smaller than bacteria and other pathogens, which must invade living cells in order to reproduce; when they invade, the cells are damaged or destroyed in the process releasing new particles to infect other cells
Bacteria	(microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission
Unicellular	having or consisting of a single cell
Multicellular	consisting of many cells
Cell Wall	a thin membrane around the cytoplasm of a cell
Cell Membrane	a thin membrane around the cytoplasm of a cell
Mitochondria	Powerhouse of the cell, organelle that is the site of ATP (energy) production
Chloroplasts	organelles that capture the energy from sunlight and convert it into chemical energy in a process called photosynthesis
Respiration	the metabolic processes whereby certain organisms obtain energy from organic moelcules
Photosynthesis	process by which plants and some other organisms use light energy to convert water and carbon dioxide into oxygen and high-energy carbohydrates such as sugars and starches
Golgi apparatus	a net-like structure in the cytoplasm of animal cells (especially in those cells that produce secretions)
Endoplasmic Reticulum	an internal membrane system in which components of cell membrane and some proteins are constructed
Ribosome	an organelle in the cytoplasm of a living cell
Lysosome	cell organelle filled with enzymes needed to break down certain materials in the cell
Vacuole	cell organelle that stores materials such as water, salts, proteins, and carbohydrates
Cytoskeleton	a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence
Nucleus	a part of the cell containing DNA and RNA and responsible for growth and reproduction
Nucleolus	The organelle where ribosomes are made, synthesized and partially assembled, located in the nucleus
Chromosomes	threadlike structures made of DNA molecules that contain the genes
DNA	(biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix
ATP	main energy source that cells use for most of their work