Chapter 3 Vocab Flashcards
Cytoplasm
Jellylike substance inside cells that contains molecules and in some cells, organelles
Cell theory
One of the first unifying concepts in biology; theory that states that all organisms are made of cells, all cells are produced by other living cells, and the cell is the most basic unit of life
Organelles
membrane-bound structure that is specialized to preform a distinct process within a cell
Prokaryotic cells
Cell that does not have a nucleus or other membrane-bound organelles
Eukaryotic cells
Cell that has a nucleus and other membrane-bound organelles
Cytoskeleton
Network of proteins, such as microtubules and micro filaments, inside a eukaryotic cell that supports and shapes the cell
Nucleus
Organelle composed of a double membrane that acts as the storehouse for most of a cells DNA
Endoplasmic reticulum
Interconnected network of thin folded membranes that produce, process, and distribute proteins
Vesicles
Small organelle that contains and transports materials within the cytoplasm
Mitochondrion
Bean-shaped organelle that supplies energy to the cell and has its own ribosomes and DNA
Vacuole
Organelle that is used to store materials, such as water, food, or enzymes, that are needed by the cell
Lysosomes
Organelle that contains enzymes
Centrioles
Small, cylinder-shaped organelle made of protein tubes arranged in a circle; aids mitosis
Cell wall
Rigid structure that gives protection, support, and shape to cells in plants, algae, fungi, and bacteria
Chloroplast
Organelle composed of numberous membranes that are used to covert solar energy into chemical energy; contains chlorophyll
Golgi apparatus
stack of flat, membrane enclosed spaces containing enzymes that process, sort, and deliver proteins
Ribosomes
Organelle that links amino acids together to form proteins
Cell membrane
Plasma membrane; double-layer of phospholipids that forms a boundary between cell and the surrounding environment and controls the passage of materials into and out of a cell
Phospholipid
Molecule that forms a double-layered cell membrane; consists if a gycerol, a phosphate group, and two fatty acids
Fluid mosaic model
A model that describes the arrangement and movement of the molecules that make up a cell membrane
Selective permeability
condition or quality of allowing some, but not all, materials to cross a barrier or membrane
Receptor
Protein that detects a signal molecule and performs an action in response
passive transport
movement of molecules across the cell membrane without energy input from the cell
diffusion
movement of dissolved molecules in a fluid or gas from a region of higher concentration to a region of lower concentration
concentration gradient
difference in the concentration of a substance from one location to another
osmosis
diffusion of water molecules across a semipermeable membrane from an area of higher water concentration to an area of lower water concentration
isotonic
solution that has an equal concentration of dissolved particles compared with another solution
hypertonic
solution that has a higher concentration of dissolved particles comared with another solution
hypotonic
solution that has a lower concentration of dissolved particles compared with another solution
facilitated diffusion
diffusion of molecules assisted by protein channels that pierce a cell membrane
Active transport
Energy-requiring movement of molecules across a membrane from a region of lower concentration to a region of higher concentration
Endocytosis
Uptake of liquids or large molecules into a cell by inward folding of the cell membrane
Exocytosis
Realease of substances out a cell by the fusion of a vesicle with the membrane
Phagocytosis
Uptake of a solid particle into a cell by engulfing the particle
