the generalization that all living things are composed of cells, and that cells are the basic unit of structure and function of living things.
thin outer boundary which defines the boundary of the cell and regulates the traffic of chemicals between the cells and its surroundings.
has a nucleus surrounded by its own membrane, and has other internal organelles bounded by membranes. ex. plants, fungi, prosists, and animal
the net movement of the particles of a substance from where they are concentrated to where they are less concentrated.
selectively permeable membrane
allows some substances to cross the membrane more easily then others and blocks the passage of some substances altogether. this is PASSIVE TRANSPORT.
diffusion across a membrane, because no energy is needed to do this. *high concentration to low concentration
transport proteins provide a pathway for certain molecules to pass. (facilitate = to help)
a process when a cell expands energy to move molecules or ions across a membrane. during active transport a specific protein pumps a solute across a membrane, usually the opposite direction in which diffusion travels. LOW CONCENTRATION --> HIGH CONCENTRATION
exiting the products from the cell by fusing with the plasma membrane and spilling its contents out of the cell.
reverse process of exocytosis, takes material into a cell within vesicles that bud inward from the plasma membrane
surrounds the nucleus in a pair of membranes, substances made in the nucleus move into the cell's cytoplasm through tiny holes or pores in the nuclear envelope.
within the cytoplasm of a cell is an extensive network of membranes, produces and enormous amount of molecules. main manufacturing and transportation facilities in the celll factory.
has ribosomes lined on the outside of the membrane., ribosomes produce proteins, also produce proteins which are packaged in vesicles.
the golgi apparatus
an organelle that modify, stores, and routes proteins and other chemical products to their next destinations.
membrane bound sacs which contain digestive enzymes that can break down such macromolecules as proteins, nucleic acids and polysaccharides.
they are in eukaryotic cells, and sites where cellular respiration occurs. In this process it releases energy from sugars and certain other organic molecules and then uses it in the formation of another organic molecule called ATP.