diffusion
the movement of molecules from areas of greater concentration to areas of lesser concentration
osmosis
the diffusion of water across the cell membrane
active transport
a process that allows molecules to move across the cell membrane from lower to higher concentrations.
photosynthesis
a process where plants use the energy of sunlight to produce carbohydrates
color
how we perceive the energy of light
pigment
a molecule that absorbs some colors of light and reflects others
chlorophyll
the main pigment used in photosynthesis that absorbs blue and red light and reflects green light
cellular respiration
the process in which the chemical bonds of energy-rich molecules are converted into a form of energy that cells can use
ATP
a molecule that stores and transfers energy within cells.