Cell Parts
cell membrane
double-layer of phospholipids that forms a boundary between a cell and the surrounding environment and controls the passage of materials into and out of a cell
facilitated diffusion
diffusion of molecules assisted by protein channels that pierce a cell membrane
DNA
molecule that stores genetic material in all organisms.
light-dependent reactions
part of photosynthesis that absorbs energy from sunlight and transfers energy to the light-independent reactions.
carbohydrate
molecule composed of carbon, hydrogen, and oxygen; includes sugars and starches.
cytoplasm
jellylike substance inside cells that contains molecules and in some cells organelles.
active transport
energy-requiring movement of molecules across a membrane from a region of lower concentration to a region of higher concentration
RNA
nucleic acid molecule that allows for the transmission of genetic information and protein synthesis
light-independent reactions
part of photosynthesis that uses energy absorbed during the light-dependent reactions to synthesize carbohydrates
protein
polymer composed of amino acids linked by perptide bonds; folds into a particular structure depending on bonds between amino acids
ribosome
organelle that links amino acids together to form proteins
passive transport
the movement of substances across a cell membrane without the use of energy by the cell
transcription
process of copying a nucleotide sequence of DNA to form a complementary strand of mRNA
cellular respiration
process of producing ATP by breaking down carbon-based molecules when oxygen is present.
lipid
nonpolar molecule composed of carbon, hydrogen, and oxygen; includes fats and oils
nucleus
organelle composed of a double membrane that acts as the storehouse for most of a cell's DNA
osmosis
diffusion of water molecules across a semipermeable membrane from an area of higher water concentration to an area of lower water concentration
translation
process by which mRNA is decoded and a protein is produced
Kreb's cycle
process during cellular respiration that breaks down a carbon molecule to produce molecules that are used in the electron transport chain.
amino acid
a molecule that makes up proteins; composed of carbon hydrogen, oxygen, nitrogen, and sometimes sulfur
rough endoplasmic reticulum
.parts of the endoplasmic reticulum to which ribosomes are attached on the cytoplasmic side
phospholipid bilayer
plasma membrane layers composed of phospholipid molecules arranged with polar heads facing the outside and nonpolar tails facing the inside
mRNA
form of RNA that carries genetic information from the nucleus to the cytoplasm, where it serves as a template for protein synthesis
anerobic
process that does not require oxygen to occur.
nucleic acid
polymer of nucleotides; the genetic material of organisms.