Biomolecules and Cells


Organic molecules that are produced by a living organism


Carbon based


Big" biomolecules, the four important ones are carbohydrates, lipids, proteins, and nucleus acids


Single subunits of a polymer


Chains of monomers

Saturated fats

Fats that have only single Carbon bonds in the tail; solid at room temperature

Unsaturated fats

Fats that have at least one double Carbon bond in the tail; liquid at room temperature


Any sugar that can't be simplified (carbohydrate monomer) ex. Glucose


Any sugar that is made out of 2 monosaccharides (carbohydrate dimer)


Any sugar that is made out of more than 2 monosaccharide (carbohydrate polymer)


Lipids or fats that contain Phosphorus; major components of the cell membrane; interact in a certain way with water

Amino acids

Monomers of proteins; 20 amino acids

Primary protein structure

Sequence of a chain of amino acida

Secondary protein structure

Occurs when the sequences of amino acids are linked by hydrogen bonds

Tertiary protein structure

Occurs when certain attractions are present between alpha helices and pleated sheets

Quaternary protein structure

A protein consisting of more than one amino acid chain


Made of Carbon, Hydrogen, and Oxygen; functional group is -OH; found in cytoplasm; lots of energy but fast energy; sugars in 1:2:1 ratio


Made of Carbon, Hydrogen, Oxygen and sometimes Phosphorus; functional group is C=O; found in cell membrane; long term energy storage; heads are polar, tails are non-polar


Made out of Carbon, Hydrogen, Oxygen, Nitrogen and sometimes Sulfur; made out of amino acids; amino groups and carboxyl group; cell membrane components; found in hair teeth, enzymes and skin

Nucleic Acids

Made of Carbon, Hydrogen, Oxygen, Nitrogen and Phosphorus; monomer is nucleotide; found in nucleus; DNA and RNA


Made up of a phosphate group, a sugar and a nitrogenous base


Jelly-like material found inside the cell
Surrounds and suspends all the organelles
Composed of water, salts, and organic compounds


Intermed fibers
Aids in maintaining cell structure/ shape and most importantly movement

Rough Endoplasmic Reticulum (ER)

Continuation of the nuclear enveloped that synthesizes proteins

Smooth Endoplasmic Reticulum

Continuation of the nuclear envelope that makes lipids and steroid hormones

Golgi Body

Transports proteins to cell membrane from the Golgi apparatus

Golgi Apparatus

Stacked organelles that receive proteins from ER
Packages, processes and secretes proteins
Proteins are tweaked, then packaged and sent off for delivery


Wreaking crew of eukaryotic cells
Contains enzymes that are only active within it
Formed from Golgi
Breaks down old/damaged cell parts


Small in animal cells-plays role in intracellular digestion and waste removal
Larger in plants-plays a role in turger (water) pressure, storing nutrients and waste


Membrane bound sacs that move cellular secretions from place to place

Mitochondria (mitos)

Makes energy for cells (ATP)
Cell respiration occurs here
All are inherited from your mother
Have their own DNA and can be used to follow maternal lines


Obvious organelle-responsible for containing DNA and sending messages encoding protein to ER
Contain DNA in dense chromatin/chromosomes


Bundle of chromatin in the nucleus-contains DNA
Makes ribosomes

Cell membrane

Made of phospholipid bilayer
Fluid mosaic membrane
Has different types of proteins embedded in it
Cholesterol keeps the membrane stable
Semi-permeable (only some items can pass through easily)


Organelles that make proteins
Most numerous organelle in cell
Composed of Nucleic acids and protein subunits
May be attached to the ER or may be floating in cytoplasm


Contains chlorophyll
Site of photosynthesis in higher plants
Double membraned stacks of thylakoid

Cell Wall

Rigid protective coat made of cellulose and some proteins
Aids in maintaining shape of cell
Can withstand lots of internal water pressure (turgor)


Helps with cell division in animal cells and formation of the spindle fibers that separate the chromosomes during cell division (mitosis).

Eukaryotic cells

Cells that contain nuclei (ex. plant and animal cells)

Prokaryotic cells

Cells that don't contain nuclei (ex. bacteria)


Whip-like structure that allows a cell to move
Found in prokaryotic and eukaryotic cells


Moves liquid over the surface of the cell (e.g., driving particle-laden mucus toward the throat).

Active channel proteins

Bind molecules/ions at one side and allow passage
Uses the cell's energy to do this
For bigger molecules that go against the concentration gradient

Passive channel proteins

Lets in big molecules and ions that can't pass through the membrane
Goes with the concentration gradient
Doesn't use the cell's energy

Marker/Self-recognition proteins

Signal the immune system to leave the cell alone
Identifies cell types

Receptor proteins

Receives hormones and electrical messages
Signals to the inside of the cell to take action

Anchor proteins

Attaches the cell to other cells
Attaches the cytoskeleton to the membrane

Concentration gradient

Transport of water and particles that depends on a difference in number of molecules in adjacent regions

Molecular motion

Molecules are always moving


When the number of particles is equal in adjacent regions
The particles still move, but there is no NET movement in any one direction

Passive transport

Movement is within the concentration gradient (high??low)
No energy is used by cell
Molecules may go through passive transport proteins


A type of passive transport


A type of passive transport that is about any molecule


More solute outside the cell than inside


Less solute outside the cell than inside


Same concentration of solute as inside the cell


Likes water


Repels water

Active transport

Pumping of specific particles across a membrane
Uses a transport protein
Against the concentration gradient (low??high)
Energy is spent by the cell
Occurs in one direction


Close to the actual or true value


The degree of exactness, or the scale of the measurement

Surface area to volume ratio

Large surface area and small volume results in more efficient diffusion