ap bio quiz unit 2B

enzyme

biological catalyst that speeds up the reaction by reducing the amount of activation energy required. The reaction may be spontaneous w/o the catalyst, but it would be very slow.

Denaturation

breaking down of quaternary, tertiary, and secondary structures. Ruins the shape of the protein, renders it useless. Causes: high temperatures, low pH

amino acids

building blocks of proteins. 20 different amino acids on earth. All amino acids have same backbone structure: amine group on one end, carboxyl group on the other end. The unique functional group side chains distinguish one amino acid from another.

DG

change in free energy between products & reactants

proteins

characterized by amine & carboxyl groups. Functions: metabolism, enzymes, structural components, regulatory molecules

dehydration synthesis

combining of monomers to create polymers. Water is created, as OH and H are removed from the monomers to create the bonds.

Nucleotide

consists of a phosphate group, sugar, and nitrogen base

organic molecules

contain skeleton structures of carbon with hydrogen and oxygen

chitin

contains nitrogen, found in fungi cell walls & arthropod exoskeletons

nucleic acids

macromolecules containing hydrogen, oxygen, nitrogen, carbon, and phosphorus

energy storage

one function of polysaccharides is as an ____________________ macromolecule that is hydrolyzed as needed.

Deoxyribose

pentose joined to the nitrogen base in dna

ribosomes

site of protein synthesis

complex carbohydrates

starches, cellulose, glycogen, chitin, lipids

competitive inhibition

substance that resembles the normal substrate competes with the substrate for the active site

primary structure of protein

the amino acid sequence of the polypeptide chain

functional groups

the components of organic molecules that are most commonly involved in chemical reactions

optimal conditions

the pH, temperature, and concentration under which the enzyme is most active & efficient

enzyme-substrate complex

A temporary complex formed when an enzyme binds to its substrate molecule(s).

metabolism building bonds

-dehydration or condensation synthesis -anabolic -stores energy -endergonic

metabolism breaking bonds

-hydrolysis -catabolic -releases energy -exergonic

Cholesterol

A lipid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids. precursor of steroids (hormones), always characterized by four fused rings in a lipid hydrocarbon skeleton

endergonic reaction

A non-spontaneous chemical reaction in which free energy is absorbed from the surroundings. (photosynthesis)

negative feedback

A primary mechanism of homeostasis, whereby a change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation.

exergonic reaction

A spontaneous chemical reaction in which there is a net release of free energy. (cellular respiration)

noncompetitive inhibitor

A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing its conformation so that it no longer binds to the substrate.

positive feedback

A type of regulation that responds to a change in conditions by initiating responses that will amplify the change. Takes organism away from a steady state.

Macromolecules

A very large organic molecule composed of many smaller molecules (carbohydrates, lipids, proteins, nucleic acid)

ATP (adenosine triphosphate)

An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reactions in cells.

tertiary structure of protein

Defined by the hydrophilic and hydrophobic interactions between R groups of amino acid chains. disulfide bridges, van der waals, hydrogen bonds

Carbon covalent bonds

Octet Rule # 3 - Share electrons

Monosaccharides

Single sugar molecules

factors affect enzyme activity

Temperature -Extreme temperatures will denature the enzyme, rendering it inactive -Temperatures of enzymes or substrates affect activity •pH -Extreme low or high pH denatures enzyme and renders it inactive -Some enzymes have optimal pH •Concentration -Density of either enzyme or substrate will affect the activity

allosteric regulation

The binding of a regulatory molecule to a protein at one site that affects the function of the protein at a different site.

quaternary structure

The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits.

activation energy

The initial input (cost) of energy required to begin catabolism. Amount of energy needed to destabilize the bonds of a large molecule. Catalysts reduce the amount of activation energy.

Isomers

Two different molecules that have the same chemical formula

EA

activation energy, required to start reaction

secondary structure of protein

alpha helix and beta pleated sheet

Carbohydrates

are characterized by H, OH, and Carbonyl Groups. immediate energy, structural components

cellulose

different bonding, every other glucose is flipped, form sheets, very stable, cannot be digested by humans

Mitochondria

double helix structure site

protease

enzyme that digests protein

starches

fairly long polymers of glucose, branched

synthesis

formation of polypeptide from singular amino acids. Peptide bond forms between the amine group of one amino acid and the carboxyl group of the other amino acid. They line up end-to-end with their side chains hanging off the side.

glycogen

glucose storage in animals; stored in livers

ringed monosaccharides

glucose, dextrose, fructose

Enantiomers

isomers that are mirror images of each other

lipids

long chain hydrocarbons, nonpolar, hydrophobic Functions: long-term energy storage, insulation, cell membranes