Houstond Unit 1 Test 2


insoluble organic compounds that contain the elements carbon, hydrogen, and oxygen (CHO) which are held together by ester bonds.


The phosphate group and polar head region of the molecule is hydrophilic (attracted towater), while the fatty acid tail is hydrophobic


lipids that occur naturally in plants, animals, and fungi, with the most familiar type of animal sterol being cholesterol.


organic molecules that contain carbon, hydrogen, oxygen, and nitrogen (CHON) that are made up of chains of amino acids held together by peptide bonds.

Amino acids

the monomers of proteins that are made up of an amino group, a carboxyl group, and an R side chain.


a type of protein used to form bone and muscle that is the most abundant protein in the body.


a type of protein used to form hair and nails.

nucleic acids

organic molecules made up of the elements carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS) held together by phosphodiester bonds.


the monomers of nucleic acids and have 3 parts: - a phosphate group,- a five-carbon sugar,- and a nitrogenous base.


the elements or compounds that enter into a chemical reaction that are located to the left of the arrow.


the elements or compounds produced by a chemical reaction that are located to the right of the arrow.

Exothermic reactions

reactions where energy is released when chemical bonds are broken that usually give off heat. Exothermic reactions are also called decomposition reactions.

Endothermic reactions

reactions where energy is absorbed and stored when chemical bonds are formed. Endothermic reactions are also called synthesis reactions.

synthesis reactions

endothermic reactions that occur when smaller particles are bonded together to form larger, more complex molecules by dehydration synthesis.

decomposition reactions

exothermic reactions that occur when bonds are broken in larger molecules by hydrolysis, resulting in smaller, less complex molecules.


a substance that speeds up the rateof a chemical reaction thus reducing the energyneeded for the reaction to occur.


types of proteins that act as biologicalcatalysts.


the molecules that are acted upon by an enzyme and are the reactants of enzyme-catalyzed reactions.


occurs when a rise or fall in the pH or temperature can cause enzymes to change their shape, preventing them from fitting together in the enzyme-substrate complex.

Adenosine Triphosphate

a molecule made up of a modified nitrogen base (adenine) and three phosphates that stores energy for chemical and mechanical processes in the body.