Chapter 2: Chemistry Comes Alive Review

Which of the following is the primary energy-transferring molecule in cells? a.) ATP b.) NADH c.) adenine d.) DNA

a.) ATP

Which of the following is FALSE regarding DNA? a.) DNA carries out the orders for protein synthesis issued by RNA b.) the DNA molecule is coiled into a spiral staircase-like structure called a double helix c.) DNA replicates itself before cell division, ensuring that all genetic information in the descendant cells is identical d.) DNA provides the basic instructions for building every protein in the body

a.) DNA carries out the orders for protein synthesis issued by RNA

Which of the following factors would speed up the rate of a chemical reaction? a.) a high concentration of reagents b.) removal of the biological catalysts c.) lower temperature d.) large particles

a.) a high concentration of reagents

When atoms or molecules combine to form larger, more complex molecules, the process is known as __________. a.) anabolism b.) exchange c.) decomposition d.) catabolism

a.) anabolism

Chemical bonds __________. a.) are energy relationships between the electrons of the reacting atoms b.) are energy relationships between the protons of the reacting atoms c.) are energy relationships between the neutrons of the reacting atoms d.) are physical structures that hold atoms together

a.) are energy relationships between the electrons of the reacting atoms

pH is a concentration unit used to measure the concentration of __________. a.) hydrogen ions in a solution b.) hydroxyl ions in a solution c.) isotopes in a solution d.) anions in a solution

a.) hydrogen ions in a solution

The outermost energy shell of an atom is known as its __________. a.) valence shell b.) energy level c.) electron shell d.) orbital model

a.) valence shell

Ninety-six percent of body weight is made up of __________ elements. a.) 92 b.) 4 c.) 112 d.) 20

b.) 4

The monomers of proteins are __________. a.) steroids b.) amino acids c.) nucleic acids d.) monosaccharaides

b.) amino acids

Enzymes __________the rate of a chemical reaction by __________ the activation energy. a.) increase; raising b.) increase; lowering c.) decrease; lowering d.) decreasing; raising

b.) increase; lowering

The building blocks (monomers) of RNA and DNA are __________. a.) phosphate groups b.) nucleotides c.) ribose sugars d.) bases

b.) nucleotides

The sequence of amino acids in a protein constitutes the __________ structure of the protein. a.) tertiary b.) primary c.) quaternary d.) secondary

b.) primary

A homogenous mixture of gases, liquids, or solids is referred to as a __________. a.) solute b.) solution c.) solvent d.) suspension

b.) solution

In hydrolysis, __________. a.) a reactant accepts electrons b.) a molecule of water is removed when proteins are synthesized from smaller molecules c.) a molecule of water is added for each bond broken d.) electrons are lost from a reactant

c.) a molecule of water is added for each bond broken

Each known element is designated with a one- or two-letter chemical shorthand known as the __________. a.) number b.) mass unit c.) atomic symbol d.) atomic weight

c.) atomic symbol

Which of the following is true of an isotope? a.) isotopes have the same number of neutrons but differ in the number of protons they contain b.) all isotopes of a given element are found in equal amounts in nature c.) isotopes have the same number of protons but differ in the number of neutrons they contain d.) isotopes exist only for a few elements

c.) isotopes have the same number of protons but differ in the number of neutrons they contain

Buffers __________. a.) build carbohydrates b.) serve as an energy source for a cell c.) stabilize pH d.) are strong acids

c.) stabilize pH

An ionic bond is __________. a.) a chemical bond in which two atoms equally share valence electrons b.) a chemical bond in which two atoms unequally share valence electrons c.) formed when a hydrogen atom already covalently linked to one electronegative atom binds with an electron-hungry atom of another molecule to form a "bridge" d.) a chemical bond formed by the transfer of one or more electrons from the valence shell of one atom to that of the other

d.) a chemical bond formed by the transfer of one or more electrons from the valence shell of one atom to that of the other

If the pH or temperature of the environment that contains a protein is altered dramatically, then the protein may __________. a.) become overly active b.) take on an α-helical structure c.) take on a quaternary structure d.) become denatured

d.) become denatured

Something with a pH of 5 would __________. a.) be described as being basic b.) have fewer H+ ions than OH- ions c.) be described as being neutral d.) have more H+ ions than OH- ions

d.) have more H+ ions than OH- ions