Download Exam I Review - Iowa State University

Biology II:
Exam I Review
Supplemental Instruction
Iowa State University
Leader:
Course:
Instructor:
Date:
Safwan Elkhatib
BIO 212 (6)
Coffman & Manz
Jan. 28, 2014
The molecule shown here is a
a. polysaccharide.
b. phospholipid.
c. saturated fatty acid.
*d. unsaturated fatty acid.
e. triglyceride (triacylglycerol).
Which of the following types of molecules are the major structural components of the cell membrane?
a. phospholipids and cellulose
*b. phospholipids and proteins
c. proteins and cellulose
d. nucleic acids and cholesterol
e. nucleic acids and proteins
All of the following molecules are part of the animal cell membrane except
a. polypeptides
*b. nucleic acids
c. sugars
d. phosphate groups
e. steroids
The organelle most directly involved in the synthesis of proteins is
*a. ribosome-studded rough endoplasmic reticulum.
b. lysosomes
c. smooth endoplasmic reticulum
d. Golgi apparatus
e. contractile vacuoles
Which of the following is true of both starch and cellulose?
*a. They are both polymers of glucose.
b. They can both be digested by humans.
c. They are both used for energy storage in plants.
d. They are both structural components of the plant cell wall.
The molecular formula C10H14O7N5P is for a biomolecule that can be described as a
a. Carbohydrate
*b. Nucleic Acid
c. Fatty Acid
d. Amino Acid
The molecular formula C18H32O2 is for a biomolecule that can be described as a
a. Carbohydrate
b. Nucleic Acid
*c. Fatty Acid
d. Amino Acid
1060 Hixson-Lied Student Success Center v 515-294-6624 v [email protected] v http://www.si.iastate.edu
Table salt (NaCl) is an example of what type of bonding
a. Hydrogen bonding
*b. Ionic bonding
c. Covalent bonding
d. Hydrophobic interactions
In a single molecule of water, two hydrogen atoms are bonded to an oxygen atom by
a. hydrogen bonds.
b. nonpolar covalent bonds.
*c. polar covalent bonds.
Atoms form covalent bonds with each other by:
a. transferring electrons from one atom to the other.
*b. sharing electrons.
c. sharing protons.
d. attraction of positive and negative charges.
e. sharing neutrons.
Which of the following is an INCORRECT statement?
a. Carbon bonds are stable at the different temperatures associated with life
b. Organic compounds may contain functional groups
c. Organic molecules may occur in various shapes. The structure of molecules determine their functions
*d. Organic chemistry is the science of studying Hydrogen containing molecules, which are found in living
organisms
Which is true of the base pairing seen between two DNA strands?
a. Cytosine bonds with adenine.
b. Guanine bonds with thymine.
c. Cytosine bonds with thymine.
*d. Thymine bonds with adenine.
e. Adenine bonds with guanine.
Which of the following is true when comparing solutions with a pH of 4 and a pH of 8?
a. The solution with a pH of 8 has a 4 times higher concentration of hydrogen ions than a solution with a pH of 4.
b. The solution with a pH of 8 has 10,000 times higher concentration of hydrogen ions than a solution with a pH of
4.
c. The solution with a pH of 8 has a 4 times lower concentration of hydrogen ions than a solution with a pH of 4.
*d. The solution with a pH of 8 has 10,000 times lower concentration of hydrogen ions than a solution with a pH of
4.
e. The hydrogen ion concentration does not appreciably differ between a solution with a pH of 8 versus that with a
pH of 4.
Which type of bond must be broken for water to vaporize?
a. ionic bonds
b. nonpolar covalent bonds
c. polar covalent bonds
*d. hydrogen bonds
Which of the following can cross the membrane unfacilitated?
a. Na+
b. ATP
*c. O2
d. Methionine (an amino acid)
A function of cholesterol that does not harm health is its role
a. in calcium and phosphate metabolism.
*b. as a component of cell membranes.
c. as the primary female sex hormone.
d. as the primary male sex hormone.
e. None of the above; all of cholesterol's effects on the body are harmful.
One way that winter wheat (and many other organisms) keep cell membranes fluid when environmental
temperatures drop in fall and winter is by
*a. increasing the percentage of unsaturated phospholipids in the membrane.
b. decreasing the number of hydrophobic proteins in the membrane.
c. increasing the percentage of saturated phospholipids in the membrane.
d. A and B are both correct.
A function of mitochondria in plant cells is
*a. to catabolize organic molecules converting that energy into ATP.
b. to capture photons and convert that energy into organic molecules.
c. help traffic proteins to the plasma membrane.
d. nothing. Plants don’t have mitochondria.
A function of the nucleus in a prokaryotic bacterium is
a. to house the genetic material for the cell.
b. to serve as the site of translation (protein synthesis).
c. to serve as the site of transcription (the making of RNA fromDNA).
*d. nothing. There is no nucleus in a bacterium.
e. both A and C are correct.
The selective permeability of biological membranes is dependent on which of the following?
a. the type of transport and channel proteins that are present in the membrane.
b. the lipid bilayer being permeable to small, nonpolar molecules; and impermeable to large or polar molecules.
c. the types of carbohydrates on the surface of the membrane.
*d. A and B only are correct.
Which types of transport can move substance from low concentrations to high concentrations?
a. diffusion
b. channel proteins
*c. active transport
d. facilitated diffusion
What type of transport protein can move 2 or more different molecules in opposite directions?
a. Uniporter
*b. Antiporter
c. Symporter
d. Multiporter
e. Diporter
In the formation of salt, the chlorine atom–
*a. Gains an electron from sodium
b. Becomes a positive ion
c. Has one more proton than electron
d. A and B are correct
e. A, B and C are correct
What characteristic(s) is/are likely to make a molecule soluble in water?
a. Small size
b. Nonpolar functional groups
c. Long hydrocarbon tails
*d. An ability to form hydrogen bonds
e. Choices A and C are both correct
73. Which of the following is FALSE?
a. Enzyme catalysis is dependent on the pH and temperature of the reaction environment.
b. Enzyme catalysis is dependent on the three-dimensional structure or conformation of the enzyme.
*c. Enzymes provide activation energy for the reaction they catalyze.
d. Enzyme activity can be inhibited by a molecule that binds to the enzyme far from the active site.
Hemoglobin is a tetramer, composed of four polypeptide subunits. When one of the subunits binds an oxygen
molecule, the affinity for oxygen of other subunits increases, so additional oxygen uptake becomes more
likely. This is best described as the result of:
a. enzyme saturation
b. allosteric inhibition
*c. allosteric activation
d. oxidative damage
If all of the molecules of an enzyme are saturated with substrate, the most effective way to obtain a faster
yield of products (increase the reaction rate) is to
*a. add more of the enzyme.
b. heat the solution to 90°C.
c. add more substrate.
d. add an allosteric inhibitor.
140. In exergonic reactions, like the oxidation of glucose,
a. the end products have more total energy than the starting reactants.
*b. there is a net release of free energy.
c. a net input of energy from the surroundings must occur.
d. the reaction cannot proceed without enzymes that lower the activation energy.
145. ATP is produced by _______ , ________ reactions and is used to drive ________, ________ reactions.
What words filled in these four spaces (in order) result in a true statement?
*a. endergonic, catabolic exergonic, anabolic
b. exergonic, anabolic endergonic, catabolic,
c. exergonic, catabolic endergonic, anabolic
d. endergonic, anabolic exergonic, catabolic
157. Most of the ATP made during cellular respiration is produced by
a. glycolysis.
*b. oxidative phosphorylation.
c. substrate level phosphorylations.
d. direct synthesis of ATP by the tricarboxylic acid cycle.
161. Which of the following statements about NAD+ is FALSE?
a. NAD+ is reduced to NADH during both glycolysis and the citric acid cycle.
*b. NAD+ has more chemical potential energy than NADH.
c. NAD+ can receive electrons for use in electron transport and oxidative phosphorylation.
d. In the absence of NAD+, glycolysis cannot proceed.
162. The ATP made during glycolysis is generated by
*a. transfer of phosphate from a phosphorylated carbon molecule to ADP, called substrate-level phosphorylation.
b. electron transport.
c. chemiosmosis.
d. oxidation of NADH to NAD+.
166. During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is
a. transferred to ADP, forming ATP.
b. transferred directly to ATP.
*c. retained in the pyruvate.
d. stored in the NADH produced.
169. Which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the
removal of a carbon (CO2) from one molecule of pyruvate?
a. glucose-6-phosphate
b. glyceraldehyde-3-phosphate
c. oxaloacetate
*d. Acetyl CoA
171. All of the following are products of the citric acid cycle EXCEPT
a. ATP.
b. NADH.
c. FADH2.
d. carbon dioxide.
*e. water
176. The oxygen consumed during cellular respiration is involved directly in which process or event?
a. glycolysis
*b. accepting electrons (and H+) at the end of the electron transport chain, forming water
c. the citric acid cycle
d. the oxidation of pyruvate to acetyl CoA
e. the phosphorylation of ADP to form ATP
187. As ATP levels in the cytoplasm of a cell increase, the rate of glycolysis is likely to
a. go up, because more ATP is available for the energy investment phase of glycolysis.
*b. go down, because elevated ATP results in feedback inhibition of phosphofructokinase (PFK).
c. remain unchanged, because the rate of glycolysis is controlled by the availability of oxygen.
d. slow, because NAD+ is used up