Biology 171 - Mideterm #1
Which of the following chemical formulas represents a carbohydrate? A. C12H22O11 B. CH4 C. C3H7O2N D. CO2
A. C12H22O11
If a DNA sample were composed of 10% thymine, what would be the percentage of guanine? A. 20 B. 40 C. 10 D. 80 E. impossible to tell from the information given
B. 40
What is ATP made from? A. adenosine + high energy electrons B. ADP + pyrophosphate C. AMP + ADP D. the conversion of guanine to adenosine
B. ADP + pyrophosphate
The hydrolysis of ATP to ADP and inorganic phosphate (ATP + H2O --> ADP + Pi) A. has a ΔG of about -7 kcal/mol under standard conditions. B. involves hydrolysis of a terminal phosphate bond of ATP. C. can occur spontaneously under appropriate conditions. D. Only A and B are correct. E. A, B and C are correct.
E. A, B and C are correct.
The sodium-potassium pump is an electrogenic pump because ___________. A. It moves three Na+ ions into the cell while removing two K+ ions out. B. It moves two K+ ions the cell while removing three Na+ ions out. C. It creates an electrical charge imbalance across the plasma membrane. D. A and C are correct. E. B and C are correct.
E. B and C are correct.
Which of these is found in all amino acids? A. -COOH B. -COH C. -OH D. -NH2 E. Both -COOH and -NH2
E. Both -COOH and -NH2
What are the two classifications of prokaryotes? A. domain Bacteria and domain Eukarya B. domain Archaea and kingdom Monera C. domain Eukarya and kingdom Monera D. domain Bacteria and kingdom Monera E. domain Bacteria and domain Archaea
E. domain Bacteria and domain Archaea
What is the pH of a solution with [H3O+] = 1/100000 M (10-5M)? A. pH= 1 B. pH= 2 C. pH= 3 D. pH= 4 E. pH= 5
E. pH= 5
Oxygen crosses a plasma membrane by A. osmosis. B. phagocytosis. C. active transport. D. pinocytosis. E. passive transport.
E. passive transport.
A polypeptide can best be described as a A. monomer of a protein polymer. B. polymer containing 20 amino acid molecules. C. polymer containing 19 peptide bonds. D. polymer containing 20 peptide bonds. E. polymer of amino acids.
E. polymer of amino acids.
Name and describe the functional groups.
amino, carbonyl/keto/ketone, carbonyl/aldehyde/aldo, methyl, phosphate, hydroxyl, sulfhydryl, carboxyl
Parts of the phospholipid bilayer
Glycoprotein, cholesterol, phospholipid, extracellular matrix, protein
n salt, the sodium ion is attracted to the chloride ion by a(n) ____ bond.
Iionic
Name parts of the chloroplast
Inner membrane, Outer membrane, Granum, Thylakoid membrane, DNA, Stroma
Atoms with same number of protons but different mass (weight) are known as
Isotopes
Parts of ribosome?
Large and small subunit
The shape of hair proteins is maintained by a combination of hydrogen bonds and covalent, disulfide bonds. Heat is sufficient to break the hydrogen bonds, but harsh chemicals are required to break the disulfide bonds. Why is it harder to break the disulfide bonds than the hydrogen bonds? A. Covalent bonds are stronger than hydrogen bonds. B. There are many more disulfide bonds than hydrogen bonds. C. Covalent bonds are stronger than disulfide bonds. D. Covalent bonds are less elastic than hydrogen bonds.
A. Covalent bonds are stronger than hydrogen bonds.
Which of the following would likely move across a plasma membrane most rapidly? A. O2 B. glucose C. K+ D. starch
A. O2
The word hydrolysis is defined as the lysis of water. How does this apply to polymers? A. Polymers break by separating water into hydrogen and hydroxyl group that are added to the monomers. B. Polymers are separated into monomers producing energy and water molecules. C. Polymers are synthesized by using the energy released by the breaking of water molecules into hydrogen and hydroxyl group. D. Polymers are hydrolyzed into monomers using water in the process and are called as dehydration synthesis.
A. Polymers break by separating water into hydrogen and hydroxyl group that are added to the monomers.
Colony collapse disorder (CCD) is unexplained loss of entire bee colonies that has been occurring in increased numbers across the world. The cause of the disorder is unknown, although it has been suggested that pesticides may play a role. To study this phenomenon, 300 bee colonies at 20 different sites across the U.S. are analyzed. Colonies are classified as having no CCD symptoms (group 1) or as having CCD symptoms (group 2). Bee pollen is isolated from group 1 and group 2 colonies and analyzed for the presence of pesticides. What is the control group in this study? A. The control group is group 1 (colonies with no CCD symptoms) B. The control group is group 2 (colonies having CCD symptoms) C. This study should have a control group but lacks one. D. This study doesn't need a control group.
A. The control group is group 1 (colonies with no CCD symptoms)
Which of the following is true of geometric isomers? A. They have variations in arrangement around a double bond. B. They have an asymmetric carbon that makes them mirror images. C. They have the same chemical properties. D. They have different molecular formulas. E. Their atoms and bonds are arranged in different sequences.
A. They have variations in arrangement around a double bond.
In a hydrolysis reaction, _____, and in this process water is _____. A. a polymer is broken up into its constituent monomers ... consumed B. a monomer is broken up into its constituent polymers ... produced C. monomers are assembled to produce a polymer ... consumed D. monomers are assembled to produce a polymer ... producedE.a polymer is broken up into its constituent monomers ... produced
A. a polymer is broken up into its constituent monomers ... consumed
The synthesis of sucrose is an example of a(n) ____process. A. anabolic B. catabolic C. hydrolysis D. transcription
A. anabolic
Which of the following are capable of converting light energy to chemical energy? A. chloroplasts B. mitochondria C. leucoplasts D. peroxisomes E. Golgi bodies
A. chloroplasts
Which of the following best defines the term organelle? A. compartment or sac within a cell B. cell that has a membrane-bound nucleus and several other membrane-bound compartments or sacs C. green pigment that captures the light energy that drives the light reactions of photosynthesis D. membrane-bound sac, somewhat larger than a vesicle, which functions in cellular storage and transport
A. compartment or sac within a cell
Which of the following adheres to the extracellular surface of animal cell plasma membranes? A. fibers of the extracellular matrix B. fibers of the cytoskeleton C. the phospholipid bilayer D. cholesterol E. carrier proteins
A. fibers of the extracellular matrix
Define the heat of vaporization of water A. high amount of energy required for liquid water to turn into water vapor B. the amount of heat one gram of a substance must absorb or lose to change its temperature by one degree Celsius C. amount of heat required to make hydrophobic substances dissolve in water D. Heat required to dissociate H2O into H+ and OH-
A. high amount of energy required for liquid water to turn into water vapor
A molecule that has all nonpolar covalent bonds would be _____. A. hydrophobic B. hydrophilic C. acidic D. basic (alkaline) E. ionic
A. hydrophobic
In a hypotonic solution an animal cell will A. lyse. B. experience turgor. C. neither gain nor lose water. D. shrivel. E. lose water.
A. lyse.
The four main categories of large biological molecules present in living systems are _____. A. proteins, nucleic acids, carbohydrates, and lipids B. monosaccharides, lipids, polysaccharides, and proteins C. proteins, DNA, RNA, and steroids D. nucleic acids, carbohydrates, monosaccharides, and proteins E. RNA, DNA, proteins, and carbohydrates
A. proteins, nucleic acids, carbohydrates, and lipids
The molecular mass of glucose (C6H12O6) is 180 g. To make a 0.5 M solution of glucose, you should do which of the following? A. Dissolve 0.5 g of glucose in a small volume of water, and then add more water until the total volume of solution is 1 L. B. Dissolve 90 g of glucose in a small volume of water, and then add more water until the total volume of the solution is 1 L. C. Dissolve 180 g of glucose in a small volume of water, and then add more water until the total volume of the solution is 1 L. D. Dissolve 0.5 g of glucose in 1 L of water. E.Dissolve 180 g of glucose in 1 L of water.
B. Dissolve 90 g of glucose in a small volume of water, and then add more water until the total volume of the solution is 1 L.
How do chemical reactions play a role in energy transfer? A. Energy from the breakdown of glucose and other molecules in animals is released in the form of NADP, which transfers energy to other reactions. B. Energy from the breakdown of glucose and other molecules in animals is released as ATP, which transfer energy to other reactions. C. Energy is released in the form of glucose from the breakdown of ATP molecules. These ATP molecules transfer energy from one reaction to other. D. Energy is released in the form of water from the breakdown of glucose. These molecules transfer energy from one reaction to other.
B. Energy from the breakdown of glucose and other molecules in animals is released as ATP, which transfer energy to other reactions.
Often secreted proteins are modified with sugar residues. Where would you expect the sugar residues to be added on to the protein? A. peroxisome B. Golgi apparatus C. smooth endoplasmic reticulum D. rough endoplasmic reticulum
B. Golgi apparatus
You are making a poster of a generic bacterium for your class. Which of the following structures will you leave out of your poster? A. Plasma membrane B. Nucleolus C. DNA D. Ribosome
B. Nucleolus
Read the following questions. Does the statement lend itself to investigation using the scientific method? In other words, is the hypothesis falsifiable (can be proven false)? Is macaroni and cheese tastier than broccoli soup? Are hummingbirds attracted to the color red? Is the moon made out of green cheese? Is plagiarism dishonest? A. Questions 3 and 4 are subjective and cannot be disproven using scientific method. Questions 1 and 2 can be tested using scientific method. B. Questions 1 and 4 are subjective and cannot be disproven using scientific method. Questions 2 and 3 can be tested using scientific method. C. Questions 1 and 3 are subjective and cannot be disproven using scientific method. Questions 2 and 4 can be tested using scientific method. D. Questions 1 and 2 are subjective and cannot be disproven using scientific method. Questions 3 and 4 can be tested using scientific method.
B. Questions 1 and 4 are subjective and cannot be disproven using scientific method. Questions 2 and 3 can be tested using scientific method.
If the pH outside the cell decreases, would you expect the amount of amino acids transported into the cell to increase or decrease? A. Transport of amino acids into the cell stops. B. Transport of amino acids into the cell increases C. Transport of amino acids into the cell is not affected by pH. D. Transport of amino acid into the cell decreases.
B. Transport of amino acids into the cell increases
An ionic bond involves _____. A. the sharing of a single pair of electrons B. an attraction between ions of opposite charge C. no atoms other than sodium and chlorine D. the unequal sharing of an electron pair E.water avoidance
B. an attraction between ions of opposite charge
The movement of potassium into an animal cell requires A. a gradient of protons across the plasma membrane. B. an energy source such as ATP or a proton gradient. C. low cellular concentrations of sodium. D. high cellular concentrations of potassium. E. a cotransport protein.
B. an energy source such as ATP or a proton gradient.
Lipids differ from other large biological molecules in that they _____. A. are much larger B. are not truly polymers C. do not have specific shapes D. do not contain carbon E. do not contain nitrogen and phosphorus atoms
B. are not truly polymers
According to the first law of thermodynamics, A. matter can be neither created nor destroyed. B. energy is conserved in all processes. C. all processes increase the order of the universe. D. systems rich in energy are intrinsically stable. E. the universe constantly loses energy because of friction.
B. energy is conserved in all processes.
Which membrane transport process matches with the primary function of that process? A. phagocytosis : secretion of large particles from the cell by fusion of vesicles with the plasma membrane. B. exocytosis : the movement of water and solutes into the cell by vesicle fusion with the plasma membrane. C. pinocytosis : the uptake of water and small solutes into the cell by formation of vesicles at the plasma membrane. D. osmosis : passive diffusion of water and dissolved ions and other solutes across a membrane. E. None of the above are correct matches.
B. exocytosis : the movement of water and solutes into the cell by vesicle fusion with the plasma membrane.
In salt, what is the nature of the bond between sodium and chlorine? A. nonpolar covalent B. ionic C. hydrogen D. hydrophobic E. polar covalent
B. ionic
In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? A. Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. B. Eukaryotic cells contain a nucleus. C. Compartmentalization of the cytoplasm by membrane-bounded organelles occurs in eukaryotic cells. D. Eukaryotic cells have a plasma membrane and prokaryotic cells do not. E. Eukaryotic cells are larger than prokaryotic cells.
C. Compartmentalization of the cytoplasm by membrane-bounded organelles occurs in eukaryotic cells.
How does the structure of a DNA molecule compare with that of an RNA molecule? A. DNA is single stranded, while RNA is a triple helix. B. DNA is a triple helix, while RNA is a double stranded molecule. C. DNA is a double stranded twisted ladder, while RNA is single stranded. D. DNA is circular in shape, while RNA is triple stranded.
C. DNA is a double stranded twisted ladder, while RNA is single stranded.
The reaction A --> B + C + heat is released in a(n) _____ reaction. A. endergonic B. dehydration synthesis C. exergonic D. exchange E. anabolic
C. exergonic
Denaturation is A. process through which messenger RNA forms on a template of DNA B. reaction that causes breakdown of larger molecules into smaller molecules with the utilization of water C. loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals D. process through which RNA directs the formation of protein
C. loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals
Hydrophobic molecules are _____ water. A. attracted to B. absorbed by C. repelled by D. neutralized by E. polarized by
C. repelled by
What is an active site? A. small organic molecule, such as a vitamin or its derivative, which is required to enhance the activity of an enzyme B. molecule on which the enzyme acts C. specific region of the enzyme to which the substrate binds D. bond that connects phosphates in an ATP molecule
C. specific region of the enzyme to which the substrate binds
What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons? A. 6 B. 8 C. +1 D. 12 E. 18
D. 12
Transport across membrane can be active or passive. Which figure represents active transport? A. Figure A B. Figure B C. Figure C D. Figure D E. Figure A and C
D. Figure D
Which of the following statements about the cytoskeleton is true? A. Intermediate filaments are used to separate replicated chromosomes during cell division. B. Flagella and pili have a similar structural arrangement of microtubules. C. Intermediate filaments are made of polymerized dimers of α-tubulin and β-tubulin. D. Microfilaments function in cellular movement.
D. Microfilaments function in cellular movement.
Which of the following functional groups are both commonly charged? A. Hydroxyl and methyl B. Sulfhydrl and hydroxyl C. Methyl and carbonyl D. Phosphate and carboxyl E. Carbonyl and Carboxyl
D. Phosphate and carboxyl
Which of the following is an example of cooperativity? A. binding of an ATP molecule along with one of the substrate molecules in an active site B. the effect of increasing temperature on the rate of an enzymatic reaction C. the binding of an end product of a metabolic pathway to the first enzyme that acts in the pathway D. a molecule binding at one unit of a tetramer allowing faster binding at each of the other three E. protein function at one site affected by binding at another of its active sites
D. a molecule binding at one unit of a tetramer allowing faster binding at each of the other three
What results from an unequal sharing of electrons between atoms? A. a hydrophobic interaction B. a nonpolar covalent bond C. an ionic bond D. a polar covalent bond E. a hydrogen bond
D. a polar covalent bond
What is the measure of hydrogen ion concentration? A. Acid B. base C. buffer D. pH E. Micro moles
D. pH
Which of the following is a compartment that often takes up much of the volume of a plant cell? A. peroxisome B. mitochondrion C. Golgi apparatus D. vacuole E. lysosome
D. vacuole
Respiration is a catabolic process. True False
True
