Biology Final Exam Fall 2022
You collect data on the effect of pH on the function of the enzyme catalase in human cells. Which of the following graphs would you expect?
)^(
During a laboratory experiment, you discover that an enzyme-catalyzed reaction has a ∆G of -20 kcal/mol. If you double the amount of enzyme in the reaction, what will be the ∆G for the new reaction?
-20kcal/ mol
sulfydryl group
-SH
Cellular respiration yields ______ ATP per molecule of glucose, which fermentation produces ______ molecules of ATP per glucose
30, 2
Based on your knowledge of the polarity of water molecules, the solute molecules depicted here is most likely _________. A) positively charged B) without charge C) negatively charged D) hydrophobic
A
In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by_______. A) polar covalent bonds B) hydrogen bond C) ionic bonds D) nonpolar covalent bonds
A
Water has a high specific heat because of the ______. A) hydrogen bond formed between hydrogen of one water, molecule, and the oxygen of another water molecule B) polar covalent bonds form between oxygen and hydrogen of a single water molecule C) ionic bonds formed between the hydrogen of one water molecule in the oxygen of another water molecule D) covalent bond formed between the hydrogen of one water, molecule, and the oxygen of another water molecule
A
What is the difference between covalent bonds and ionic bonds? A) covalent bonds involve the sharing of electrons between atoms; ionic bond involves the electrical attraction between charged atoms B) covalent bond involves the sharing of electrons between atoms, ionic bond involves the sharing of protons between charged atoms C) covalent bond involves the transfer of electrons between charged atoms, ionic bond involves the sharing of electrons between atoms D) covalent bonds involves the sharing of pairs of electrons between atoms, ionic bond involves the sharing of single electrons between atoms
A)
ATP is the cellular energy source used to carry out many different reactions. Explain why ATP is a good source of free energy and specifically how free energy from hydrolysis of ATP is used to power endergonic reactions in the cell
ATP provides the cell with a way to handle energy in an efficient manner. The molecule can be charged, stored, and used as needed. Moreover, the energy from hydrolyzing ATP is delivered as a consistent amount.
ATP binds to phosphofructokinase in a part of the enzyme that is not the active site, causing the enzyme to change shape and block substrate binding. ATP is functioning as an ________.
Allosteric inhibitor
which of the following is not directly synthesized from a DNA template?
Amino acids
Which of the following is true for this reaction? 3H2 + N2 both reversible arrow 2NH3 A) the reaction is nonreversible B) ammonia is being formed and decompose simultaneously C) hydrogen, and nitrogen are the products of the forward reaction D) hydrogen, and nitrogen are the reactants of the reverse reaction
B
The partial negative charge at one end of a water molecule is attracted to the partial positive charge of another water molecule. What is this attraction called? A) an ionic bond B) a covalent bond C) a hydrogen bond D) a hydrophilic bond
C
a solution with a pH of 5 has how many more protons, and then a solution with a pH of 7 A) 1000 times B) 10 times C) 100 times D) 5 times
C
the glucose molecule has a large quantity of energy in its _______.
C-H bonds
when propane (C3H8) and O2 react, CO2 and H2O are produced. This reaction is not normally reversible. Write and balance the chemical equation for this reaction are the products more or less ordered than the reactants? How do you know? do the products have a higher or lower potential energy than the reactants? How do you know? Is the reaction spontaneous or nonspontaneous?
C3H8 + 5O2 --> 3CO2 +4H2O Products are less ordered since the number of molecules increase the products have lower potential energy since H2O is polar the reaction is spontaneous
Which of the listed statements describes the results of the following reaction? C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
C6H12O6 is oxidized and O2 is reduced
carbonyl group
C=O
carboxyl group
COOH
A _________ inhibitor also binds to the active site of the enzyme
Competitive
An atom has four electrons in its valence shell. What types of covalent bonds is it capable of forming? A) single, and double only B) double bonds only C) single bonds only D) single double or triple
D
What results from the chemical reaction illustrated above? A) a cat ion with a net charge of negative one, and an anion with a net charge of positive one B) a cat ion with a net charge of positive one and an anion with a net charge of positive one C) a cat ion with a net charge of negative one and then an ion with a net charge of -1 D) a cat ion with a charge of positive one and an anion with a net charge of -1
D
Genotype is to _____ as phenotype is to _____.
DNA base sequence; physical traits that are products of the proteins produced
Dna vs Rna sugar: Nitrogenous base: Primary/ basic structure secondary structure
DNA: deoxyribose, T,A,G,C DOuble Stranded, Double Helix RNA: ribose, U,A,G,C, single stranded, stem loop
Complex II (succinate dehydrogenase)
FADH2 donates electron to this complex
Why is ATP an important molecule in metabolism?
It energetically couples exergonic and endergonic reactions.
What is the role of DNA ligase in the elongation of the lagging strand during DNA replication?
It joins Okazaki fragments together
Centriole
Microtubule organizing center
Energy released by the electron transport chain is used to pump H+ into which location in eukaryotic cells?
Mitochondrial inter-membrane space
Which organelle is the primary site of ATP synthesis in eukaryotic cells? Vacuole Mitochondrion Golgi Apparatus Lysosome
Mitochondrian
In the absence of oxygen , human muscle cells use lactic acid fermentation to oxide NADH to _____.
NAD+
amino group
NH2
hydroxyl group
OH-
Carbon Dioxide (CO2) is released during which of the following stages of cellular respiration
Oxidation of pyruvate to acetyl CoA and the ctiric acid cycle
Complex I (NADH dehydrogenase)
Oxidizes NADH to NAD+
phosphate group
PO4
Pyruvate dehydrogenase activity would be at its lowest when ________.
Pyruvate dehydrogenase is phosphorylated
in the process of transcription ________.
RNA is synthesized
Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids? Mitochondrion Ribosome Smooth Endoplasmic Reticulum Lysosome
Smooth Endoplasmic Reticulum
Where would you most likely find an integral membrane protein? Floating freely in the cytoplasm On the inside surface of the cell membrane On the outside surface of the cell membrane Spanning the cell membrane, with parts of the protein visible from both the inside and outside the cell
Spanning the cell membrane, with parts of the protein visible from both the inside and outside the cell
Which of the following structural features is common to cellulose, chitin, and peptidoglycan?
The can all form bonds between polymer chains that create parallel strands
How do the alpha and beta forms of glucose differ?
Their ring structures differ in the location of a hydroxyl group.
Which aspect of phospholipids is most important to the formation of bilayers? The length of their hydrocarbon tails can be altered to modulate membrane fluidity. They are amphipathic. Their polar heads can interact with water. Their hydrocarbon tails consist of fatty acids.
They are amphipathic.
Vesicle
Transport of secreted molecules and other proteins
Which organelle often takes up much of the volume of a plant cell? Vacuole Chloroplast Mitochondrion Lysosome
Vacuole
A peptide bond ______. a) forms the primary structure of proteins b) does not play a role in maintaining the tertiary structure of proteins c) forms between the central carbon and the amino R-group of a single amino acid d) forms between the functional R-groups of different amino acids
a
A series of enzyme's catalyze the reaction X->Y->Z->A. Product A binds to the enzyme that converts X to Y at a position remote from its active site. This binding decreases the activity of the enzyme. What does substance A function as? a. an allosteric inhibitor b. the substrate c. a competitive inhibitor d. an intermediate
a
A series of enzyme's catalyze the reaction X->Y->Z->A. Product A binds to the enzyme that converts X to Y at a position remote from its active site. This binding decreases the activity of the enzyme. What is substance X? a. a substrate b. an allosteric inhibitor c. the product d. an intermediate
a
At about pH 7 in most cells, what happens to the amino group on an amino acid? A) it acts as a base and gains a proton, giving it a positive charge B) it acts as an acid and loses a proton, giving it a negative charge C) it is reduced and tends to act as an electron donor in redox reactions D) it remains neutral, like water, and does not have a charge
a
At about pH 7 in most cells, what happens to the carboxyl group on an amino acid? A) it acts as an acid and loses a proton, giving it a negative charge B) it is oxidized and tends to act as an electron acceptor in redox reactions C) it acts as a base and gains a proton, giving it a positive charge D) it remains neutral, like water, and does not have a charge
a
Enzymes ________. a) increase the rate of a reaction by lowering the activation energy b) make the rate of a reaction independent of substrate concentrations c) increase the rate of a reaction by making the reaction more exergonic d) increase the rate of a reaction by reducing the rate of reverse reactions
a
From its atomic number of 15, it is possible to predict that the phosphorus atom has a) 15 protons and 15 electrons b) 8 electrons in its outermost shell c) 15 neutrons and 15 protons d) 5 neutrons, 5 protons, and 5 electrons
a
In human and many other eukaryotic species cells, the nuclear membrane has to disappear to permit...? a. the attachment of microtubules to kineochores b. the disassemble of the nucleolus c. the splitting of the centrosomes d. cytokinesis
a
In the polymerization of DNA, a phosphodiester bond is formed between a phosphate group of the nucleotide being aded and ... of the last nucleotide in the polymer. a. the 3' end b. the 5' phosphate c. C6 d. a nitrogen from the nitrogen containing base
a
Nucleic acids have a definite polarity, or directionality. Stated another way, one end of the molecule is different from the other end. How are these ends described? a) one end has an unlinked 3' hydroxyl; the other end has an unlinked 5' phosphate b) one end has one phosphate group; the other end has two phosphate groups c) one end has a hydroxyl group on the 2 carbon; the other end has a hydrogen atom on the 2 carbons d) one end contains a nitrogenous base; the other end lacks it
a
Phosphofructokinase is an allosteric enzyme that catalyzes the conversion of fructose 6phosphate to fructose 1,6 biphosphate, an early step in glycolysis. In the presence of oxygen, an increase in the amount of ATP in a cell would be expected to...? a. inhibit the enzyme and thus slow the rates of glycolysis and the citric acid cycle b. activate the enzyme and thus slow the rate of glycolysis and the citric acid cycle c. inhibit the enzyme and thus increase the rates of glycolysis and the citric acid cycle d. activate the enzyme and thus increase the rates of glycolysis and the citric acid cycle
a
Put the following steps of DNA replication in chronological order. 1. Single stranded binding proteins attach to DNA strands 2. Hydrogen bonds between base pairs of antiparallel strands are broken 3. Primase binds to the site of orign 4. DNA polymerase binds to the template strand 5. An RNA primer is creased a. 2, 1, 3,5, 4 b. 3, 1, 2 , 4, 5 c. 1, 2, 3, 4, 5, d. 3, 2, 1, 5, 4
a
Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's _______. a) activation energy b) entropy c) endothermic level d) free -energy content
a
Refer to the figure. What bases will be added to the primer as DNA replication proceeds? The bases should appear in the new strand in the order that they will be added starting at the 3' end of the primer? a. AGACGAC b. TCTGCTG c. CAGCAGC d. GTCGTCT
a
Semiconservative replication involves a templete. What is the templete? a. one strand of the DNA molecule b. single stranded binding proteins c. DNA polymerase d. an RNA molecule
a
Starting with one molecule of glucose, the energy containing products of glycolysis are...? a. 2 NADH, 2 pyruvate, and 2 ATP b. 2 NAD+, 2 pyruvate, and 2 ATP c. 2 FADH2, @ pyruvate, and 4 ATP d. 6 CO2, 2 pyruvate, and 2 ATP
a
What conclusion could be drawn from Messelson and Stahl's DNA replication experiment after a single round of DNA replication? a. DNA replication is not conservative b. DNA replication is semi conservative c. DNA replication is either dispersive or conservative d. DNA replication is not dispersive
a
When nucleotides polymerize to form a nucleic acid _____. a) a covalent bond forms between the sugar of one nucleotide and the phosphate of a second b) hydrogen bonds form between the bases of two nucleotides c) a hydrogen bond forms between the sugar of one nucleotide and the phosphate of a second d) covalent bonds form between the bases of two nucleotides
a
Which of the following is the strongest evidence that protein structure and function are correlated? a) denatured (UNFOLDED) proteins do not function normally b) proteins function best at certain temperatures c) proteins have four distinct levels of structure and many functions d) enzymes tend to be globular in shape
a
Which of the following statements is representative of the second law of thermodynamics? a) cells require a constant input of energy to maintain their high level of organization b) conversion of energy from one form to another is always accompanied by some gain of free energy c) without an input of energy, organisms would tend toward decreasing entropy d) heat represents a form of energy that can be used by most organisms to do work.
a
Why are polymerization reactions endergonic? Polymerization reactions _____. a) reduce entropy b) release heat, making the reactant monomers move faster c) are at equilibrium d) release energy
a
which of the following are purine nitrogenous bases? a) guanine and adenine b) cytosine and guanine c) uracil and cytosine d) adenine and thymine
a
which of the following are pyrimidine nitrogenous bases? a) cytosine and uracil b) ribose and deoxyribose c) guanine and adenine d) adenine and thymine
a
which statement is true of the following reaction? C6H12O6 + 6O2 --> 6CO2 + 6H20 a) glucose carbons are oxidized to carbon dioxide b) glucose oxygens are oxidized to water c) glucose oxygens are oxidized to carbon dioxide d) glucose carbons are reduced to carbon dioxide
a
Which of the following crosses lipid bilayers the slowest? a sodium ion a small, polar molecule like water. A large, polar molecule like glucose. a small, non-polar molecule like oxygen
a sodium ion
the oxygen consumed during cellular respiration is involved directly in which process or event?
accepting electrons at the end of the electron transport chain
Lysosome
acid hydrolases break down molecules
A substrate binds to an enzyme at the ___, of the enzyme
active site
With respect to the enzyme that converts X to Y, substance A functions as
an allosteric inhibitor
About 25 of the 92 Natural elements are known to be essential to life. Which 4 of these 25 elements make up approximately 96 percent of living matter? a) Oxygen, hydrogen, calcium, nitrogen b) Carbon, hydrogen, nitrogen, oxygen c)Carbon, oxygen, nitrogen, calcium d) Carbon, oxygen, phosphorus, hydrogen
b
Cellulose is _____. a) a storage polysaccharide for energy in plant cells b) a major structural component of plant cell walls c) used by plants to make glycogen d) a polymer composed of fructose monomers
b
Following the cell above through the cell cycle, which of the following would be observed at pro-metaphase of mitosis a. a b. b c. c d. d e. e
b
If a species is diploid and a certain gene found in the species has 18 known alleles (variants), then any given organism of that species can/must have which of the following? a. a haploid number of 9 chromosomes b. at most, 2 alleles for that gene c. up to 18 genes for that trait d. up to 18 chromosomes with that gene
b
Kinetochore microtubules assist in the process of splitting centromeres by _____. a. phosphorylating the centromere, thereby changing its conformation b. creating tension by pulling toward opposite poles c. sliding past each other like actin filaments d. using motor proteins to split th centromere at specific arginine residues
b
Lipids _______. a) are made by dehydration reactions b) are insoluble in water c) contain less energy than proteins and carbohydrates d) are made from glycerol, fatty acids, and nitrogen
b
Phospholipids and triglycerides both _____. a) have a phosphate b) have a glycerol backbone c) contain serine or some other organic compound d) have three fatty acids
b
What component of amino acid structure varies among different amino acids? a) the long carbon-hydrogen tails of the molecule b) the components of the R-group c) the presence of a central C atom d) the glycerol molecule that forms the backbone of the amino acid
b
What feature of single nucleotides provides the energy needed for polymerization when nucleic acids are formed? a) their sugar groups b) their phosphate groups c) their nitrogenous bases d) their methyl groups
b
When the atoms involved in a covalent bond have the same electronegativity, what type of bond results? a) an ionic bond b) a non-polar covalent bond c) polar covalent bond d) a hydrogen bond
b
Which cytoskeletal proteins are important constituents of the contractile structures that form the cleavage furrows involved in animal cell cytokinesis? a. Tubulin b. Actin c. Dynesin d. Myosin
b
Which of the following always tends to make chemical reactions spontaneous ? a) the reactants have lower potential energy than the products b) the reactants are more ordered than the products c) the temperature is low d) the pressure is low
b
Which of the following does NOT occur during mitosis? a. separation of the spindle poles b.replication of the DNA c. separation of the sister chromatids d. condensation of the chromosomes e. spindle formation
b
Which term most precisely descries the cellular process of breaking down large molecules into smaller ones? a. anabolism b. catabolism c. metabolism d. dehydration
b
Who preformed classic experiments that supported the semiconservative model of DNA replication? a. Franklin and Wilkins b. Meselson and Stahl c. Hershey and Chase d. Watson and Crick
b
You make a phospholipid bilayer with short, saturated hydrocarbon tails. You measure the permeability of this membrane to oxygen. You then double the length of the hydrocarbon tails and remeasure membrane permeability. You then double the length of the hydrocarbon tails again and make a third measurement of membrane permeability. You graph membrane permeability as a function of hydrocarbon tail length. Which of the accompanying graphs best represents the data you expect? a) _)^( b) \ c) / d) ---
b
side chains of amino acids a) are all non-polar b) may be polar or non-polar c) are non-polar if they contain N or S d) are all polar
b
the lock and key analogy for enzymes applies to the specificity of enzymes _____.
binding to their substrate
A cell begins G1 phase with 6 unreplicated chromosomes. This cell undergoes S, G2, and M phases. How many chromosomes will the daughter cells contain? a, 12 b. 3 c.6 d. 18
c
A covalent bond is likely to be polar when _____. a) the two atoms sharing electrons are the same elements b) carbon is one of the two atoms sharing electrons c) one of the atoms sharing electrons is more electronegative than the other atom d) the two atoms sharing electrons are equally electronegative
c
Bonds between two atoms that are equally electronegative are _____. a) hydrogen bonds b) polar covalent bonds c) non-polar covalent bonds d) ionic bonds
c
Carbon-12 is the most common isotope of carbon and has a mass number of 12. However, the average atomic mass of carbon found on a periodic table is slightly more than 12 daltons. Why? a) some carbon atoms in nature have a different valence electron distribution b) some carbon atoms in nature have an extra proton c) some carbon atoms in nature have more neutrons d) the atomic mass does not include the mass of electrons
c
Crossing over normally takes place during which of the following processes? a. Meiosis II b. Mitosis c. Meiosis I b. Mitosis and Meiosis II
c
DNA contains the template needed to copy itself, but it has no catalytic activity in cells. What catalyzes the formation of phosphodiester bonds between adjacent nucleotides in the DNA polymer being formed? a. Riboenzymes b. ATP c. DNA polymerase d. Deoxiribonucleotide triphosphates
c
Elements found on the left side of the periodic table, contain outer shells that are_______; these elements tend to form_______ in solution. A) almost empty; anions B) almost full; anions C) almost empty; cations D) almost full; cations
c
In trying to determine whether DNA or a protein is the genetic material, Hershey and Chase made use of which of the following facts? a. DNA contains nitrogen, whereas protein does not b. RNA includes ribose, whereas DNA includes deoxyribose sugars c. DNA contains phosphorus, whereas proteins do not d. DNA contains sulfur, whereas proteins do not
c
Lipids that contain a high number of double bonds in their fatty acid chains will ________. a) contain more hydrogens than lipids that contain few double bonds in their fatty acid chains b) pack very tightly together at room temperature c) likely be liquid at room temperature d) have a higher melting temperature than lipids that contain few double bonds in their fatty acid chains
c
Mendel studied seven different traits in the garden pea. What genetic term is used to describe an observable trait, such as those studied by Mendel? a. haplotype b. genotype c. phenotype d. category
c
Of the following, which os the most current description of a gene? a. A discrete unit of heredity information that consistes of a sequence of amino acids b. a DNA subunit that codes for single complete protein c. a DNA sequence that i expressed to form a functions; product: either RNA or a polypeptide d. A unit of heredity that causes formation of phenotypic characteristics
c
Suppose you discovered a new amino acid. Its R-group contains only hydrogen and carbon atoms. Predict the behavior of this amino acid. a) it is basic b) it is acidic c) it is non-polar d) it is polar
c
The bonding of two amino acids molecules to form a larger molecule requires the ______. a) addition of a water molecule b) addition of a carbon dioxide molecule c) release of a water molecule d) release of a carbon dioxide molecule
c
The microtubule organizing center found in animal cells is an identifiable structure present during all phases of the cell cycle. Specifically, it is known as the...? a. centromere b. microtubulere c. centrosome d. kinetochore
c
There are 20 different amino acids. What makes one amino acid different from another? a) different side chains (R-groups) attached to the amino groups b) different side chains (R-groups) attached to a carboxyl group c) different side chains (R-groups) attached to an alpha carbon d) different asymmetric carbons
c
What is/are the variable structure(s) of a nucleotide? a) the sugar b) the base c) the sugar and the base d) the phosphate group
c
What type of interaction is directly responsible for the formation of secondary structure? a) hydrogen bonds between side chains of amino acids b) peptide bonds between adjacent amino acids c) hydrogen bonds between sections of the polypeptide backbone d) peptide bonds between nonadjacent amino acids
c
Which drawing in the figure above depicts an atom with six valence electrons
c
Which process in eukaryotic cells will process normally whether oxygen is present or absent? a. the citric acid cycle b. electron transport c. glycolysis d. oxidative phosphorylation
c
Which two functional groups are always found in amino acids? a) ketone and methyl groups b) hydroxyl and carboxyl groups c) carboxyl and amino groups d) carbonyl and amino groups
c
Why did the F1 offspring of Mendel's classic pea cross always look like one of the two parental varieties? a. each allele affected phenptypic expression b. no genes interacted to produce the parental phenotype c. one allele was dominant c. the traits blended together during fertilization
c
Why is each element unique with respect to its chemical properties? Each element has a distinctive _____. a) number of neutrons b) atomic mass c) number of protons d) number of electrons
c
a chemical reaction that has a positive ∆G is best described as _______. a) spontaneous b) enthalpic c) endergonic d) exergonic
c
refer to the accompanying figure to answer the following questions H-N-C-C-N-C-C-O-H ^ ^. ^. ^. ^ A. B. C. D. E. Which bond is the peptide bond? a) A b) B. c) C. d) D. e) E.
c
the mathematical expression for the change in free energy of a system is ∆G=∆H-T∆S. Which of the following is correct? a) ∆H is change in entropy, the energy available to do work b) T is the temperature in degrees celsius c) ∆G is the change in free energy d) ∆S is the change in enthalpy, a measure of randomness
c
why is atp an important energy molecule in the cell? a) it is one of the four building blocks for DNA synthesis b) its hydrolysis provides an input of free energy for exergonic reactions c) it energetically couples exergonic and endergonic reactions d) its terminal phosphate bond has higher energy than the other two phosphate bonds
c
Cytochrome C
carries electrons from complex III to complex IV
anabolic pathways
consume energy to build up polymers from monomers
A covalent chemical bond is one in which _______. a) protons and neutrons are shared by two atoms so as to satisfy the requirements of both atoms b) outer-shell electrons of one atom are transferred to fill the inner electron shell of another atom c) electrons are removed from one atom and transferred to another atom so that the two atoms become oppositely charged d) outer-shell electrons of two atoms are shared so as to satisfactorily fill their respective orbitals
d
A solution of pH 4 has how many more protons in it than a solution with a pH of 7? a) 100 times b) 5 times c) 10 times d) 1000 times
d
An allosteric inhibitor decreases the rate of an enzyme reaction by...? a, binding at the active site of the enzyme b. changing the overall free energy of the reaction c. decreasing the activation energy of the reaction d. changing the shape of the enzymes active site
d
Choose the correct sequence of numbers to fill in the blanks to balance this equation. N2 + H2 -> NH3 a) 1,1,-1 b)1,3,1 c)1,2,2 d)1,3,2
d
For the duration of meiosis I, each chromosome _____. a. consistis of a single strand of DNA b. is paired with a homologous chromosome c. is joined with its homologous pair to form a synaptonemal complex d. consists of two sister chromatids joined by a centromere
d
If meiosis produces haploid cells, how is the diploid number restored for those organisms that spend most of their life cycle in the diploid state? a. DNA replication b. synapsis c. reverse transcription d.fertilization
d
If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence ________. a) 3' UAACGU 5' b) 5' TAACGT 3' c) 5' UGCAAU 3' d) 3' TAACGT 5'
d
In glycolysis, for each molecule of glucose oxidized to pyruvate...? a. two molecules of ATP are used and two molecules pf ATP are produced b. two molecules of ATP are used and six molecules of ATP are produced c. four molecules of ATP are used and two molecules of ATP are produced d. two molecules of ATP are used and four molecules of ATP are produced
d
In meiosis, homologous chromosomes are seperated during...? a. anaphase II b. telophase II c. prophase I d. anaphase I
d
Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? a) Nucleic acids b) Cellulose c) Lipids d) Proteins
d
Lipids that form membranes have what kind of structure? a) polar heads and non-polar tails; the non-polar tails interact with water b) polar heads and polar tails, which allows them to interact with water c) completely polar, which allows them to dissolve in water d) polar heads and non-polar tails; the polar heads interact with water
d
Mitosis separates chromosomes. Cytoplasm is divided between two daughter cells by _____. a. the formation of kinetochores b. binary fission c. cloning d. cytokinesis
d
Nitrogen (N) is more electronegative than hydrogen (H). Which of the following is a correct statement about the atoms in ammonia (NH3)? a) ammonia has an overall positive charge b) ammonia has an overall negative charge c) the nitrogen atom has a partial positive charge; each hydrogen atoms has a partial negative charge d) each hydrogen atom has a partial positive charge; the nitrogen atom has a partial positive charge
d
Sister chromatids separate from eachother during ...? a. meiosis I only b. mitosis only c. meiosis II only d. mitosis and mesiois II
d
The egg of a fruit fly has 4 individual chromosomes. How many chromosomes are in a somatic cell of a fruit fly? a. 2 b. 4 c. 16 d. 8
d
The first gap in the cell cycle (G1) corresponds to...? a. the phase in which DNA is being replicated b. the phase between DNA replication and the M phase c. the beginning of mitosis d. normal growth and cell function
d
The tertiary structure of a protein is the _______. a) order in which amino acids are joined in a polypeptide chain b) bonding together of several polypeptide chains by weak bonds c) organization of a polypeptide chain into an alpha helix or beta pleated sheet d) unique three-dimensional shape of fully folded polypeptide
d
Which of the following can vary among monosaccharides? a) the presence of a carbonyl group b) the presence of sulfur groups c) the presence of hydroxyl groups d) the number of carbon atoms
d
Which of the following is TRUE when comparing an uncatalyzed reaction to the same reaction with a catalyst? a) the catalyzed reaction will be slower b) the catalyzed reaction will have higher activation energy c) the catalyzed reaction will consume all of the catalyst d) the catalyzed reaction will have the same ∆G
d
Which of the following is an example of a reciprocal cross? a. An F1 is crossed back to one of its parents b. An individual with unknown genotype is crossed to a homozygous recessive individual c, two randomly chosen F2 individuals are crossed d, a mothers phenotype is an initial cross is the fathers phenotype in a subsequent cross and father's phenotype in the first cross is the mothers phenotype in the subsequent cross
d
Which of the following is an example of potential rather than kinetic energy? a) water rushing over Niagara falls b) the muscle contractions of a person mowing grass c) a crawling beetle foraging for food d) a molecule of glucose
d
Which of the following linkages would you expect to find at a branch point in glycogen or amylopectin? a) Beta-1,6-glycosidic linkage b) Alpha-1,4-glycosidic linkage c) Beta-1,4-glycosidic linkage d) Alpha-1,6-glycosidic linkage
d
Which of the following statements about NAD+ is TRUE? a. NAD+ can donate for use in oxidative phosphorylation b. NAD+ has more chemical energy than NADH c. NAD+ is oxidized by the action of hydrogenases d. NAD+ is reduced to NADH during glycolysis, pyruvate oxidation, and the citric acid cycle
d
Which process does not occur within a mitochondria in eukaryotic cells? a. Electron transport and oxidative phosphorylation b. pyruvate processing c. citric acid cycle d. glycolysis
d
homologous chromosomes...? a. carry the same alleles b. are identical c. align on the metaphase plate in meiosis II d. carry information for the same traits
d
the difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA _______. a) is in the alpha configuration and the sugar in RNA is in the beta configuration b) can form a double-stranded molecule c) is a six-carbon sugar and the sugar in RNA is a five-carbon sugar d) contains one less oxygen atom
d
the leading and lagging strand differ in that _______. a. the leading strand is synthesized by adding nucleotides to the 3' end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5' end b. the leading strand is synthesized at twice the rate of the lagging strand c. the lagging strand is synthesized continuously, whereas the leading strand is synthesized in short fragments that are ultimately stitched together d. the leading strand is synthesized in the same direction as the movement of replication fork, and the lagging strand is synthesized in the opposite direction
d
which of the following will increase the rate of a chemical reaction? a) decrease the amount of time in which the reaction is allowed to occur b) decrease the concentrations of the reactants c) decrease the temperature at which the reaction occurs d) Increase the temperature at which the reaction occurs
d
Complex IV (cytochrome c oxidase)
donates electrons to oxygen to form water
E. coli cells grown on 15N medium are transferred to 14N medium and allowed to grow for two more generations (two rounds of DNA replication). DNA extracted from these cells is centrifuged. What density distribution of DNA would you expect in this experiment? a. One low density band b. One high density band and one intermediate density band c. One high density and one low density band d. One intermediate density band e. One low density and one intermediate density band
e
Knowing the atomic mass of an element allows inferences about which of the following? a) the number of neutrons in the element b) the number of protons in the element c) the number of electrons present d) the number of protons plus electrons in the element e) the number of protons plus neutrons in the element
e
You have discovered an enzyme that can catalyze two different chemical reactions. Which of the following is most likely to be correct?
either the enzyme has two distinct active sites or the reactants involved in the two reactions are very similar in size and shape
FADH2
electron carrier that donates electrons to complex II
which of the following is a statement of the first law of thermodynamics?
energy cannot be created or destroyed
___________ is the type of regulation used in Glycolysis, Pyruvate Oxidation and the citric acid cycle
feedback inhibition
The mechanism in which the end product of a metabolic pathway inhibits an earlier step in the pathway is most precisely described as
feedback inhibiton
which process does not occur with a mitochondrian in a eukaryotic cell
glycolysis
nucleus
houses DNA
which of the following will increase the rate of a chemical reaction
increase the temperature at which the reaction occurs
Celery stalks that are immersed in freshwater for several hours become stiff. Similar stalks left in a 0.15 M salt solution become limp. From this, we can deduce that the freshwater ________. and the salt solution are both hypotonic to the cells of the celery stalks is hypertonic and the salt solution is hypotonic to the cells of the celery stalks is hypotonic and the salt solution is hypertonic to the cells of the celery stalks and the salt solution are both hypertonic to the cells of the celery stalks
is hypotonic and the salt solution is hypertonic to the cells of the celery stalks
When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?
it is lost to the environment
Why is glycolysis described as having an investment phase and a payoff phase?
it uses stored ATP and then forms a net increase in ATP
Smooth ER
lipid synthesis
Glycolysis is active when cellular energy levels are _____; the regulatory enzyme, phosphofructokinase, is _____ by ATP.
low; inhibited
Ribosome
macromolecular machine that produces prote
cell wall
made of cellulose in plants and peptidoglycan in bacteria
what does it mean when we say the genetic code is redundant?
more than one codon can specify the addition of the same amino acid
Complex III (cytochrome c reductase)
oxidizes ubiquinone and reduces cytochrome c
plasma membrane
phospholipid bilayer studded with proteins that serves as selective barrier
Chloroplast
photosynthesis
Mitochondria
produces ATP
Rough ER
produces proteins that will be transported to the plasma membrane
Peroxisomes
redox center of the cell
NADH
reduced in glycolysis, pyruvate processing and the citric acid cycle
Which of the following help(s) to hold the DNA strands apart while they are being replicated?
single-strand DNA binding proteins
Golgi apparatus
sorts and packages proteins and lipids
Vacuole
stores water and ions to maintain cell shape
Cytoskeleton
structure, support, and cell movement
catabolic pathways
supply energy, primarily in the form of ATP, for the cell's work
which of the following events takes place in the electron transport chain
the extraction of energy from high energy electrons remaining from glycolysis and citric acid cycle
In a bacterium, we will find DNA in ________. the nucleoid mitochondria a membrane-enclosed nucleus the endoplasmic reticulum
the nucleoid
which of the following statements is TRUE about enzyme catalyzed reactions?
the reaction is faster than the same reaction in the absence of the enzyme
which of the following is true for all exergonic reactions?
the reaction proceeds with a net release of free energy
the energy of electron transport serves to move (translocate) protons to the outer mitochondrial compartment how does this help the mitochonndrian produce ATP?
the translocation of protons sets up the electrochemical gradient that drives ATP synthesis in the mitochondria
Ions diffuse across membranes through specific ion channels down ______ their concentration gradients their electrochemical gradient their electrical (charge) gradient their chemical gradient
their electrochemical gradient
Why are fermentation reactions important for cells?
they regenerate NAD+ so that glycolysis can continue to operate
Ubiquinone
travels to complex III with electrons from complex I and II
