Cell Bio Final
Which of the following channels would not be expected to generate a change in voltage by movement of its substrate across the membrane where it is found? a) a proton channel b) an aquaporin c) a calcium channel d) a sodium channel e) a potassium channel
an aquaporin
) Which of the following is NOT a protein that crosslinks different actin filaments or connects two actin filaments together: A) fimbrin B) cofilin C) α-actinin D) filamin E) the Arp 2/3 complex
cofilin
Which of the following is the largest? A) hyaluronan B) collagen C) decorin D) fibronectin E) connexin
hyaluronan
The evaporation of sweat, used by many mammals to cool their bodies, cools a body by removing a large amount of heat that is then used to break what kind of molecular interactions? a) ionic bonds. b) covalent bonds. c) hydrogen bonds. d) Van der Waals interactions e) peptide bonds.
hydrogen bonds
16) The Sec61 complex is responsible for which process? a) mitochondrial import b) Peroxisome import c) Glycosylation in the ER d) Transport to the golgi e) import into the ER
import into the ER
Which structure is normally found on the 5' end of a DNA strand?a) phosphate group b) sulfur group c) nitrogenous base d) hydroxyl group e) carboxyl group
phosphate group
36) Which type of lipid is the most abundant in the plasma membrane and in the mitochondrial membrane? a) phosphatidylcholine b) phosphatidylserine c) phosphatidylethanolamine d) phophatidyinositol e) triacylglycerides
phosphatidylcholine
59) Which of the following processes can depend on caveolin proteins: a) receptor-mediated endocytosis. b) phagocytosis. c) pinocytosis. d) exocytosis e) clathrin-mediated endocytosis
pinocytosis
Which of the following are activated carrier molecules that carry energy in the form of electrons coupled with hydrogen ions: a) carboxylated biotin b) NADH c) FADH2 d) ATP e) NADPH f) Acetyl CoA
NADH FADH2 NADPH
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). Their subunits bind ATP and hydrolyze it
actin filaments
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). These are very thin and bend easily.
actin filaments
Which types of filaments are at least moderately flexible? A) actin filaments only B) microtubules only C) intermediate filaments only D) microtubules and intermediate filaments E) actin filaments and intermediate filaments
actin filaments and intermediate filaments
14) The purpose for mannose elimination on the oligosacharride in the ER is for what purpose? a) binding to the COPII coat proteins. b) transport to the golgi from the ER. c) designating whether a protein is folded properly. d) acts as a clock that indicates that the protein needs to be degraded. e) designating whether a protein needs to be secreted outside the cell.
acts as a clock that indicates that the protein needs to be degraded
A signaling protein that is only made up of one SH2 domain and two SH3 domains is most likely a(n)____________. a) kinase associated with receptor tyrosine kinase signaling. b) a guanine nucleotide exchange factor. c) adaptor protein d) monomeric G protein. e) negative regulator of receptor tyrosine kinase signaling.
adaptor protein
You have developed a promising anti-cancer agent, but it has poor solubility in water. Which of the following changes would not increase water solubility?A. adding an amine group B. adding a hydroxyl group C. adding a methyl group D. adding a carboxyl group E. adding a carbonyl group
adding a methyl group
38) This type of receptor changes conformation in response to ligands to allow ions to move across the membrane. a) steroid transporterb) enzymatic receptorc) G protein-coupled receptord) adaptor receptor e) channel-linked receptor
channel-linked receptor
When bound to ligand, this type of receptor changes conformation to allow ions to move down their concentration gradient across the membrane. a) channel-linked receptor b) enzymatic receptor c) G protein-coupled receptor d) adaptor receptor e) steroid hormone receptor.
channel-linked receptor
Which of the following molecules is responsible for linking cortical actin filaments between two cells in adherens junctions? A) classical cadherins B) nonclassical cadherins C) integrins D) claudin E) occludin
classical cadherins
Which is responsible in part for forming a seal between cells (tight junctions) and a fence between plasma membrane domains? A) P-selectin B) claudin C) E-cadherin D) fibronectin E) vinculin
claudin
) Which if the following molecules have cryptic binding sites for further protein interactions when pulled on and unwound (i.e. they interact in different ways with each other or with other proteins)? A) hyaluronan and collagen B) fibronectin and α catenin C) decorin and hyaluronan D) desmoplakin and periecan E) claudin and occuludin
fibronectin and α catenin
How do chromosomes get to the center of the cell during metaphase? A) forces of kinesins 4 and 10 alone B) forces of Kinesin-5 alone C) forces of Dynein alone D) shortening of kinetochore microtubules alone E) forces of kinesins 4 and 10 in combination with shortening of kinetochore microtubules
forces of kinesins 4 and 10 in combination with shortening of kinetochore microtubules
Which of the following is the molecule(s) that is involved in creation of creation/stability of actin filaments in the cortical cytoskeleton? Some of these molecules have "whiskers) A) tropomysin B) profilin C) formin D) the Arp 2/3 complex E) thymosin
formin
Which of the following molecules is made up of the highest percentage of oxygen by weight: a) steroids b) glycogen c) amino acids d) triglycerides e) DNA
glycogen
Which of the following statements is true about various carbohydrate molecules: a) glycogen is soluble, cellulose in not soluble. b) glycogen is made in plants, starch is made in animals. c) starch is more highly branched than cellulose. d) glycogen and cellulose are made from the same kind of sugar. e) glycogen and cellulose are both completely linear polymers.
glycogen is soluble, cellulose in not soluble starch is more highly branched than cellulose glycogen and cellulose are made from the same kind of sugar
Secondary structure of a polypeptide is primarily maintained by: a) interaction of the N terminal amino and C terminal carboxyl charges. b) hydrophobicity of the side chain R groups. c) hydrogen bonding between the side chain R groups, such as serine and threonine. d) hydrogen bonding between the carbonyl groups and amino hydrogens of the peptide backbone(s). e) electrostatic interactions between charged amino acids.
hydrogen bonding between the carbonyl groups and amino hydrogens of the peptide backbone(s)
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). Their subunits bind GTP and hydrolyze it.
microtubules
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). They are hollow with multiple lateral interactions between subunits.
microtubules
In hot arid environments, what is the process that Rubisco mediates that is a problem that causes loss of energy to plants? A) photosynthesis B) photorespiration C) carboxylation D) oxygenesis E) dehydrogenation
photorespiration
ER Tail-anchored Proteins Are Integrated into the ER Membrane by: a) sec61 b) calnexin c) Pex 19 d) the Get ATPase and Get1/Get2 complex e) glucosyl tranferase
the Get ATPase and Get1/Get2 complex
The ADAR protein is known to mediate mRNA editing, converting adenine bases to inosines. What best explains how ADAR recognizes which Adenines to convert? a) the presence of an alternative 5' splice acceptor site b) the presence of an alternative 3' splice acceptor site c) the presence of antisense RNA d) the presence of a hairpin sequence. e) the presence of a cryptic polyadenylation site.
the presence of a hairpin sequence
What event costs 1 out of every protons that the electron transport chain pumps in mitochondria: a) powering the ATP/ADP translocase b) powering pyruvate translocation into mitochondria c) transporting inorganic phosphate into the matrix d) transporting O2 into the matrix e) transporting CO2 into the matrix
transporting inorganic phosphate into the matrix
Plastoquinone is structurally and functionally similar to which of the proteins in the mitochondrial electron-transport chain? a) Cytochrome c b) ubiquinone c) Succinate dehydrogenase (complex II) d) NADH e) Cytochrome c reductase (complex III)
ubiquinone
Which of the following molecules is responsible for recruiting additional actin filaments to a cadherin molecule when stressed? A) P-selectin B) vinculin C) fibronectin D) claudin E) occludin
vinculin
At the end of photosynthesis, where do the oxygen atoms that are in the O2 that is produced come from? A) CO2 B) RuBP C) Rubisco D) G3P E) Water
water
10) An individual transport vesicle ________. a) contains only one type of protein in its lumen. b) will carry a specific coat protein throughout its entire lifetime. c) will fuse with only one type of membrane. d) is endocytic if it is traveling from the Golgi. e) is enclosed by a membrane with the same lipid and protein composition as the membrane of the donor organelle.
will fuse with only one type of membrane
Using the Calvin Cycle, how many ATP and NADPH are used to create a glucose molecule? A) 9 ATP, 6 NADPH B) 6 ATP, 6 NADPH C) 12 ATP, 12 NADPH D) 12 ATP, 18 NADPH E) 18 ATP, 12 NADPH
18 ATP, 12 NADPH
29) A molecule inside the cytoplasm of a plant cell would have to pass how many lipid bilayers in order to enter the inside of thylakoid lumen (inside the thylakoid discs) of a chloroplast? a) 1 b) 2 c) 3 d) 4 e) 5
3
In the electron transport chain, how many large muliti-subunit complexes will a given electron be expected to pass through? A) 1 B) 2 C) 3 D) 4 E) 5
3
At physiological pH (approximately 7.1), what is the approximate net charge of a peptide with the following amino acid sequence? Lysine-Aspartate-Valine-Isoleucine-Glutamate -Serine-Glutamine-Arginine A. -2 B. -1 C. 0 D. +1 E. +2
0
) Supposing two enhancer sequences are in a promoter for a gene. Two activators, X and Y, bind to these two sequences respectively, with Y binding slightly tighter. Which of the following best represents the predicted ratio of transcription that occurs when comparing the relative transcription rates of the following cells? Ratio} cells with nuclear localization of X only: cells with nuclear localization of Y only: cells with nuclear localization of X and Y a) 3:2:1 b) 1:2:1 c) 1:2:3 d) 1:1:1 e) 1:2:100
1:2:100
How many reduced ferroredoxin does it take to create 1 NADPH? A) 1 B) 2 C) 3 D) 4 E) 5
2
How many reduced cytochrome c molecules does it take to pump protons in cytochrome c oxidase (complex IV)? A) 1 B) 2 C) 3 D) 4 E) 5
4
What are the products from (only) the Krebs cycle derived from 1 molecule of glucose? a) 1 CO2, 2 NADH, 1 FADH2, 1 ATP b) 2 CO2, 3 NADH, 1 FADH2, 1 ATP c) 4 CO2, 12 NADH, 4 FADH2, d) 4 ATP 4 CO2, 6 NADH, 2 FADH2, 4 ATP e) 4 CO2, 6 NADH, 2 FADH2, 2 ATP
4 CO2, 6 NADH, 2 FADH2, 2 ATP
Name the three main ways that an mRNA molecule is modified in eukaryotic cells that differs from mRNA in prokaryotic cells.
5' capping 3' polyadenylation splicing
The sequence of the coding strand of a DNA molecule (that is, the DNA strand that contains the codons specifying the protein sequence) is 5'-CGGATGCTTA-3'. What is the sequence of the RNA made from this DNA?a) 5'-UAAGCAUCCG-3' b) 5'-AUUCGUAGGC-3' c) 5'-GCCUACGAAU-3' d) 5'-CGGAUGCUUA-3' e) 5'-TAAGCATCCG-3'
5'-CGGAUGCUUA-3'
The multidrug resistance protein is a member of this family ABC transporter (A), a P-type pump (B), or a V-type pump (C).
ABC transporter
This family is the largest among membrane transport proteins ABC transporter (A), P-type pump (B), or a V-type pump (C).
ABC transporter
Activation of an amino acid by an aminoacyl-tRNA synthetase involves the covalent linkage of... a) ADP to the amino acid. b) AMP to the amino acid. c) phosphate to the amino acid. d)AMP to the tRNA. e) ADP to the tRNA.
AMP to the amino acid
Unlike a myosin head, a kinesin head is tightly bound to its cytoskeletal track when bound to ... A) GDP. B) GTP. C) ADP. D) ATP. E) no nucleotide.
ATP
Which of the following is not a molecule directly involved in the reaction processes of Fermentation? A) Acetaldehyde B) ATP C) NADH D) Lactate E) Ethanol
ATP
Which of the following is made during the light reactions of photosynthesis? a) ADP and NADP+ b) Glucose and ATP c) ATP and NADPH d) NADPH and Carbon Dioxide e) CO2 and H2O
ATP and NADPH
What is the main source of the free energy for the mechanical work performed by DNA helicases during DNA replication in our cells? A. The hydrogen-bonding energy in the DNA double helix B. Thermal energy in the nucleus C. ATP hydrolysis by the helicase D. The energy of SSB binding to single-stranded DNA E. ATP hydrolysis by DNA topoisomerases
ATP hydrolysis by the helicase
25) Lysosomes are the principal site of cellular digestion. They ... a) normally maintain a pH of about 5.0 to 5.5. b) contain V-type ATPases that pump protons into the organelles. c) contain heavily glycosylated membrane proteins on the inside of the lysosomal membrane. d) are seldom identical in size and shape. e) All of the above.
All of the above
What is the general term for biological pathways where smaller molecules are built into larger molecules?
Anabolic pathways
71) Which of the following organisms would have the highest amount of unsaturated fatty acids in its membranes? a) Desert iguana b) Polar bear c) Thermophilic bacteria d) Humans e) Antarctic fish
Antarctic fish
85) A transmembrane protein has the following properties: it has two binding sites, one for solute A and one for solute B. The protein can undergo a conformational change to switch between two states: Solute A may bind exclusively on one side of the membrane, or Solute B may bind exclusively on the other side of the membrane. The protein can switch between the two conformational states only if one binding site is occupied, but not if both binding sites are empty. What kind of a transporter do these properties define? ______________________
Antiporter
Dr. Morgan is trying to express a protein in his cancer cells that is activated by phosphorylation of a serine residue. He proposed making a mutation in the protein of the Serine to a different amino acid that would mimic phosphorylation and make the protein active all of the time, instead of only when it was phosphorylated. What two amino acids would be the best choices for doctor Morgan to use?
Aspartate and Glutamate
Which of the following is where a signaling molecule is released from cell and then binds a receptor on the same cell? a) Juxtacrine Signaling b) Paracrine Signaling c) Autocrine Signaling d) Synaptic Signaling e) Endocrine Signaling
Autocrine Signaling
Which of the following is NOT a substrate of caspases as mentioned in class lecture slides? A) caspase-3 B) PARP C) ICAD D) BCL-2 E) RIPK1 (RIP1)
BCL-2
Which of the following proteins is thought to form pores in the mitochondria? A) Bim B) Bax C) Bcl-2 D) Bid E) Bcl-xL
Bax
What roles in regulating the intrinsic pathway of apoptosis are played by the Bcl-2 protein family members Bax and Bcl-2? A) Bax stimulates apoptosis while Bcl-2 inhibits apoptosis. B) Both Bax and Bcl-2 inhibit apoptosis. C) Both Bax and Bcl-2 stimulate apoptosis. D) Bax inhibits apoptosis while Bcl-2 stimulates apoptosis. E) Bax and Bcl-2 neither stimulate nor prevent apoptosis.
Bax stimulates apoptosis while Bcl-2 inhibits apoptosis
Which of the following proteins connects the extrinsic and intrinsic pathways? A) Puma. B) Bid C) Bad D) Bim E) Bik
Bid
The mechanism of DNA replication gives rise to the "end-replication problem" for linear chromosomes. Over time, this problem leads to loss of DNA from the ends of chromosomes. Loss of nucleotides during replication is balanced by addition of nucleotides by telomerase. In humans, however, telomerase is turned off in most somatic cells early in development, so that chromosomes become shorter with increasing rounds of replication. Consider one round of replication in a human somatic cell. Which one of the following statements correctly describes the status of the two daughter chromosomes relative to the parent chromosome? a) One daughter chromosome will be shorter at both ends; the other daughter chromosome will be normal at both ends. b) One daughter chromosome will be shorter at one end; the other daughter chromosome will be normal at both ends. c) One daughter chromosome will be shorter at both ends; the other daughter chromosome will be will be shorter at only one end. d) Both daughter chromosomes will be shorter at one end, which is the opposite end in the two chromosomes. e) Both daughter chromosomes will be shorter at one end, which is the same end in the two chromosomes. f) Both daughter chromosomes will be shorter at both ends.
Both daughter chromosomes will be shorter at one end, which is the opposite end in the two chromosomes
The difference in free energy between reactants and products is >0 for an important chemical reaction that occurs in the body, meaning that the reaction cannot occur spontaneously. Explain in 1-2 sentences how a cell gets this reaction to occur anyway.
By coupling the reaction with an energetically favorable reaction, to increase delta s and increase delta g
Which of the following correctly describes phosphorylation of a protein?A. It always increases the protein's activity. B. It always decreases the protein's activity. C. It can increase or decrease the protein's activity. D. It is catalyzed by a protein phosphatase. E. It is catalyzed by a protein kinase. F. It is an irreversible protein modification. G. It is a reversible protein modification.
C. It can increase or decrease the protein's activity E. It is catalyzed by a protein kinase G. It is a reversible protein modification
Which of the following proteins below is a kinase that places the activating phosphorylation on M-Cdk? A) Cdc25 B) CAK C) Wee1 D) p27 E) p21
CAK
What keeps cadherins from becoming "floppy"? A) syndecan binding. B) vinculin binding. C) G-protein coupled receptor activation. D) Ca2+ binding E) All of the above.
Ca2+ binding
What are the three phases of the Calvin Cycle? a) Carbon Release, Reduction, Regeneration of RuBP b) ATP generation, NADPH generation, Regeneration of RuBP c) Water splitting, Reduction, Carbon Fixation d) Carbon Fixation, Oxidation, Regeneration of RuBP e) Carbon Fixation, Reduction, Regeneration of RuBP
Carbon Fixation, Reduction, Regeneration of RuBP
What is the general term for biological pathways where larger molecules are broken down into smaller molecules?
Catabolic pathways
Which of the following molecules potentiates the progress of the cell cycle? A) Damaged DNA B) p27 CKI C) Cdc25 D) Wee-1 kinase E) p21 CKI
Cdc25
Which of the following proteins below is a phosphatase that removes the brake phosphorylation on M-Cdk? A) Cdc25 B) p21 C) Wee1 D) p27 E) CAK
Cdc25
Which is the enzyme that makes a single stand cut of the phosphodiester bonds in DNA: A. DNA gyrase B. DNA primase C. DNA helicase D. DNA topoisomerase I E. DNA topoisomerase II
DNA topoisomerase I
In the following schematic drawing, two DNA molecules are shown before and after the action of a protein that is also involved in the process of DNA replication in eukaryotes. What is this protein called? A. DNA ligase B. DNA gyrase C. DNA polymerase I D. DNA topoisomerase I E. DNA topoisomerase II
DNA topoisomerase II
Which of the following is the most difficult to accomplish by DNA-binding proteins: a) Distinguishing between C-G and G-C in the major groove b) Distinguishing between A-T and C-G in the major groove c) Distinguishing between A-T and T-A in the minor groove d) Distinguishing between C-G and T-A in the minor groove
Distinguishing between A-T and T-A in the minor groove
Your company has developed an organic molecule with commercial potential and you know how to produce it in the lab. You want to increase production and make as much of the molecule as possible, but the reaction has a positive ΔG°. What can you do that will help the reaction move toward your desired product? A. add an enzyme that does not couple to another reaction B. add some products initially to get the reaction primed C. decrease the concentration of the reactants. E. increase the concentration of reactants F. continually remove products G. the reaction can never occur spontaneously, so there is nothing you can do.
E. increase the concentration of reactants F. continually remove products
Which protein(s) is not involved in the generation and recognition of the mRNA 3' poly A tail? A. RNA polymerase II. B. CstF. C. Poly A polymerase. D. EJC proteins. E. CPSF.
EJC proteins
17) Imagine a protein that has been engineered to contain a nuclear localization signal, a nuclear export signal, a C-terminal peroxisomal targeting sequence, and a canonical endoplasmic reticulum (ER) signal sequence. With all of these signals, where would you expect to find the protein after its synthesis? A. Cytosol B. Nucleus C. ER D. Peroxisomes E. Shuttling between the cytosol and the nucleus
ER
1) Which of the following choices reflects the most appropriate order of locations through which a protein destined for the plasma membrane travels? a) ER-endosome-plasma membrane b) ER-lysosome-plasma membrane c) Golgi-lysosome-plasma membrane d) ER-Golgi-plasma membrane e) Golgi-ER-plasma membrane
ER-Golgi-plasma membrane
Explain how increases in the CstF protein in activated B cells lead to secretion of antibodies rather than their expression as membrane bound proteins.
Elevated levels of CstF activate the weak Cstf binding sites leading to shorter proteins leading to activated B cells secreting antibodies, whereas low CstF levels only bind to the strong polyadenylation sites
Which of the following is a major consequence of activation of phospholipase C-β (PLCβ) by the Gq trimeric GTPase? a) Elevation of intracellular cAMP levels, leading to the activation of protein kinase A b) Elevation of PIP3 levels in the plasma membrane, leading to the activation of protein kinase B c) Elevation of DAG and intracellular Ca2+ levels, leading to the activation of protein kinase C d) Elevation of DAG and IP3 in the plasma membrane, leading to the activation of protein kinase D e) Elevation of intracellular cGMP levels, leading to the activation of protein kinase G
Elevation of DAG and intracellular Ca2+ levels, leading to the activation of protein kinase C
The term for heat content in chemical bonds is: A) Thermodynamics B) Activation Energy C) Free Energy D) Entropy E) Enthalpy
Enthalpy
Reading frames and splicing. You have discovered a gene (below) that is alternatively spliced to produce several forms of mRNA in various cell types, three of which are shown in the figure below. The lines connecting the exons that are included in the mRNA indicate the splicing. From your experiments, you know that protein translation begins for all variants in exon 1. For all forms of the mRNA, the encoded protein sequence is the same in the regions of the mRNA that correspond to exons 1,4,5,6, 9, and 10 (indicated by arrows). Exons 2 and 3 are alternative exons used in different mRNA, as are exons 7 and 8. Which of the following statements about exons 2 and 3 must be true? (a) Exons 2 and 3 must have the same number of nucleotides. (b) Exons 2 and 3 must have different numbers of nucleotides. (c) Exons 2 and 3 must have the same numbers of nucleotides as 7 and 8 (d) Exons 2 and 3 must contain an integral number of codons (that is, the number of nucleotides divided by 3 must be an integer). (e) Exons 2 and 3 must contain a number of nucleotides that when divided by 3, leaves the same remainder (that is, 0, 1, or 2).
Exons 2 and 3 must contain a number of nucleotides that when divided by 3, leaves the same remainder (that is, 0, 1, or 2)
Which of the following is required for caspase-8 activation by death receptors: A) Bid. B) caspase-9 C) caspase-3 D) FADD E) cFLIP
FADD
) Interphase is made up of what stages of the cell cycle? A) G1 + G2 + S B) S + cytokinesis C) prophase + metaphase + anaphase + telophase D) cytokinesis + mitosis E) G0 + G1 + G2
G1 + G2 + S
What is the sequence of events in a typical eukaryotic cell cycle? A) G1 to G2 to S to mitosis to cytokinesis B) G1 to S to G2 to cytokinesis to mitosis C) G1 to S to G2 to mitosis to cytokinesis D) G1 to G2 to mitosis to S to cytokinesis E) S to G1 to G2 to mitosis to cytokinesis
G1 to S to G2 to mitosis to cytokinesis
Which of the following nucleotides is hydrolyzed in both transcription and in translation elongation? A. GTP B. TTP C. UTP D. CTP E. dATP
GTP
Which of the following pairs of codons might you expect to be read by the same tRNA as a result of wobble? a) CUU and UUU b) GAU and GAA c) AAU and AGU d) GUU and GUC e) GAU and CAU
GUU and GUC
) Which components of the extracellular matrix are mostly responsible for its ability to resist compressive and tensile forces, respectively? A) Collagens and glycoproteins B) Glycoproteins and collagens C) Glycosaminoglycans and glycoproteins D) Glycosaminoglycans and collagens E) Collagens and glycosaminoglycans
Glycosaminoglycans and collagens
8) The transmembrane protein bacteriorhodopsin uses sunlight as the source of energy to pump ______ out of the cell. a) Mg2+ b) Na+ c) K+ d) H+ e) Ca 2+
H+
Which of the following chaperone in the cytoplasm is the first to bind unfolded polypeptides coming of the ribosome? A. HSP40.B. HSP90.C. HSP70.D. HSP60.E. HSP27.
HSP40
Which of the following chaperone acts as an isolation chamber for protein folding? A. HSP40. B. HSP90. C. HSP70. D. HSP60. E. HSP27.
HSP60
The type of protein that DNA is wrapped around is called? a) Centrosomes b) Kinetochores c) Keytones d) Protophones e) Histones
Histones
Which statement best explains why humans can digest starch, but not cellulose: A. Starch and Cellulose are made up of different sugars. B. Cellulose is highly branched, Starch is not. C. Starch is highly branched, Cellulose is not. D. In cellulose and starch, the sugars are connected by different kinds of linkages. E. Cellulose is intertwined with itself.
In cellulose and starch, the sugars are connected by different kinds of linkages
Which of the following acronyms refers to a special way that allows a eukaryotic mRNA to be translated bi-cistronically? A) APROS. B) ERUS. C) CAP. D) IRES. E) ORES.
IRES
Which of the following is not true about import in mitochondria: A) Imported proteins often are crossing both membranes at the same time. B) Imported precursor proteins have N-terminal signal sequences that are usually removed after use. C) Transport through the double membrane is driven in part by an H+ gradient across its second (inner) membrane. D) Hsp70 family chaperones inside the organelle assist in protein translocation during import. E) Import utilizes both GTP and ATP.
Import utilizes both GTP and ATP
How does an allosteric inhibitor work? A. It binds to a site other than the active site, causing a conformational change in the enzyme that makes the active site less accommodating to the substrate. B. It binds to a site other than the active site, causing a conformational change in the enzyme that forces the product to leave the active site. C. It interacts covalently with the substrate, preventing it from fitting into the enzyme's active site. D. It outcompetes the substrate molecule and binds to the active site, preventing substrate molecules from binding there.
It binds to a site other than the active site, causing a conformational change in the enzyme that makes the active site less accommodating to the substrate.
ATP is the main energy currency in cells, and it can especially be used to drive condensation reactions that produce macromolecular polymers. How does ATP typically catalyze a condensation reaction, which by itself is energetically unfavorable? A. It transfers its terminal phosphate to an enzyme and is released as ADP. B. It transfers its two terminal phosphates to an enzyme, and is released as AMP. C. It covalently attaches to both of the substrates. D. It transfers its terminal phosphate to one of the substrates and is released as ADP. E. It covalently attaches to the enzyme, forming an enzyme-AMP adduct.
It transfers its terminal phosphate to one of the substrates and is released as ADP
Which one of the following statements about the newly synthesized strand of a human chromosome is correct? a) It was synthesized from a single origin solely by continuous DNA synthesis. b) It was synthesized from a single origin solely by discontinuous DNA synthesis. c) It was synthesized from a single origin by a mixture of continuous and discontinuous DNA synthesis. d) It was synthesized from multiple origins solely by continuous DNA synthesis. e) It was synthesized from multiple origins solely by discontinuous DNA synthesis. f) It was synthesized from multiple origins by a mixture of continuous and discontinuous DNA synthesis.
It was synthesized from multiple origins by a mixture of continuous and discontinuous DNA synthesis
Cells use membranes to help maintain set ranges of ion concentrations inside and outside the cell. Which of the following ions is the most abundant inside a typical mammalian cell? a) Cl- b) K+ c) Ca2+ d) Na+ e) PO43-
K+
A resident ER protein has got accidentally taken up in a vesicle and made its way to the golgi. How does it get back to the ER: a) CCV vesicle b) Mannose 6 phosphate c) KVRE retrieval pathway d) COPII coated vesicle e) KDEL mediated return
KDEL mediated return
Which of the following motor proteins are more directly involved in anaphase B? A. Kinesin-5 on interpolar microtubules and dynein on kinetochore microtubules B. Kinesin-13 on kinetochore microtubules and dynein on astral microtubules C. Kinesins 4 and 10 on interpolar and astral microtubules and dynein on kinetochore microtubules D. Kinesin-5 on interpolar microtubules and kinesins 4 and 10 on interpolar and astral microtubules E. Kinesin-5 on interpolar microtubules and dynein on astral microtubules
Kinesin-5 on interpolar microtubules and dynein on astral microtubules
Which amino acid pairs are more likely to be located within the interior (middle) of biological membranes? a) Threonine and Histidine b) Glutamate and Glutamine c) Leucine and Tryptophan d) Arginine and Lysine e) Serine and Alanine
Leucine and Tryptophan
In G2, there are typically high levels of the cyclin-M. Why is M-Cdk not active during G2 if the mitotic cyclin is present? A) M-Cdk requires ubiquitination to be activated B) M-Cdk does not bind to the mitotic M-cyclin. C) M-Cdk is bound by CKIs D) M-Cdk is also negatively regulated by phosphorylation. E) Cyclin M is protected from binding to Cdk1 by inhibitory proteins.
M-Cdk is also negatively regulated by phosphorylation
Which of the following proteins is required for necroptosis? A) PARP B) caspase-9 C) Apaf-1 D) MLKL E) Bax
MLKL
The transplant drug cyclosporin A prevents what kind of cell death? A) parthanatos B) necroptosis C) apoptosis D) MPT-driven necrosis E) autophagic type II death
MPT-driven necrosis
Complex II is able to steal electrons from water using which metal atoms? a) Magnesium b) Iron c) Molybdenum d) Manganese e) Mendelevium
Manganese
Which of the following pathways targets hydrolases for the lysosome: a) Endocytosis b) Macropinocytosis pathway c) Phagocytosis d) Autophagy e) Mannose 6 phosphate receptor pathway
Mannose 6 phosphate receptor pathway
69) What channels protect bacterial cells against extreme osmotic pressures? a) classical aquaporins b) Mechanosensitive channels c) voltage gated Ca2+ channels d) voltage gated H2O channels e) voltage gated Na+ channels
Mechanosensitive channels
Which of the following protein complexes pumps the most protons across the membrane during a single electron transport event? a) photosystem I b) succinate dehydrogenase (complex II) c) NADH dehydrogenase (complex I) d) cytochrome c oxidase (complex IV) e) ATP synthase
NADH dehydrogenase (complex I)
Active transport requires the input of energy into a system so as to move solutes against their electrochemical and concentration gradients. Which of the following is not one of the common ways to perform active transport? a) Na+-coupled b) Mg+ -coupled c) ATP-driven d) light-driven e) all of the above are common ways of active transport.
Mg+ -coupled
24) Which of the following the molecules from the list below would be the least permeable in a lipid bilayer without proteins. a. Mg2+ b. O2 c. CO2 d. H2O e. Ethanol
Mg2+
The myoglobin protein does not have a quanternary structure. What can you infer about myoglobin? a) Myoglobin does not have alpha-helical or beta-pleated structures. b) Myoglobin is made of only one polypeptide chain. c) Myoglobin made of several polypeptide chains. d) Myoglobin lacks hydrogen bonds e) Myoglobin does not have normal amino acids.
Myoglobin is made of only one polypeptide chain
51) ER glycosylation is different from glycosylation in the Golgi in that ER glycosylation is: a) added at N-terminal residues b) N -linked c) O-linked d) Lysine linked e) Arginine linked
N -linked
Proteins are synthesized from: a) 5' to 3' b) 3' to 5' c) N-terminal to C-terminal d) C-terminal to N-terminal e) nucleotides
N-terminal to C-terminal
NADH and NADPH are similar, but the difference between NADH and NADPH is that: a) NADH is used as an active carrier molecule, NADPH does not carry energy. b) NADPH is used as an active carrier molecule, NADH does not carry energy. c) NADH is used in catabolic pathways, NADPH is used in anabolic pathways. d) NADPH is used in catabolic pathways, NADH is used in anabolic pathways. e) one carries electrons and protons, the other does not.
NADH is used in catabolic pathways, NADPH is used in anabolic pathways
Which of the following would NOT be expected to activate the Unfolded Protein Response in the ER when large amounts of unfolded proteins accumulate: a) IRE1 b) PERK c) ATF6 d) NF-Kappa B e) all of these mediate the Unfolded Protein Response
NF-Kappa B
40) T-snares are intertwined and stuck together with a V-snare. Which molecule has the function of getting them apart: a) NSF b) NRA c) Snarin d) Rab e) GTP-dependent Snare thingy enzyme
NSF
55) Which of the following ions is the most abundant outside a typical mammalian cell? a) K+ b) Na+ c) Ca2+ d) Mg2+ e) PO43-
Na+
22) A typical cells spends almost 1/3 of its total energy on powering this transporter: a) Na+-glucose symporter b) Ca2+-pump c) Na+-Mg+ pump d) Na+-independent Cl--HCO3- exchanger e) Na+-K+ pump
Na+-K+ pump
Which of the following statements accurately compares apoptosis with necrosis? A) Apoptosis results in cell rupture, which releases intracellular contents, while necrosis does not. B) Necrosis causes an inflammatory response, but apoptosis does not. C) Both apoptosis and necrosis are triggered quickly as the result of physical cell injury. D) Both apoptosis and necrosis are largely important as tools in embryological development. E) Neither apoptosis nor necrosis require energy from ATP.
Necrosis causes an inflammatory response, but apoptosis does not
What is the major microtubule-organizing center in plant cells? A. The centrosome B. The cell cortex C. The golgi apparatus D. The spindle pole body E. None of the above
None of the above
What is the rate-limiting step in the growth of actin filaments and microtubules? A) ATP or GTP hydrolysis B. Reaching steady state C. Instability on the plus end D. Nucleation E. Growth at the plus end.
Nucleation
28) Which of the following the molecules from the list below would be the most permeable in a lipid bilayer without proteins. a. Mg2+ b. Glucose c. Ethanol d. O2 e. RNA
O2
What is the final electron acceptor in aerobic respiration? a) CO2 b) O2 c) ATP d) NADPH e) Glucose
O2
73) Neuromuscular transmission involves the sequential activation of several ion channels. Which one of these events occurs last? A. Opening of voltage-gated Na+ channels in the muscle cell plasma membrane. B. Opening of Ca2+ release channels in the sarcoplasmic reticulum membrane. C. Opening of ionotropic acetylcholine receptors. D. Opening of voltage-gated Ca2+ channels in the T tubule. E. Opening of voltage-gated Ca2+ channels in the end of the neuron in response to a depolarization event.
Opening of Ca2+ release channels in the sarcoplasmic reticulum membrane
74) Neuromuscular transmission involves the sequential activation of several ion channels. Which one of these events occurs as the initial event on the muscle cell? A. Opening of voltage-gated Na+ channels in the muscle cell plasma membrane. B. Opening of Ca2+ release channels in the sarcoplasmic reticulum membrane. C. Opening of ionotropic acetylcholine receptors. D. Opening of voltage-gated Ca2+ channels in the T tubule. E. Opening of voltage-gated Ca2+ channels in the end of the neuron in response to a depolarization event.
Opening of ionotropic acetylcholine receptors.
72) Neuromuscular transmission involves the sequential activation of several ion channels. Which one of these events occurs first? A. Opening of voltage-gated Na+ channels in the muscle cell plasma membrane. B. Opening of Ca2+ release channels in the sarcoplasmic reticulum membrane. C. Opening of ionotropic acetylcholine receptors. D. Opening of voltage-gated Ca2+ channels in the T tubule. E. Opening of voltage-gated Ca2+ channels in the end of the neuron in response to a depolarization event.
Opening of voltage-gated Ca2+ channels in the end of the neuron in response to a depolarization event
Rolling of a macrophage inside of a blood vessel is most linked to what molecule? A) cadherin. B) elastin. C) P-selectin. D) vinculin. E) claudin.
P-selectin
The Sarcoplasmic Reticulum Ca2+/proton exchange pump is this kind of pump ABC transporter (A), P-type pump (B), or a V-type pump (C).
P-type pump
The pumps in this family are phosphorylated at a key Asp residue in each transport cycle ABC transporter (A), P-type pump (B), or a V-type pump (C).
P-type pump
Which of the following molecules is NOT responsible for direct/indirect activation of caspase-9: A) ATP B) APAF-1 C) cytochrome C D) PARP E) BAX
PARP
Which of the following proteins is required for parthanatos? A) PARP B) caspase-9 C) Apaf-1 D) MLKL E) Bax
PARP
Which of the following helps maintain the contact between the polymerase and DNA during RNA synthesis: a) clamp loader protein b) DNA primase c) single strand DNA binding protein d) PCNA e) none of the above
PCNA
Which signaling is where a signaling molecule is released from one cell and binds a receptor on a nearby cell? a) Juxtacrine Signaling b) Paracrine Signaling c) Autocrine Signaling d) Synaptic Signaling e) Endocrine Signaling
Paracrine Signaling
Peroxisome proteins are recruited into the peroxisome from the ER by means of: a) sec61 b) the Get complex c) Pex 19 d) calnexin e) glucosyl tranferase
Pex 19
What change in a cell characteristic is a signal (eat me!) to surrounding cells that a cell is going through apoptosis? A) membrane permeabilization B) cadherin exposure on the plasma membrane C) Cell swelling D) Phosphatidylserine is flipped from the cytoplasmic side of the plasma membrane to the outer side of the membrane. E) Phosphatidylserine is flipped from the extracellular side of the plasma membrane to the inner side of the membrane.
Phosphatidylserine is flipped from the extracellular side of the plasma membrane to the inner side of the membrane
In plant photosynthesis, which component generates the energy to produce NADPH? A) Photosystem II B) the b6-f complex C) Photosystem I D) Rubisco E) plastocyannin
Photosystem I
) Which of the following polymerases does not require a template: a) RNA polymerase I b) Telomerase c) DNA primase d) Poly A polymerase e) DNA polymerase III
Poly A polymerase
Explain in 1-2 sentences why the interaction of the mRNA cap binding proteins and the poly A binding proteins leads to greater efficiency in the process of eukaryotic translation.
Poly A tail signals the process, capping stabilizes, ribosome is able to hop back on and restart translation
Virtually all peptide bonds in proteins occur in the trans configuration. The exception to this rule is one particular amino acid, in which 10% is found in the cis configuration. This particular amino acid is: a) Trypophan b) Phenylalanine c) Alanine d) Proline e) Histidine
Proline
70) What would happen if you artificially limited all Ran-GAP activity to the nucleus and all Ran-GEF activity to the cytosol? a) Protein import into the nucleus would be reversed, but export would be unaffected. b) Protein import into the nucleus would be stalled, but export would be unaffected. c) Both import and export of nuclear proteins would be stalled, as they lose their directionality. d) Proteins containing an NLS would be actively exported from the nucleus and NES-containing proteins would be actively imported. e) Nothing would change; this is the normal Ran-GAP and Ran-GEF distribution.
Proteins containing an NLS would be actively exported from the nucleus and NES-containing proteins would be actively imported.
Name the 4 major naturally occurring classes of macromolecules (biopolymers) in a human body. In the space next to each answer, name the kind of monomer that the indicated macromolecule is made of. 48 ________________ _________________ 49 ________________ _________________ 50 ________________ _________________ 51 ________________ _________________
Proteins-amino acids Carbohydrates-sugar Lipids-fatty acids nucleic acids-nucleotides
Which of the following proteins is activated by p53 in response to DNA damage? A) Bik B) Bim C) Puma D) Bad E) Bid
Puma
Ubiquinone/Ubiquinol in mitochondria and plastoquinone/plastoquinol participate in multiple transfers of electrons, as well as a recycling mechanisms that pump protons. These cycles are referred to as the _______ cycles. a) P b) Z c) Q d) R e) D
Q
Which of the following is a kinase required for necroptosis? A) PARP B) RIPK3 (RIP3) C) Apaf-1 D) MPK E) ERK
RIPK3 (RIP3)
Which of the following polymerases is primarily responsible for producing mRNAs in eukarotes: a) RNA polymerase I b) RNA polymerase II c) RNA polymerase III d) Poly A polymerase e) DNA polymerase I
RNA polymerase II
7) What is the main way in which a vesicle or small organelle changes its identity to become a different compartment? a) change of t-Snares b) platoquinone-mediated maturation c) Rab cascades d) change of v-Snares proteins e) macropinocytosis
Rab cascades
Which of the following sequences are responsible for binding to the general transcription factor that positions the RNA polymerase at the proper start site for transcription to begin a) The Kozak's consensus sequence b) The Shine-Dalgarno sequence c) The BRE d) The TATA Box e) The MTE f) The DPE g) The INR h) all of the above
The BRE
What is true about the G proteins bound to G protein-coupled receptors (GPCRs) with relationship to Ras? a) Ras is an enzyme, and the G proteins bound to GPCRs are not enzymes. b) They both are active when GDP is bound. c) They both have three separate subunits. d) Ras is a small single subunit protein, while the GPCR proteins are heterotrimeric. e) They both are inactive when GTP is bound.
Ras is a small single subunit protein, while the GPCR proteins are heterotrimeric
In the Calvin Cycle, the five carbon sugar called _______? a) ribose b) G3P c) NADPH d) RuBP e ) PGA
RuBP
The world's most plentiful enzyme by bulk amount is : a) succinate dehydrogenase (complex II) b) Cytochrome c c) Rubisco d) The large subunit of NADH oxidase (from Complex I) e) Cytochrome C oxidase (from Complex IV)
Rubisco
DNA replication takes place in which phase of the cell cycle: a) G1 b) G2 c) M d) S e) G0
S
During what stages of the cell cycle are sister chromatids bound together by cohesin? A) G1, S, G2 B) S, G2 C) G1, S D) S, G2, prophase, metaphase E) S, G2, prophase, metaphase, anaphase, telophase
S, G2, prophase, metaphase
Which protein binds to regions within the whole exon and defines them for the splicing machinery? A. snRNPs. B. hnRNPs. C. SR proteins. D. EJC proteins. E. CBCs.
SR proteins
Which of the following RNA(s) functions in the recognition of nucleotides that need to be modified in ribosomal RNAs (rRNAs)? a. Transfer RNAs (tRNAs) b. Small hairpin RNAs (shRNAs) c. Small nucleolar RNAs (snoRNAs) d. Small nuclear RNAs (snRNAs) e. Small interfering RNAs (siRNAs) f. MicroRNAs (miRNAs)
Small nucleolar RNAs (snoRNAs)
Which of the following general transcription factors unwinds DNA at the transcription start point: a) DNA helicase b) TFIIB c) TFIID d) TFIIH e) TFIIE f) TFIIF
TFIIF
Which of the following general transcription factors phosphorylates the polymerase to release it from the other general transcription factors and begin transcription: a) TFIIB b) TFIID c) TFIIE d) TFIIF e) TFIIH
TFIIH
As the Entropy (DS) increases which of the following is likely to be true: A. The reaction will be less likely to be spontaneous. B. The reaction will be more likely to be endergonic. C. The Free Energy (DG) is more likely to be negative. D. The free Energy (DG) is less likely to be negative. E. Less energy will be available to do work.
The Free Energy (DG) is more likely to be negative
Which statement is true of the differences between kinesin and myosin in terms of movement? A) Kinesins move to the plus end of microtubules, Myosins move to the minus end of actin filaments. B) Myosins move to the plus end of microtubules, Kinesins move to the minus end of actin filaments. C) The Kinesin power stroke (neck linker "unzipping") is activated by ATP hydrolysis, the power stroke of myosin is due to ejection of inorganic phosphate. D) The power stroke of myosin results from ATP hydrolysis, The Kinesin power stroke (neck linker "unzipping") is activated by ejection of inorganic phosphate. E) Both the Kinesin power stroke (neck linker "unzipping") and the power stroke of myosin is activated by ATP hydrolysis.
The Kinesin power stroke (neck linker "unzipping") is activated by ATP hydrolysis, the power stroke of myosin is due to ejection of inorganic phosphate
) The sequence in eukaryotes that is recognized that defines where the ribosomes start translation is: a) The BRE b) The TATA Box c) The MTE d) The DPE e) The INR f) The Kozak's consensus sequence g) The Shine-Dalgarno sequence h) all of the above
The Kozak's consensus sequence
The sequence in prokaryotes that is recognized that defines where the ribosomes start translation is: a) The Kozak's consensus sequence b) The Shine-Dalgarno sequence c) The BRE d) The TATA Box e) The MTE f) The DPE g) The INR h) all of the above
The Shine-Dalgarno sequence
The ribosome is important for catalyzing the formation of peptide bonds. Which of the following statements is true? (a) The number of rRNA molecules that make up a ribosome greatly exceeds the number of protein molecules found in the ribosome. (b) The large subunit of the ribosome is important for binding to the mRNA. (c) Once the large and small subunits of the ribosome assemble, they will not separate from each other until degraded by the proteasome. (d) The catalytic site for peptide bond formation is formed primarily from an rRNA. (e) The tRNA molecule does not play any role in the active site- it only brings an amino acid to the ribosome.
The catalytic site for peptide bond formation is formed primarily from an rRNA.
What would happen if the anaphase-promoting complex/cyclosome (APC/C) failed to ubiquitinate securin? A) The cohesin complex will be destroyed, and the cell will remain in metaphase. B) Securin will remain intact and therefore will degrade cohesin, allowing the cell to enter anaphase. C) Separase will be marked for degradation by securin, preventing the cell from entering anaphase. D) The cohesin complex will persist, preventing the cell from entering anaphase. E) Cohesins will break allowing the chromosomes to separate.
The cohesin complex will persist, preventing the cell from entering anaphase
) Which of the following is the most accurate description of differences between the extrinsic and intrinsic apoptotic pathways: A) The intrinsic pathway results in the activation of caspases, the extrinsic pathway does not. B) The extrinsic pathway results in the activation of caspases, the intrinsic pathway does not. C) The intrinsic pathway is triggered by transmembrane receptors carrying death domains; the extrinsic pathway is triggered by mitochondrial permeabilization. D) The extrinsic pathway is triggered by transmembrane receptors carrying death domains; the intrinsic pathway is triggered by mitochondrial permeabilization. E) The extrinsic pathway involves caspases with large prodomains, but the intrinsic pathway does not involve any caspases with long prodomains.
The extrinsic pathway is triggered by transmembrane receptors carrying death domains; the intrinsic pathway is triggered by mitochondrial permeabilization
30) Which of the following is an ABC pump that hydrolyzes two ATP molecules per transport cycle? a) The cystic fibrosis transmembrane conductance regulator protein b) The Ca2+-pump c) The Na+-K+ pump d) The multidrug resistance protein e) The V-type ATPase
The multidrug resistance protein
How does phosphorylation most commonly control protein activity?A. The phosphate group alters the primary structure of the protein B. The phosphate group serves as an added source of energy for a protein. C. The phosphate group, with its positive charges, temporarily relieves feedback inhibition. D. The phosphate group, with its negative charges, prevents other negatively charged molecules from interacting with the protein. E. The phosphate group induces a change in the protein's conformation.
The phosphate group induces a change in the protein's conformation
What happens during Anaphase B? A) Kinetochores are pulled toward the poles. B) The spindle poles move apart. C) The spindle apparatus disassembles. D) The nuclear envelope reforms. E) The APC/C gets activated for the first time.
The spindle poles move apart
Which one of the following is the main reason that a typical eukaryotic gene is able to respond to a far greater variety of regulatory signals than a typical prokaryotic gene or operon? a) Eukaryotes have three types of RNA polymerase. b) Eukaryotic RNA polymerases require general transcription factors. c) The transcription of a eukaryotic gene can be influenced by proteins that bind far from the promoter. d) Prokaryotic genes are packaged into nucleosomes. e) Potential prokaryotic signals sequences are removed by the spliceosome during RNA splicing.
The transcription of a eukaryotic gene can be influenced by proteins that bind far from the promoter
Which of following is NOT true of intermediate filaments: a) They have the smallest persistence length of cellular filaments. b) Their subunits bind ATP and hydrolyze it. c) They lack polarity. d) They have the highest tensile strength of cellular filaments. e) They form coiled-coil interactions between the subunits.
Their subunits bind ATP and hydrolyze it
ADP-ribosylation is the addition of one or more ADP-ribose modifications to a protein. Cholera toxin ADP-ribosylates the α subunit of stimulatory G protein (Gs), thereby blocking GTP hydrolysis, while pertussis toxin ADP-ribosylates the α subunit of an inhibitory G protein (Gi) and prevents interaction with the receptor. What is the effect of these toxins on the concentration of intracellular cAMP? a) They both tend to decrease cAMP concentration. b) They both tend to increase cAMP concentration. c) Cholera toxin tends to decrease cAMP concentration, whereas pertussis toxin tends to increase cAMP concentration. d) Cholera toxin tends to increase cAMP concentration, whereas pertussis toxin tends to decrease cAMP concentration. e) none of the above.
They both tend to increase cAMP concentration
Why are glycoaminoglycans usually stiff and extended in nature, rather than being globular? A) They are not large enough to fold back on each other. B) Their backbone cannot rotate. C) They have a high density of positive charges. D) They have a high density of negative charges. E) Subunits are always held together by covalent interactions.
They have a high density of negative charges
Which of the following is NOT an anchoring junction? A) Adherens junction B) Desmosome C) Tight junction D) Hemidesmosome E) Actin-linked cell-matrix junction
Tight junction
Which of the following is the largest known protein: A) Nebulin B) Troponin C) Myosin II D) calmodulin E) Titin
Titin
What is the primary function of a protein kinase? a) To remove phosphate groups from proteins b) To add phosphate groups onto proteins c) To phosphorylate GDP to generate GTP d) To cleave membrane phospholipids e) act as an adaptor protein
To add phosphate groups onto proteins
68) Which of the following is not true about import in chloroplasts: A) Imported proteins often are crossing both inner and outer membranes at the same time. B) Imported precursor proteins have N-terminal signal sequences that are usually removed after use. C) Transport through the double membrane is driven in part by an H+ gradient across its second (inner) membrane. D) Transport through the thylakoid membrane is driven in part by an H+ gradient across the thylakoid membrane. E) Import utilizes both GTP and ATP.
Transport through the double membrane is driven in part by an H+ gradient across its second (inner) membrane
Which of the following is NOT required for Smooth muscle contraction: A) Ca2+ release from the sarcoplasmic reticulum B) Troponin C) Myosin II D) calmodulin E) Myosin Light Chain Kinase
Troponin
Which of the following is important for sensing calcium during skeletal muscle contraction: A) Nebulin B) Troponin C) Myosin II D) calmodulin E) Titin
Troponin
Which proteins are involved in nonsense-mediated degradation? A. U2 auxillary factor2.B. branch point binding protein.C. Poly A binding proteinsD. snoRNPs.E. Upf proteins
Upf proteins
The pumps in this family are responsible for the acidification of lysosomes ABC transporter (A), P-type pump (B), or a V-type pump (C).
V-type pump
21) This family of ATPases acidify lysosomes. a) P-type pumps b) ABC transporters c) V-type pumps d) F-type pumps e) Permeases
V-type pumps
In a triglyceride, what type of interaction is likely to be occurring between hydrogen atoms bound to carbon in different fatty acid chains? a) ionic bonds b) electrostatic interactions c) covalent bonds d) hydrogen bonds e) Van der Waals interactions
Van der Waals interactions
Chlorophylls absorb which colors (wavelengths) of light? A) Blue and Green B) Green and Yellow C) All visible wavelengths D) Green, Yellow, and Orange E) Violet, Blue, and Red
Violet, Blue, and Red
Which of the following are the cells most killed by the extrinsic apoptosis pathway? A) Cells with damaged DNA. B) Cells in which Calcium is released in large quantities. C) Virus infected cells. D) Irradiated cells. E) Developing nerve cells that fail to make profitable connections.
Virus infected cells
19) What is the correct and/or best explanation as to why there is a higher entropy (disorder) for the cellular system in lipid bilayers, thus meaning that bilayer formation is energetically favorable? a) Fatty acid tails are locked into position and cannot rotate. b) Water molecules would more organized around hydrophobic molecules than they would in normal fluids. c) Hydrogen bonds form between neighboring polar head groups in the bilayer. d) Water molecules would be less organized around hydrophobic molecules than they would in normal fluids. e) Fatty acid tails are hydrophilic.
Water molecules would more organized around hydrophobic molecules than they would in normal fluids
According to the 2nd law of thermodynamics, the entropy (disorder) of the universe is constantly increasing. Explain in 1-2 sentences why this does not prevent living systems being able to increase the order (decrease the entropy) in their cells.
When we decrease entropy in our cells, we also increase the entropy of the rest of the universe at the same time
Which of the following is a molecule stabilizes the plus ends of microtubules, and helps to accelerate their assembly? a) XMAP215 b) γ-Tubulin c) GTP D) kinesin-13 e) MAPs
XMAP215
27) Which of the following does not help to bend membranes: a) the coat proteins b) the cargo receptors. c) adapter molecules d) a BAR domain proteins. e) a dynamin oligomer.
a dynamin oligomer
Compared to the human genome, the genome of yeast typically has ... a) more repetitive DNA. b) longer genes. c) a higher fraction of coding DNA. d) longer chromosomes. e) more introns.
a higher fraction of coding DNA
What do eukaryotic cells have that prokaryotes lack?A) nucleic acids B) ribosomes C) a cell wall D) a means of using chemical energy E) a nucleus and membrane-bound organelles
a nucleus and membrane-bound organelles
What is separase? A) a protein that marks a protein called securin for destruction B) a protein that is part of the cohesin complex C) a protein that destroys cohesin through its protease activity D) a protein that targets the mitotic cyclin for degradation D) a protein that allows two halves of the cell to separate during cytokinesis
a protein that destroys cohesin through its protease activity
12) The KDEL sequence is: a) a sequence for the cytosolic import into the ER. b) the sequence that is important for import into peroxisomes. c) a signal that directs ER resident proteins to return to the ER through vesicles. d) the sequence that is important for import into mitochondria. e) a sequence important for exocytosis.
a signal that directs ER resident proteins to return to the ER through vesicles
If you were to replace the phosphate group of a phospholipid with a fatty acid chain, you would have: A. a glycerol B. a triglyceride. C. a cholesterol. D. a glycolipid. E. a sphingolipid.
a triglyceride
CpG methylation (5-methyl cytosine) would interfere with recognition in which groove interactions a) Distinguishing between C-G in the major groove b) Distinguishing between G-C in the major groove c) Distinguishing between C-G the minor groove d) Distinguishing between G-C in the minor groove e) all of the above
a) Distinguishing between C-G in the major groove b) Distinguishing between G-C in the major groove
92) Which of the following is involved in getting a ribosome translocated to the rough ER. a) an ER signal sequence b) The signal-recognition particle (SRP) c) A KDEL sequence d) SRP receptor e) the membrane potential of the ER f) all of these are involved
a) an ER signal sequence b) The signal-recognition particle (SRP) d) SRP receptor
Why do cells prefer multistep oxidation processes? a) direct oxidation leads to a loss of most energy in the form of heat. b) cells can store more energy by capturing a little at a time. c) the activation energies of a set of small steps can be more easily overcome by individual enzymes. d) storing energy from multiple steps in individual carrier molecules allows the cell to use energy a little at a time. e) all of the above are true
all of the above are true
The stage of mitosis characterized by the physical separation of sister chromatids is called A) metaphase. B) anaphase. C) prometaphase. D) telophase. E) prophase.
anaphase
This form of cell death is the most often cell death pathway activated by physiological stimuli? A) parthanatos B) necroptosis C) apoptosis D) MPT-driven necrosis E) autophagic type II death
apoptosis
60) Many cells store lipids in droplets of varying sizes. These droplets ... a) have mostly protein-free bilayer membranes. b) are composed primarily of charged amphiphilic lipids. c) are produced by and released from the Golgi apparatus. d) are enclosed by a phospholipid monolayer (instead of a bilayer). e) mostly store cholesterol and phospholipids.
are enclosed by a phospholipid monolayer (instead of a bilayer)
Where or when does RNA capping at the 5' end of the transcript take place?A) as an RNA is being transcribed B) after RNA splicing C) once an RNA is released by RNA polymerase D) within the nuclear pore complex E) when an RNA exits the nucleus
as an RNA is being transcribed
Which of the following accurately describes the difference(s) between NADH and NADPH: a) NADPH carries energy primarily in phosphate bonds, NADH carries electrons; b) NADPH is a phosphorylated version of NADH. c) one carries electrons and protons, the other does not. d) NADPH carries electrons; NADH carries energy in phosphate bonds. e) NADH is used in mitochondria, NADPH is used in chloroplasts. f) NADPH is used in mitochondria, NADH is used in chloroplasts.
b) NADPH is a phosphorylated version of NADH. e) NADH is used in mitochondria, NADPH is used in chloroplasts.
Which of the following RNAs are extensively posttransciptional modified (i.e. have chemically modified sugars and nitrogenous bases): a. messenger mRNA (mRNA) b. ribosomal RNAs (rRNAs) c. small interfering RNAs (siRNAs) d. short hairpin RNAs (shRNAs) e. transfer RNAs (tRNAs) f. microRNAs (miRNAs) g. snRNAs h. snoRNA
b. ribosomal RNAs (rRNAs) e. transfer RNAs (tRNAs)
Each aminoacyl-tRNA synthetase activates a certain amino acid by attaching it to its corresponding tRNA(s) through a high-energy linkage... a) between the amino group of the amino acid and the 3' hydroxyl group of the tRNA. b) between the amino group of the amino acid and the 5' hydroxyl group of the tRNA. c) between the amino group of the amino acid and the 3' or 2' hydroxyl group of the tRNA. d) between the carboxyl group of the amino acid and the 5' hydroxyl group of the tRNA. e) between the carboxyl group of the amino acid and the 3' or 2' hydroxyl group of the tRNA
between the carboxyl group of the amino acid and the 3' or 2' hydroxyl group of the tRNA
Which of the following inhibits caspase-8 activation by death receptors: A) Bid. B) caspase-9 C) caspase-3 D) FADD E) cFLIP
cFLIP
Expression of which of the following molecules is associated with separation of like expression cell types: A) cadherins. B) connexins. C) syndecan.s D) periecans. E) claudins.
cadherins
32) Channel proteins in cellular membranes ... a) form pores that are always open.. b) always require ATP. c) can only mediate passive transport. d) interact strongly with the solute(s) that they transport e) undergo a conformational change every time they transport a solute.
can only mediate passive transport
) The role of the antenna complex in a photosystem is to: A) transfer excited electrons to the primary electron acceptor. B) generate glucose. C) generate NADPH. D) capture photons from sunlight. D) fix carbon to RuBP
capture photons from sunlight
11) Molecules to be packaged into vesicles for transport are selected by ________. a) clathrin. b) cargo receptors c) dynamin. d) SNAREs. e) COPII.
cargo receptors
Which of the following is an executioner caspase: A) Caspase-8. B) caspase-9 C) caspase-7 D) caspase-10 E) caspase-2
caspase-7
Which caspase is likely to be found at the cell membrane when initially activated? A) caspase-3 B) caspase-6 C) caspase-7 D) caspase-8 E) caspase-9
caspase-8
Which initiator caspase is activated by mitochondrial permeabilization when initially activated? A) caspase-3 B) caspase-6 C) caspase-7 D) caspase-8 E) caspase-9
caspase-9
What is the major component of gap junctions? A) cadherin. B) claudin C) syndecan. D) periecan. E) connexin.
connexin
Golgi glycosylation of proteins is different from ER glycosylation in that Golgi glycosylation is: a) created by adding one sugar at a time b) added only to asparagine residues c) used to determine how long a protein has been in the Golgi d) transferred from Dolichol as a chain of sugars e) used to determine whether a protein has been folded in the Golgi
created by adding one sugar at a time
What factor from the electron transport chain is released from the mitochondria, ultimately resulting in caspase-9 activation. A) ubiquinone B) cytochrome c oxidase C) cytochrome c D) NADH dehydrogenase E) succinate dehydrogenase
cytochrome c
Which of the following is not a component of mammalian plasma membranes: a) phospholipid bilayer b) transmembrane proteins c) cytoplasmic glycoproteins d) interior protein network e) exterior glycoproteins and glycolipids
cytoplasmic glycoproteins
What is the trigger for anaphase to begin: (corrected) A) activation of S-Cdk by APC/C B) activation of M-Cdk by APC/C C) degradation of M-cyclin by APC/C D) activation of S-Cdk by securin E) activation of M-Cdk by securin
degradation of M-cyclin by APC/C
Macromolecules are polymers made by covalently linking monomers through what kind of reaction? A. isomerization reaction B. hydration reaction C. dehydration reaction D. hydrolysis reaction E. ionic reaction
dehydration reaction
One cell sends second messengers to another cell through gap junctions. What type of signaling would this be considered? a) direct contact b) paracrine c) endocrine d) synaptic e) autocrine
direct contact
Which of the following molecular motors are primarily used for moving transport vesicles toward the cell interior? A) kinesin-5 B) myosin II C) kinesin-1 D) myosin V E) dynein I
dynein I
Of the following, which is the best example of a single kind of ligand that activates very diverse responses in different cell types and in the same cells in distinct tissues? a) WNT b) EGF c) insulin d) epinephrine e) glucagon
epinephrine
Receptor Tyrosine Kinases vary most in their: a) mechanism of activation b) intracellular kinase domains c) extracellular ligand binding domains d) use of SH2 adaptor proteins e) heterodimerization
extracellular ligand binding domains
Tertiary structure is primarily determined by which of the following interactions: a) hydrogen bonding b) disulfide bonds c) ionic bonds d) Van der Waals attractions e)hydrophobic forces f) all of these
f) all of these
) Active M-Cdk potentiates further onset of mitosis by which functions: A) inactivation of CAK B) activation of CAK C) feedback inactivation of Cdc25 and activation of Wee1 D) feedback inactivation of Wee1 and activation of Cdc25 E) degradation of p27
feedback inactivation of Wee1 and activation of Cdc25
) Which of the following is NOT involved in Desmosome junctions? A) desmocollin B) desmoplakin C) plakophilin D) fibronectin E) plakoglobin
fibronectin
Of the following, which is the best example of a single kind of ligand that activates very similar responses in different cell types and in the same cells in distinct tissues? a) WNT b) EGF c) insulin d) epinephrine e) glucagon
glucagon
The monosaccharide that is mainly used by animals for energy transport is: a) maltose. b) lactose. c) cellulose. d) glucose. e) sucrose.
glucose
) Collagens are extremely rich in ... A) lysine and valine. B) glycine and proline. C) lysine and arginine. D) serine and threonine. E) tyrosine and phenylalanine.
glycine and proline
Which of the following is not a function of programmed cell death as mentioned in class lectures? A) elimination of infected cells. B) cancer prevention. C) prevention of autoimmunity. D) increases in organ size E) Involution after pregnancy
increases in organ size
42) Which of the following is not a modification that takes place in the golgi: a) initial creation of O-linked oligosaccharides b) Mannose 6 phosphate addition c) Tyrosine sulfation d) modification of N-linked oligosacharides e) initial creation of N-linked oligosaccharides
initial creation of N-linked oligosaccharides
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). They have the highest tensile strength
intermediate filaments
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). They tend to be more stable than the other two filaments
intermediate filaments
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). 1) These filaments are not used as tracks for motor proteins.
intermediate filaments
The energy released in the mitochondrial electron transport chain is used to transport protons where? a) into the mitochondrial matrix b) into the cytoplasm c) into the endoplasmic reticulum d) into the intermembrane space of the mitochondria e) into the thylakoid space
into the intermembrane space of the mitochondria
What characteristic of ATP synthase causes it to locate at the intersection of two membranes in the mitochondrial cristae?
it helps to establish the electrochemical gradient between the membrane
Which of the following is true about the TATA box sequence: a) it is found 30 base pairs downstream of the transcription start site. b) it is the sequence that is first distorted during transcription. c) it is recognized by TFIIB. d) it specifies the start site for translation. e) it is recognized by TFIIH.
it is the sequence that is first distorted during transcription
What kind of enzyme adds a phosphate group to another protein? A.GTPase B.kinase C.ATPase D.phosphorylase E.phosphatase
kinase
Which of the following is not a molecule that is responsible for movement along microtubles? A) kinesin-4 B) kinesin-13 C) kinesin-5 D) Dynein I E) kinesin-10
kinesin-13
Which of the following proteins is the cross shaped protein that is part of the basal lamina? A) collagen. B) syndecan. C) nidogen. D) laminin. E) periecan.
laminin
Apolipoprotein B mRNA is changed in which way to generate a shorter protein that is expressed in the intestine versus the liver? a) Exon skipping, leading to a shorter mRNA b) Alternative splice sites are joined, leading to a shorter mRNA c) mRNA editing of a single nucleotide, leading to generation of an early stop codon. d) mRNA truncation by an alternative polyadenylation site. e) IRES-dependent translation, leading to a shorter protein.
mRNA editing of a single nucleotide, leading to generation of an early stop codon
What would be the likely consequence of an mRNA that lacks SR proteins bound to it during splicing: a) the 5' cap structure would not be added b) many exons could be lost during splicing c) the mRNA would not get a poly-A tail d) poly A binding proteins would not be able to the mRNA e) hnRNPs could not bind to the intron sequences
many exons could be lost during splicing
Which amino acid will be on the tRNA that is the first to bind to the A site of the ribosome? (a) methionine (b) arginine (c) cysteine (d) valine (e) proline
methionine
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). Dyneins and kinesins walk on these
microtubules
A Rossman fold (β-α-β) is a kind of a ____. a) primary structure. b) secondary structure. c) tertiary structure. d) motif. e) domain.
motif
Which of the following myosins are the exception in terms of moving toward the plus/minus end of actin? A) myosin I B) myosin VI C) myosin VII D) myosin XI E) myosin V
myosin VI
Which of the following molecules is responsible for linking intermediate filaments between two cells in desmosome junctions? A) classical cadherins B) nonclassical cadherins C) integrins D) claudin E) occludin
nonclassical cadherins
In what way is Transcription is similar to DNA Replication? a) the same nucleotides are used for polymerization. b) an RNA transcript is synthesized discontinuously and the pieces are then joined together. c) it uses the same enzyme as that used to synthesize RNA primers during DNA replication. d) the newly synthesized RNA remains paired to the template DNA. e) nucleotide polymerization occurs only in the 5′-to-3′ direction.
nucleotide polymerization occurs only in the 5′-to-3′ direction
At the end of one set of the light cycle reactions, One ATP and one NADPH are produced. The chloroplast needs ½ additional ATP per NADPH to fix carbon. Where does the extra ATP come from? A) Anoxygenic photosynthesis B) Non-cyclic photophosphorylation C) NADPH is converted directly into ATP D) occasionally dumping electrons from complex I to plastoquinone E) the dark reactions
occasionally dumping electrons from complex I to plastoquinone
15) A function of the peroxisomes is: a) production of glucose b) it recycles old organelles c) it synthesizes fatty acids d) oxidation of fatty acids e) targeting molecules to the plasma membrane.
oxidation of fatty acids
Which of the following processes can proceed by the formation of invaginations in the plasma membrane, which then collapse, resulting in fluid uptake: a) receptor-mediated endocytosis. b) phagocytosis. c) pinocytosis. d) macropinocytosis.
pinocytosis
During DNA replication, the single-strand DNA-binding (SSB) proteins ... A. are generally found more on the leading strand than the lagging strand. B. prevent the folding of the single-stranded DNA. C. bind cooperatively to short hairpin helices that readily form in the single-stranded DNA. D. All of the above.
prevent the folding of the single-stranded
9) Aquaporin has a pair of key asparagine residues located on the wall almost halfway through its pore. These residues simultaneously bind to the oxygen atom of a passing water molecule, rendering it unavailable for hydrogen-bonding. What is the purpose for this? a) helping the channel to conduct negatively charged (but not positively charged) ions. b) preventing the channel from proton hopping. c) preventing the channel from conducting glycerol. d) preventing the channel from conducting water. e) preventing the channel from conducting glucose.
preventing the channel from proton hopping
If you were trying to create a beta turn in a protein, which amino acids would mostly likely be used?
proline and glycine
) The final product of the glycolysis reactions is: a) pyruvate b) acetyl Co-A c) glyceraldehyde 3-phosphate (G3P) d) glucose e) citrate
pyruvate
What is different in macropinocytosis and phagocytosis that distinguishes it from other enocytotic processes: a) they need clathrin b) they need dynamin c) reorganization of actin d) they bring in molecules from the outside of the cell e) they can only occur on macrophages
reorganization of actin
) In plants, production of NADPH a) occurs during the Calvin cycle. b) requires electrons originally found in water. c) occurs in the absence of light. d) happens directly after complex II is photo-excited. e) is dependent on a proton gradient.
requires electrons originally found in water
46) Normal posttranlation translocation of proteins into the lumen of the ER occurs by means of: a) sec61 b) the Get complex c) Pex 19 d) calnexin e) glucosyl tranferase
sec61
The majority of proteins belong to "protein families" that share which attribute? A. similar hydrogen bonds B. similar localization in the cell C. similar covalent modifications D. an organism/cell type of origin E. sequence patterns and therefore have similar structural domains
sequence patterns and therefore have similar structural domains
A small number of cell surface receptors can ultimately generate a large intracellular response due to activation of kinase cascades. This is best referred to as: a) signal amplification. b) signal cooperation. c) signal dampening. d) signal activation. e) signal convection.
signal amplification
Let us suppose that an autophagosome engulfs a damaged chloroplast. Before the chloroplast is delivered to be digested, how many membranes (lipid bilayers) would be separating a molecule in the thylakoid space from another molecule that is the outside of the cell? a) four b) three c) two d) five e) six
six
Which of the following biopolymers are made in dehydration reactions. a) starch b) protein c) triglycerides d) DNA e) phospholipids f) glycogen g) RNA
starch, protein, triglycerides, DNA, phospholipids, glycogen, RNA
Inside the chloroplast, where are organic molecules made? a) stroma b) on the thylakoid membrane c) between the outer and inner membranes d) inside the thylakoid e) on the cristae
stroma
The molecule that is mainly used by plants for energy transport is: a) maltose. b) lactose. c) cellulose. d) glucose. e) sucrose.
sucrose
Explain why normal primary cells taken directly from the human body have a finite lifespan when cultured in the laboratory (they stop growing after dividing a few times), and yet human cancer cells can divide in lab cultures for more than 60 years.
teleomeres shorten each cell division; cancer cells express high amounts of telomeres
) The γ-tubulin ring complex is to microtubules what ... is to actin filaments? A) fimbrin B) thymosin C) the troponin complex D) the dynactin complex E) the Arp 2/3 complex
the Arp 2/3 complex
The point of constriction on chromosomes that contains certain repeated DNA sequences that bind specific proteins is called: A) the kinetochore B) the centriole C) the cohesin complex D) the centromere E) the centrosome
the centromere
A reaction will always occur spontaneously if: A) the change in Enthalpy (DH) is < 0 B) the change in Enthalpy (DH) is > 0 C) the change in Gibb's free energy (DG) is < 0 D) the change in Gibb's free energy (DG) is > 0 E) the change in Entropy (DS) is < 0
the change in Gibb's free energy (DG) is < 0
26) Which of the following resembles a soccer ball made up of 3-armed triskellion proteins: a) a dynamin oligomer. b) the outer COPI coat. c) the outer COPII coat. d) a BAR domain. e) the outer clathrin coat.
the outer clathrin coat
3) Porin proteins form large, barrel-like channels in the membrane. Which of the following is not true about these channels? a) They are made primarily of β sheets. b) They are made primarily of α helices. c) They cannot form narrow channels. d) They have alternating hydrophobic and hydrophilic amino acids. e) They are transmembrane proteins
they are made primarily of α helices
Initiator and executioner caspases share all of the following features EXCEPT that ... A) they have a small and large subunit. B) they cleave proteins after aspartic acid residues. C) they have large prodomains. D) they undergo cleavage during activation. E) they are cysteine proteases (they have a cysteine residue at their active site)
they have large prodomains
Which is not true about carbon-carbon double bonds in phospholipids? a) they are largely found in the fatty acid tails of phospholipids. b) they make kinks in the tail. c) double bonds make the phospholipids more "unsaturated". d) they make the melting temperature higher. e) they prevent the fatty acid chains from getting as close to each other as they normally when there is a single bond
they make the melting temperature higher
91) Your friend works in a biotechnology company and has discovered a drug that blocks the ability of Ran to exchange GDP for GTP. What is the most likely effect(s) of this drug on nuclear transport? (a) Nuclear export receptors would be unable to bind cargo. (b) Nuclear import receptors would be unable to enter the nucleus. (c) Nuclear import receptors would be unable to release their cargo in the nucleus. (d) Nuclear export receptors would interact irreversibly with the nuclear pore fibrils. (e) Nuclear import receptors would be unable to bind their cargo in the cytoplasm.
(a) Nuclear export receptors would be unable to bind cargo. (c) Nuclear import receptors would be unable to release their cargo in the nucleus.
What are the net products of glycolysis per molecule of glucose: A) 4 ATP, 2 NADH, 2 Pyruvate B) 2 ATP, 2 NADH, 1 Pyruvate C) 2 ATP, 2 NADH, 2 Pyruvate D) 2 ATP, 4 NADH, 1 Pyruvate E) 2 ATP, 4 NADH, 2 Pyruvate
2 ATP, 2 NADH, 2 Pyruvate
How many unique tripeptides (three amino acids hooked together) are there?
8000
Dan has discovered a new organism that utilizes a single stranded DNA molecule for its genome. He believes that during differentiation of some of the organism's cells that its DNA is edited to remove some internal sequences. He tells Mary that he hypothesizes that the DNA splicing in this case occurs similar to eukaryotic mRNA splicing. She tells him that it is not likely that this is the case. Which of the following are valid and RELEVANT reasons why she believes that this is not the case: A) She has observed by electron microscopes and proved that there are no lariat-like structures in these cells. B) The organism does not have a DNA equivalent of snRNPs. C) The organism has no snoRNPs that recognize sites to make modified nucleotides. D) DNA can only form a double helix; it can't form other secondary structures, even if it is single stranded. E) DNA contains deoxyribose; there is no 2' hydroxyl group. F) There are no UPF proteins in the organism. G) She has sequenced the genome and there are no AG sequences in the genome. H) all of the above are valid reasons why this organisms DNA splicing can't occur like eukaryotic mRNA splicing.
A) She has observed by electron microscopes and proved that there are no lariat-like structures in these cells B) The organism does not have a DNA equivalent of snRNPs E) DNA contains deoxyribose; there is no 2' hydroxyl group G) She has sequenced the genome and there are no AG sequences in the genome
Integrins are part of what anchoring junctions? a) Adherens junctions and desmosomes b) Actin-linked cell-matrix junction and Hemidesmosome c) Actin-linked cell-matrix junctions and Desmosomes d) Adherens junctions and Hemidesmosome e) Tight junctions
Actin-linked cell-matrix junction and Hemidesmosome
Which of the following events normally activates a GTP-binding protein? a) GTP hydrolysis by the protein b) Pi release after GTP hydrolysis c) Activation of an upstream GTPase-activating protein d) Activation of an upstream guanine nucleotide exchange factor e) Phosphorylation of a bound GDP molecule by an upstream phosphorylase
Activation of an upstream guanine nucleotide exchange factor
Which of the following proteins contains a BH4 domain and therefore prevents cell death? A) Puma. B) BCL2 C) Bad D) Bak E) Bax
BCL2
Plastocyanin is structurally and functionally similar to which of the proteins in the mitochondrial electron-transport chain? a) Cytochrome c b) ubiquinone c) Succinate dehydrogenase (complex II) d) NADH e) Cytochrome c reductase (complex III)
Cytochrome c
The cytochrome b6-f complex that transfers electrons between the two photosystems in photosynthesis is structurally and functionally similar to which of the complexes in the mitochondrial electron-transport chain? a) ATP synthase b) NADH dehydrogenase (complex I) c) Succinate dehydrogenase (complex II) d) Cytochrome c reductase (complex III) e) Cytochrome c oxidase (complex IV)
Cytochrome c reductase (complex III)
What is (are) true about photosystems I and II? a) Both contain a reaction center composed of chlorophyll a. b) Both involve the splitting of water to donate an electron to the reaction center. c) Both lose an electron to a primary electron acceptor that passes the electron down an electron transport chain. d) Both lead to the direct generation of oxygen. e) Both are found in the stroma f) Photosystem I is primarly responsible for ATP generation, Photosystem II is primarily responsible for NADPH synthesis. g) Photosystem II is primarly responsible for ATP generation, Photosystem I is primarily responsible for NADPH synthesis.
a) Both contain a reaction center composed of chlorophyll a. c) Both lose an electron to a primary electron acceptor that passes the electron down an electron transport chain. g) Photosystem II is primarly responsible for ATP generation, Photosystem I is primarily responsible for NADPH synthesis.
97) Which of the following are correct regarding cholesterol? a) It is hydrophobic on one end and hydrophilic on the other. b) It is a sterol. c) It makes the membrane less permeable to small hydrophilic molecules. d) It is not as long as a typical phospholipid. e) It affects the fluidity of the lipid bilayer.
a) It is hydrophobic on one end and hydrophilic on the other. b) It is a sterol. c) It makes the membrane less permeable to small hydrophilic molecules. d) It is not as long as a typical phospholipid. e) It affects the fluidity of the lipid bilayer.
93) Which of the following is directly involved in driving protein import into the mitochondrial matrix space? a) Membrane potential across the inner membrane b) Membrane potential across the outer membrane c) GTP hydrolysis inside mitochondria d) GTP hydrolysis outside mitochondria e) ATP hydrolysis inside mitochondria f) ATP hydrolysis outside mitochondria g) Light
a) Membrane potential across the inner membrane e) ATP hydrolysis inside mitochondria f) ATP hydrolysis outside mitochondria
96) Through multiple routes, which of the following can play roles in getting protein integrated into the intermembrane space and the inner mitochondrial membrane? a) Mia40 b) TOM complex c) TIM 22 d) TIM 23 e) TOCs f) TICs g) OXA h) intermembrane chaperones i) SAM j) BAM
a) Mia40 b) TOM complex c) TIM 22 d) TIM 23 h) intermembrane chaperones
Which of the following component(s) of the electron-transport chain are actual proton pumps that translocate to the intermembrane space of the mitochondria ? (clarification: in this case, you should not include the complex that helps a small molecule to dump its protons once or more, since this would not be considered a direct proton pump) a) NADH dehydrogenase (complex I) b) succinate dehydrogenase (complex II) c) cytochrome c reductase (complex III) d) cytochrome c oxidase (complex IV) e) ATP synthase
a) NADH dehydrogenase (complex I) d) cytochrome c oxidase (complex IV)
Which of the following are small G proteins? a) RAS b) RAB c) RAN d) RHEB e) RAT f) Gα g) RAG
a) RAS b) RAB c) RAN d) RHEB
Which of the following are electron carriers or functional groups that conduct electrons in (or between) the electron-transport chain complexes in mitochondria? a) cytochrome c b) biotin c) plastiquinone d) copper ion e) aconitase f) rhodopsin g) iron- sulfur clusters h) ubisemiquinone i) plastocyannin j) ubiquinol k) heme group l) FMN
a) cytochrome c d) copper ion g) iron- sulfur clusters h) ubisemiquinone j) ubiquinol k) heme group l) FMN
What of the fate of mature mRNA in eukaryotes that has a premature stop codon 5' to EJC proteins bound to it in the cytoplasm: a) it has previously been given a 5' cap in the nucleus b) it has previously been given a poly-A tail in the nucleus c) It is translated d) It is not translated e) It is degraded f) It is bound in complex with Upf proteins
a) it has previously been given a 5' cap in the nucleus b) it has previously been given a poly-A tail in the nucleus d) It is not translated e) It is degraded f) It is bound in complex with Upf proteins
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). Myosins bind to these.
actin filaments
Indicate if each of the following is true or representative of actin filaments (A), microtubules (B), or intermediate filaments (C). Largely form the cortical cytoskeleton
actin filaments
90) Which of the following statements accurately describes the events involved in the propagation of an action potential? a) Ca2+ channels repolarize the membrane. b) Local depolarization causes nearby Na+ channels to open. c) the action potential can move backward. d) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is reestablished. e) The outflow of K+ through voltage-gated K+ channels helps bring the membrane back to its resting potential. f) The ions associated with membrane potential are typically located very close to the inside and outside of the membrane. g) An initial influx of Na+ through a small cluster of channels causes local depolarization of the membrane.
b) Local depolarization causes nearby Na+ channels to open. d) Channels in depolarized regions of the membrane are inactivated until the resting membrane potential is reestablished. e) The outflow of K+ through voltage-gated K+ channels helps bring the membrane back to its resting potential. f) The ions associated with membrane potential are typically located very close to the inside and outside of the membrane. g) An initial influx of Na+ through a small cluster of channels causes local depolarization of the membrane.
What is true about how NADH and FADH2 donate electrons to the electron transport chain? a) NADH is oxidized and FADH2 is reduced. b) NADH contributes its electrons to the first transmembrane complex in the electron transport chain and FADH2 contributes its electrons after the first transmembrane complex. c) More protons are transported into the intermembrane space of the mitochondria in response to one molecule of NADH as compared to the number of protons transported in response to one molecule of FADH2. d) The electrons from NADH and FADH2 both ultimately end up reducing oxygen to generate water. e) The electrons from FADH2 only come from the Kreb's (citric acid) cycle, while the electrons in NADH may come from Glycolysis and pyruvate oxidation as well.
b) NADH contributes its electrons to the first transmembrane complex in the electron transport chain and FADH2 contributes its electrons after the first transmembrane complex. c) More protons are transported into the intermembrane space of the mitochondria in response to one molecule of NADH as compared to the number of protons transported in response to one molecule of FADH2. d) The electrons from NADH and FADH2 both ultimately end up reducing oxygen to generate water. e) The electrons from FADH2 only come from the Kreb's (citric acid) cycle, while the electrons in NADH may come from Glycolysis and pyruvate oxidation as well.
98) Which of the following are responsible for identifying which target membranes a transport vesicle should be targeted to? a) Ras b) Rab(s) c) Ran d) adaptor proteins (adaptins). e) phosphoinositides f) phosphoproteins g) DAG
b) Rab(s) e) phosphoinositides
99) Which of the following are involved in protein folding (and its recognition) within the ER: a) N-glycanase b) calnexin c) glucosyl transferase d) glucosidase e) GTP f) glucose attachment on the protein
b) calnexin c) glucosyl transferase d) glucosidase f) glucose attachment on the protein
Which of the following mechanism(s) explain how the presence of iron is regulated by ferritin/transferrin expression: a) in the presence of iron, the Fenton reaction produces superoxide, which acts as a transcriptional activator to drive transcription of the Ferritin gene. b) in the absence of Iron, aconitase binds to a hairpin that stabilizes the transferrin mRNA expression. c) in the presence of iron, the transferrin mRNA is oxidized by the Fenton reaction conversion of hydroxides. d) In the presence of iron, iron binds to cis aconitase and causes it to fall off of the 3' end of the transferrin mRNA, allowing transferrin to be degraded. e) in the absence of Iron, aconitase binds to a hairpin that blocks ferritin expression. f) in the presence of iron, cis aconitase falls off of the 5' end of the ferritin mRNA, allowing the ferritin mRNA to be expressed. g) all of the above
b) in the absence of Iron, aconitase binds to a hairpin that stabilizes the transferrin mRNA expression d) In the presence of iron, iron binds to cis aconitase and causes it to fall off of the 3' end of the transferrin mRNA, allowing transferrin to be degraded e) in the absence of Iron, aconitase binds to a hairpin that blocks ferritin expression f) in the presence of iron, cis aconitase falls off of the 5' end of the ferritin mRNA, allowing the ferritin mRNA to be expressed
Circle the following descriptions which better apply to the light reactions in plant chloroplasts rather than the dark reactions. a) production of the sugar glyceraldehyde 3-phosphate. b) the electron-transfer chain embedded in the thylakoid membrane. c) generation of NADPH. d) fixation of CO2. e) generation of ATP. f) It involves O2 production. g) uses the enzyme Rubisco
b) the electron-transfer chain embedded in the thylakoid membrane. c) generation of NADPH. d) fixation of CO2. e) generation of ATP. f) It involves O2 production.
At what checkpoint(s) does the cell arrest in response to DNA damage? A) only G1/S B) only G2/M C) only spindle D) both G2/M and spindle E) both G1/S and G2/M
both G1/S and G2/M
p27 and p21 CKIs inhibit which of the following cyclin/Cdk complexes: A) only S-Cdk B) only G1/S-Cdk C) only M-Cdk D) both G1/S-Cdk and S-Cdk E) both G1/S-Cdk and M-Cdk
both G1/S-Cdk and S-Cdk
In the active state of the integrin dimer, ... A) both intracellular and extracellular binding sites are inaccessible. B) the intracellular binding sites are inaccessible, while the extracellular binding sites are exposed. C) the intracellular binding sites are exposed, while the extracellular binding sites are inaccessible. D) both intracellular and extracellular binding sites are exposed.
both intracellular and extracellular binding sites are exposed
Which of the following are the primary target(s) for antibiotic drugs that target bacteria? a) synthesis of peptidoglycan chains in bacterial cell walls only b) prokaryotic translation machinery only d) both synthesis of peptidoglycan chains in bacterial cell walls and prokaryotic translation machinery e) prokaryotic transcription machinery only c) both synthesis of peptidoglycan chains in bacterial cell walls and prokaryotic transcription machinery
both synthesis of peptidoglycan chains in bacterial cell walls and prokaryotic translation machinery
95) Which of the following is involved in getting soluble proteins into the mitochondrial matrix? a) TOCs b) TICs c) mitochondrial targeting sequence d) TOMs e) TIMs f) hsp70 g) SAM h) OXA i)all of these
c) mitochondrial targeting sequence d) TOMs e) TIMs f) hsp70
Which of the following carry electrons twice during a single electron transport cycle in the mitochondria OR a single electron transport cycle in photosynthesis ? FINAL:THIS QUESTION WILL BE REVISED for clarity to talk about Q-type cycles: so only G and C will be correct. As is it currently written c, d, and g would be considered correct, with a and h being acceptable a) cytochrome c b) biotin c) plastiquinone d) ferredoxin e) aconitase f) rhodopsin g) ubiquinone h) plastocyannin
c) plastiquinone g) ubiquinone
Which of the following molecules or functional groups carry electrons during the process of photosynthesis? a) cytochrome c b) biotin c) plastiquinone d) ferredoxin e) aconitase f) rhodopsin g) ubiquinone h) ubisemiquinone i) plastocyannin j) ubiquinol k) FADH2
c) plastiquinone d) ferredoxin i) plastocyannin k) FADH2
Which type of lipids are the most abundant in the plasma membrane? a) triacylglycerides b) phospholipids c) sphingolipids d) glycolipids e) proteolipids
phospholipids
Name 5 second messengers that function downstream of G protein-coupled receptors (GPCR).
cAMP DAG IP3 Ca2+ Nitric oxide
2) Which of the following protein families are not involved in getting vesicles fused with their target membrane? a) v-SNAREs b) Rabs c) tethering proteins d) coat proteins e) v-SNAREs
coat proteins
What is the purpose for having vesicles inside what us designated the multivesicular body (NOT the recycling endosome): a) modification with Mannose 6 phosphate b) complete digestion of lipids and membrane proteins in the lysosome c) exocytosis d). return of receptors to the plasma membrane e) modification of N-linked oligosacharides
complete digestion of lipids and membrane proteins in the lysosome
What is similar about G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs)? a) Both are activated by autophosphorylation. b) Both bind to primarily hydrophobic ligands. c) Both have similar extracellular domains. d) They both activate multiple signaling events e) Both can activate G proteins (through different kinds).
d) They both activate multiple signaling events e) Both can activate G proteins (through different kinds).
Although both are receptor tyrosine kinases, how is the activation of epidermal growth factor receptor (EGFR) different from that of insulin receptor (IR)? Two are correct a) EGFR is a dimer in its inactive and active forms, whereas IR dimerizes only when active. b) EGFR activation requires dimerization, whereas IR can become activated as a monomer. c) EGFR is activated by transautophosphorylation, whereas IR activation is phosphorylation-independent and is a simple consequence of receptor dimerization. d) Unlike IR activation, EGFR activation involves a different asymmetrical arrangement of the intracellular kinase domains. e) EGFR is not activated by transautophosphorylation, whereas IR activation is activated by transautophosphorylation.
d) Unlike IR activation, EGFR activation involves a different asymmetrical arrangement of the intracellular kinase domains. e) EGFR is not activated by transautophosphorylation, whereas IR activation is activated by transautophosphorylation.
Which of the following affect the ability of histone "writers" and "readers" to affect gene expression: a) monomethylation of arginine residues in histone tails b) dimethylation of arginine residues in histone tails c) trimethylation of arginine residues in histone tails d) monomethylation of lysine residues in histone tails e) dimethylation of lysine residues in histone tails f) trimethylation of lysine residues in histone tails g) modification of histone tails by lysine acetylation h) kinase phosphorylation of serine in histone tails i) all of the above
d) monomethylation of lysine residues in histone tails e) dimethylation of lysine residues in histone tails f) trimethylation of lysine residues in histone tails g) modification of histone tails by lysine acetylation h) kinase phosphorylation of serine in histone tails
Stable hydrogen bonding occurs with hydrogens that are bonded to: a) phosphorous b) carbon c) sulfur d) oxygen e) nitrogen f) fluorine g) all of the previous
d) oxygen e) nitrogen f) fluorine
What would be the likely consequence of an mRNA that does not get CPSF or CstF factors bound to the nascent mRNA: a) hnRNPs could not bind to the intron sequences b) the 5' cap structure would not be added c) many exons would be lost during splicing d) poly A binding proteins would not bind to the mRNA e) the mRNA would not get a poly-A tail
d) poly A binding proteins would not bind to the mRNA e) the mRNA would not get a poly-A tail
13) Glucose trimming and re-adding the glucose back on the oligosacharride in the ER is for what purpose? a) binding to coat proteins. b) transport to the golgi from the ER. c) designating whether a protein is folded properly. d) designating how long the protein has been in the ER. e) designating whether a protein needs to be secreted outside the cell.
designating whether a protein is folded properly
Phosphofructokinase, an early enzyme in glycolysis (the process in which glucose is broken down to harvest its energy into ATP), is inhibited by a number of factors, including high levels of ATP, which binds at a site distinct from the active site. This is an example of: A) cofactor binding B) allosteric activation C) feedback inhibition D) competitive inhibition E) catalysis
feedback inhibition
Which of the following statements is true about mRNA in prokaryotes: a) The 5' end has a 7-methylguanylate cap. b) The 3' end has a poly-A tail. c) its synthesis requires the sigma factor. d) introns must be removed before translation. e) mRNAs can only encode one protein.
its synthesis requires the sigma factor
Which of the following might decrease the transcription of only one specific gene in a eukaryotic cell? a) a decrease in the amount of TFIID b) mutations that introduced a few stop codons into transcribed DNA that precedes the gene's coding sequence c) mutations that introduced extensive sequence changes into the DNA that precedes the gene's transcription start site d) a decrease in the amount of RNA polymerase II e) a decrease in the amount of RNA polymerase III
mutations that introduced extensive sequence changes into the DNA that precedes the gene's transcription start site
37) The presence of which type of lipid explains why the inner plasma membrane has a slight negative charge: a) phosphatidylcholine b) phosphatidylserine c) phosphatidylethanolamine d) phophatidyinositol e) triacylglycerides
phosphatidylserine
18) Which of the following is a main function of glycolipids on the surface of all eukaryotic plasma membranes: a) acts enzymatically to cleave extracellular matrix proteins b) prevents the immune cells from destroying the cell c) controls the lifespan of a plasmid membrane protein d) opens the membrane for endocytosis
prevents the immune cells from destroying the cell
During this stage of mitosis, the chromosomes become attached to the spindle at their kinetochores. A) prophase B) prometaphase C) metaphase D) anaphase E) telophase
prometaphase
During this stage of mitosis, the spindle begins to form and the nuclear envelope begins to break down (end of this stage). A) anaphase B) metaphase C) prophase D) telophase E) prometaphase
prophase
Which of the following is NOT part of the large eukaryotic complex that mediates transcription: a) the Mediator complex proteins b) transcriptional activators or repressors bound to enhancer sequences c) proteins bound to the Kozak consensus sequence d) TFIID bound to the TATA box e) the chromatin remodeling complex f) histone modifying enzymes
proteins bound to the Kozak consensus sequence
89) Name 5 ways (modifications or interactions) by which membrane proteins are made to associate with the plasma membrane? Note: I mentioned 7 in class. Do not refer to signaling pathways, do not indicate vesicles or other ways that the proteins get to the membrane. I want to know how they are associated in/with the membrane once they are there.
single pass transmembrane protein multipass transmembrane protein GPi Lipid modifications Hydrophobic beta barrels
Which proteins binds to the splice junction sites and catalyze mRNA splicing? A. snRNPs.B. hnRNPs.C. SR proteins.D. EJC proteins.E. snoRNAs.
snRNPs
6) Signal sequences that direct proteins to the correct compartment are _________. a) added to proteins through post-translational modification. b) always at the N terminus of the protein. c) added to a protein by a protein translocator. d) sometimes removed once a protein is at the correct destination. e) always positively or negatively charged.
sometimes removed once a protein is at the correct destination
Which of the following protein complexes is actually an enzyme in the Kreb's cycle? a) NADH dehydrogenase (complex I) b) succinate dehydrogenase (complex II) c) cytochrome c reductase (complex III) d) cytochrome c oxidase (complex IV) e) ATP synthase
succinate dehydrogenase (complex II)
4) Membrane lipids are capable of many different types of movement. Which of these does not occur spontaneously in biological membranes? a) rotation b) lateral movement c) switching between inner and outer leaflets d) packing in cholesterol-enriched lipid rafts e) flexing of hydrocarbon chains
switching between inner and outer leaflets
Prokaryotes have chromosomes that are circular in structure. Which of the following would such chromosomes lack?a) sugar-phosphate backbone b) replication origin c) complementary base pairs d) telomeres e) DNA double helix
telomeres
This stage of mitosis is characterized by the disassembly of spindle apparatus, the reestablishment of the nuclear membrane, and the decondensation of the chromosomes A) prometaphase B) metaphase C) anaphase D) telophase E) prophase
telophase
31) A potassium channel conducts K+ ions several orders of magnitude better than Na+ ions, because ... a) the Na+ ion is too large to pass through the channel pore. b) the hydrated Na+ ion occupies a larger volume compared to the hydrated K+ ion, and is too large to pass through the channel pore. c) the Na+ ion binds too tightly to to the carbonyls in the channel pore. d) the asparagine residues in the channel cannot bind to Na+. e) the K+ ion is the right size to interact with carbonyls in the channel in a way such that it is energetically favorable to lose its large solvent shell.
the K+ ion is the right size to interact with carbonyls in the channel in a way such that it is energetically favorable to lose its large solvent shell
20) Glucose in our diet are absorbed via the transcellular transport pathway by the intestinal epithelial cells. This process requires ATP hydrolysis by ... a) the Na+-glucose symporters in the apical(lumen) domain of the plasma membrane. b) the Na+-glucose antiporters in the apical (lumen) domain of the plasma membrane. c) the glucose carriers in the basal (extracellular fluid) domain of the plasma membrane. d) the Na+-K+ pumps in the plasma membrane. e) F-type ATPases in the apical (lumen) domain of the plasma membrane
the Na+-K+ pumps in the plasma membrane
You have a segment of DNA that contains the following sequence: 5′-GGACTAGACAATAGGGACCTAGAGATTCCGAAA-3′ 3′-CCTGATCTGTTATCCCTGGATCTCTAAGGCTTT-5′ You know that the RNA transcribed from this segment contains the following sequence: 5′-GGACUAGACAAUAGGGACCUAGAGAUUCCGAAA-3′ Which of the following choices best describes how transcription occurs? (a) the top strand is the template strand; RNA polymerase moves (relative to this strand) from 5′ to 3′ (b) the top strand is the template strand; RNA polymerase moves (relative to this strand)from 3′ to 5′ (c) the bottom strand is the template strand; RNA polymerase moves (relative to this strand) from 5′ to 3′ (d) the bottom strand is the template strand; RNA polymerase moves (relative to this strand) from 3′ to 5′
the bottom strand is the template strand; RNA polymerase moves (relative to this strand) from 3′ to 5′
How is cholesterol biosynthesis controlled by transcription factor Sterol Response Binding Protein (SReBP)? a) nuclear import is controlled by phosphorylation in the presence of low cholesterol. b) a nuclear import sequence is masked by binding to another protein in the presence of low cholesterol, which is removed, allowing it to translocate to the nucleus. c) the SCAP protein retains SReBP in the presence of low cholesterol. d) the factor goes to the Golgi in presence of low cholesterol, where it is proteolytically cleaved, allowing it to translocate to the nucleus. e) the SCAP protein modifies SReBP in the presence of low cholesterol with a nuclear import signal.
the factor goes to the Golgi in presence of low cholesterol, where it is proteolytically cleaved, allowing it to translocate to the nucleus
The photosynthetic electron transport causes the accumulation of protons in which part of the chloroplast? a) matrix b) in between the outer membrane and the inner membrane c) thylakoid space d) outside the outer membrane e) stroma
thylakoid space
Stathmin has a function with regard to tubulins that is similar to how this protein functions with actin subunits: a) cofilin b) thymosin c) formins d) profilin e) myosins
thymosin
A particular reaction has a negative DG. However, this reaction takes years to proceed without an enzyme. Why is this the case? A) This reaction does not proceed spontaneously B) This reaction does not obey the second law of thermodynamics. C) The initial free energy of the reactants is much less than the final free energy of the products. D) A certain amount of activation energy is required for the reaction to proceed. E) The presence of an enzyme changes the equilibrium constant for the reaction.
A certain amount of activation energy is required for the reaction to proceed
Which is the enzyme that always keeps DNA negatively supercoiled in bacteria a) DNA helicase b) DNA topoisomerase I c) DNA topoisomerase 1I d) DNA primase e) DNA gyrase
DNA gyrase
Which enzyme synthesizes short RNA segments on the lagging strand that are then extended before ultimately being removed? A. DNA helicase. B. DNA polymerase. C. DNA primase. D. DNA ligase. E. Telomerase.
DNA primase
Which of the following statements about the genetic code is correct? a) All codons specify more than one amino acid. b) All amino acids are specified by more than one codon. c) All codons specify an amino acid. d) The genetic code is redundant (degenerate), meaning that different codons can lead to insertion of the same amino acid. e) The code is very different between organisms.
The genetic code is redundant (degenerate), meaning that different codons can lead to insertion of the same amino acid
Which of the following is true about enzymes: a) enzymes help a reaction proceed by stabilizing the transition state of a reactant. b) enzymes can lower the activation energy of a reaction. c) enzymes change the equilibrium constant of a reaction. d) enzymes speed up the kinetics of a reaction e) enzymes reduce the total energy difference (DG of a reaction). f) most biological enzymes are proteins. g) all of the above are true
a) enzymes help a reaction proceed by stabilizing the transition state of a reactant b) enzymes can lower the activation energy of a reaction d) enzymes speed up the kinetics of a reaction f) most biological enzymes are proteins
Which of the following sequences are bound by the general transcription factor TFIID? a) The Kozak's consensus sequence b) The Shine-Dalgarno sequence c) The BRE d) The TATA Box e) The MTE f) The DPE g) The INR h) all of the above
d) The TATA Box e) The MTE f) The DPE g) The INR
Which of the following is true about small G proteins, such as Ras: a) they are more active when bound to ATP. b) they are less active when bound to ATP. c) they are more active when bound to GDP. d) they are more active when bound to GTP. e) they are made more active by GEF proteins f) they are made less active by GEF proteins g) they are made more active by GAP proteins. h) they are made less active by GAP proteins.
d) they are more active when bound to GTP e) they are made more active by GEF proteins h) they are made less active by GAP proteins
Water molecules are polar with ends that exhibit partial positive and negative charges. These opposite charges allow water molecules to attract each other through a) covalent bonds. b) ionic bonds. c) hydrophobic forces d) Van der Waals interactions. e) hydrogen bonds
hydrogen bonds
What would happen if you created a tRNA with an anticodon of 5-GAA-3 that is charged with methionine, and added this modified tRNA to a cell-free translation system that has all the normal components required for translating RNAs? (a) leucine would be incorporated into proteins at some positions where methionine should be (b) methionine would be incorporated into proteins at some positions where phenylalanine should be (c) methionine would be incorporated into proteins at some positions where leucine should be (c) phenylalanine would be incorporated into proteins at some positions where methionine should be (e) methionine would be incorporated into proteins at some positions where glutamine should be
methionine would be incorporated into proteins at some positions where phenylalanine should be
Biological membranes contain bilayers that are mostly made of ______. a) oils. b) phospholipids. c) prostaglandins. d) cholesterol e) triglycerides
phospholipids
