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Scurvy is a disease that is caused by a lack of Vitamin C, which is a cofactor for the enzyme that converts proline to hydroxyproline in fibrillar collagens. How would collagen be impacted by having decreased amounts of hydroxyproline? Collagen would not have hydrogen bonding to hold the triple helices together The collagen would not bind calcium salts to form bone The monomers would not fold into alpha helices The alpha helices would have bulky side chains that would prevent packing together Collagen would not be secreted from cells - Correct Answer Collagen would not have hydrogen bonding to hold the triple helices together The enzymes that are necessary to build oligosaccharide chains for protein glycosylation are called Glycotransferases Dolichol Acetyltransferases Translocons Signal peptidases - Correct Answer Glycotransferases What role do repeating leucine residues have in the function of leucine zipper transcription factors? They mediate binding of two monomers to form a dimer They mediate DNA binding They activate RNA polymerase They serve as a binding platform for transcriptional activators They are part of the nuclear localization signal - Correct Answer They mediate binding of two monomers to form a dimer

You are examining the chromosomes in cells from a female human under the microscope. You can see that one of the X chromosomes appears very small and condensed compared the other X chromosome and compared to the autosomes. This small, condensed X chromosome would be expected to have the following epigenetic changes: DNA methylation and dense heterochromatin Predominantly euchromatin and highly acetylated H3K Lack of histones in the nucleosomes Permanent interactions of TBP with DNA Strong association with RNA polymerase - Correct Answer DNA methylation and dense heterochromatin You are creating a transgenic zebrafish line and want to visualize cells that express the transcription factor SPI1, because you are interested in macrophages. You want to do this by making SPI1-expressing cells (macrophages) "glow" with Green Fluorescent Protein. How could you do this? Create a DNA transgene in which the promoter of SPI1 is upstream of GFP coding sequence Create a DNA transgene that carries the promoter region of the GFP gene Inject mRNA with GFP coding sequence into the zebrafish embryo at the single cell stage Inject GFP protein into the embryo which will localize only to macrophages Perform a microarray of zebrafish macrophages and examine the microarray chip for GFP mRNA - Correct Answer Create a DNA transgene in which the promoter of SPI1 is upstream of GFP coding sequence You are studying adhesion of cells to each other and to the extracellular matrix. You are working with epithelial cells that have adhered to a basement membrane on a petri dish and to form sheets, and the cells adhere laterally to each other. You want to disrupt the attachment of the epithelial cells to the basement membrane AND to each other, but you can only use one reagent to do so. Which of the following reagents would you select for this purpose? Trypsin Neuraminidase DNAse

Collagenase RNAse - Correct Answer Trypsin What gives rough ER the "rough" appearance in electron micrographs? active ribosomes associated with the membrane glycosylation of phospholipids in the membrane phosphorylation of phospholipids in the membrane high levels of phosphatidylcholine in the membrane high levels of sphingomyelin in the membrane - Correct Answer active ribosomes associated with the membrane You are studying a new protein and trying to determine where it localizes after expression. You suspect it is secreted from the cell. What feature in the mRNA could best help you determine if the protein may be secreted from the cell? Presence of a signal sequence at the N terminus Presence of a signal sequence at the C terminus Hydrophobic stretch of amino acids High abundance of Asparagine residues Acetylation of Lysine residues - Correct Answer Presence of a signal sequence at the N terminus The inactive mRNAs that are stored in an egg prior to fertilization are prevented from translation by Binding of factors to the UTRs of maternally provided mRNAs Transcription factors binding to the 5'UTR the maternally provided mRNAs Methylation of H3K9 associated with these maternally provided mRNAs Constant localization of the mRNAs to the P-bodies The presence of long polyA tails at the 3' end - Correct Answer Binding of factors to the UTRs of maternally provided mRNAs

Which of the following best describes adherins junctions? Homotypic or heterotypic interactions of cadherins between cells Connection of integrins on one cell to laminins on another cell Continuous actin filaments tethering cells together Aligned channels that allow diffusion of molecules between cells Collagen networks connecting to laminin networks to anchor cells - Correct Answer Homotypic or heterotypic interactions of cadherins between cells Which of the following polypeptides would be expected to lack a signal peptide (Select ALL that are correct) ribosomal proteins Collagen integrin beta subunit actin binding proteins cytokine transcription factor - Correct Answer ribosomal proteins actin binding proteins transcription factor You want to determine where and when gene X is expressed during development of a tadpole. What would you do? Choose the best answer for your experimental questions. Clone the green fluorescent protein gene downstream of gene X's promoter, transfer it into a single-celled embryo and monitor fluorescence through-out the stages of development. Inject the nucleus from an adult frog into a fertilized egg and sequence the resulting tadpole mRNA to see if gene X is expressed. Extract DNA from whole embryos at various developmental stages and check for expression of gene X on a microarray. Delete the TATA box region of gene X's promoter and sequence mRNA at various stages to see if gene X is expressed.

Extract DNA at various developmental stages, incubate it with transcription factors that promote expression of gene X, and do a DNA footprinting analysis. - Correct Answer Clone the green fluorescent protein gene downstream of gene X's promoter, transfer it into a single-celled embryo and monitor fluorescence through-out the stages of development. Docking, or tethering, of vesicles at their destination membrane is regulated by which class of molecules? RabGTPases Cadherins Integrins Histone Acetylases Clathrin - Correct Answer RabGTPases You are creating a transgenic zebrafish line and want to visualize cells that express the transcription factor SPI1, because you are interested in macrophages. You want to do this by making SPI1-expressing cells (macrophages) "glow" with Green Fluorescent Protein. You want to ensure that GFP, when expressed in the cells, remains in the cytosol and is not secreted from the cells. How do you design the coding sequence of GFP to ensure this? Do not include a signal peptide sequence in the GFP coding sequence Include a signal sequence at the 5' end of the GFP coding sequence Include a sequence that codes for a hydrophobic segment Include a sequence that localizes GFP to COPII vesicles Include codons for Asparagine (Asn) at the N-terminus - Correct Answer Do not include a signal peptide sequence in the GFP coding sequence You have three homogenized samples prepared from membrane preparations from ER, Golgi, and Plasma Membrane, and you need to figure out which sample is from which organelle. You could do this by Examining the abundance of different phospholipid types in the samples Determining whether or not the samples contain phosphatidylcholine Determining whether or not the samples contain phospholipids

Examining the types of transcription factors present in the samples Determining whether or not the samples contain RabGTPases - Correct Answer Examining the abundance of different phospholipid types in the samples Transcription factors interact with DNA through _______. Noncovalent interactions Covalent interactions A combination of covalent and noncovalent interactions Either covalent or noncovalent interactions, depending on the transcription factor Covalent linkage to chromatin - Correct Answer Noncovalent interactions Transcription factors interact with DNA by Binding to the major groove of the double helix Binding to the minor groove of the double helix Acetylating residues on histone tails Binding to the 5' cap of the gene Bridging the DNA with ribosomes for expression - Correct Answer Binding to the major groove of the double helix A major way in which gene expression is controlled after synthesis of the protein product is Poly-ubiquitination and targeting to the proteasome Inhibitory binding of factors to the 3' and 5' UTR Binding of transcriptional repressors Translation via ribosomes associated with ER Length of the polyA tail - Correct Answer Poly-ubiquitination and targeting to the proteasome

You are interested in an uncharacterized gene, and there is some evidence that it encodes a protein that may act as a transcription factor. Which of the following would provide further evidence that this is the case? (Select ALL that are true) Dimerizes Has an alpha-helical domain that can bind DNA Localizes to the nucleus Has a signal sequence at the N-terminus Is an integral membrane protein - Correct Answer Dimerizes Has an alpha-helical domain that can bind DNA Localizes to the nucleus You are studying a glycoprotein that has oligosaccharide chains using sialic acid as the terminal sugars. In which cellular compartment are the sialic acid residues added to the glycoprotein? Trans Golgi ER Cis Golgi Vesicles Endosomes - Correct Answer Trans Golgi Suppose you are interested in the transcription factor SPI1, which is known to drive differentiation of macrophages (a type of white blood cell) in humans. You want to investigate the way in which SPI1 regulates gene expression, and you are using a human macrophage cell line to perform your research. What kind of experiment could you do to directly show that SPI1 binds to DNA in the promoter region of genes expressed in macrophages? Chromosome Immunoprecipitation DNA Footprinting Microarray RNA Sequencing In situ Hybridization - Correct Answer Chromosome Immunoprecipitation

In class we discussed the adherence of a white blood cell (WBC) to endothelial cells upon a blood vessel wall. The changes in integrins that happened on the WBC are an example of Integrin inside-out signaling Integrin outside-in signaling Initiation of hemidesmosome formation Binding of selectins to integrins Detachment of a cell from basement MB - Correct Answer Integrin inside-out signaling Which of the following best describes a focal adhesion? A cluster of integrins linked to actin filaments A cluster of integrins linked to keratin filaments A cluster of cadherins linked to actin filaments A cluster of proteins forming a channel that is continuous with the neighboring cell A cluster of cadherins bound to collagen filaments - Correct Answer A cluster of integrins linked to actin filaments Which feature is found in the core promoter region of a gene and functions in the recruitment of RNA polymerase to the start site of transcription? TATA Box enhancer insulator distal element co-repressor - Correct Answer TATA Box Long non-coding RNAs (lncRNAs) function to regulate gene expression by Recruiting histone modifying enzymes Inducing degradation of mRNAs Directly acetylating histone tails

Tagging proteins to the proteasome Binding to the 5'UTR of mRNAs - Correct Answer Recruiting histone modifying enzymes Which enzymes are important for tissue remodeling and allowing cells to migrate through a tissue's extracellular matrix? Metalloproteinases Galactosidases Acetyltransferases Methyltransferases Glycosylesterases - Correct Answer Metalloproteinases Rigidity and shape of cells in an epithelial sheet is facilitated by Cellular junctions formed between cells and ECM that connect with the cellular cytoskeleton Degradation of the glycocalyx on the surface of the cell, facilitating ECM interactions Increased synthesis of peptidoglycans and their display on the cell surface Decreased secretory pathway activation in the cell, reducing the Golgi stacks in the cell Transition from protein synthesis on free ribosomes to mainly ER associated ribosomes - Correct Answer Cellular junctions formed between cells and ECM that connect with the cellular cytoskeleton Which type of junction mediates attachment of epithelial and endothelial cells to basement membranes? Hemidesmosome Adherins junction Gap junction Tight junction Desmosome - Correct Answer Hemidesmosome What kind of experiment could you do to identify specific DNA sequences/regions where transcription factors bind in a specific gene's promoter? DNA Footprinting

Microarray RNA Sequencing In situ Hybridization Western Blot - Correct Answer DNA Footprinting You are studying an integral, single pass transmembrane protein. You examine the structure and find that the amino acids on the N-terminal side of the transmembrane segment are positively charged. You can therefore make the following prediction: The N terminus of the protein is cytosolic The C terminus of the protein is cytosolic The N terminus of the protein is extracellular The protein may be cleaved after the transmembrane segment The protein is glycosylated at the N terminus - Correct Answer The N terminus of the protein is cytosolic Cadherins on the surface of one cell interact with this type of molecule on the surface of another cell Cadherins Integrins Selectins Fibronectin Peptidoglycan - Correct Answer Cadherins Basement membranes consist of a lattice of Collagen IV that is interconnected with a network of which of the following? Laminins Transcription Factors Translocons Adherins junctions Cytoskeleton - Correct Answer Laminins

Your grandmother takes daily glucosamine and chondroitin supplements. The reason these supplements may be beneficial is that the supplements Provide molecular building blocks for peptidoglycans Provide molecular building blocks for collagen Induce new cell turnover in the skin Induce molecular building blocks for laminin Induce adherins junctions in cells which can make bones stronger - Correct Answer Provide molecular building blocks for peptidoglycans Lysosomes are difficult to identify under the electron microscope, and many researchers use reagents that fluoresce in acidic environments. Why does this allow visualization of lysosomes in cells? Lysosomal compartments have low pH Lysosomal compartments have very high pH Lysosomal compartments are from vesicles that bud from the ER Lysosomal compartments are independent of the endomembrane system Lysosomal compartments originate from the nucleus of the cell - Correct Answer Lysosomal compartments have low pH In class we discussed the adherence of a white blood cell (WBC) to endothelial cells upon a blood vessel wall. The initial adherence, via selectins, was important because binding of selectins to the ligand on the WBC surface: caused the integrins on the WBC surface to adopt the upright conformation allowed cadherins to interact, forming adherins junctions increased interactions of the WBC with collagen of the connective tissue caused the integrins on the WBC surface to adopt the bent conformation prevented the WBC from aggregating with other WBCs in the blood stream - Correct Answer caused the integrins on the WBC surface to adopt the upright conformation

You attempt deletion mapping of a part of the promoter region of a particular gene. In your first experiment, you remove a short, 20 base pair sequence of nucleotides about 500 basepairs upstream of the transcription start site. Once the altered DNA is transfected into cells, the cells transcribe the gene in a normal fashion. What do you conclude? The sequence that was removed is not an essential part of the promoter. The sequence that was removed is an essential part of the promoter. The sequence that was deleted is an important determinant of the ability to transcribe the gene. The deleted sequence has a moderate level of importance in promoting transcription. The deleted sequence binds tightly to RNA polymerase. - Correct Answer The sequence that was removed is not an essential part of the promoter. Which molecules compose the glycocalyx? Glycolipids and glycoproteins in the plasma membrane Proteoglycans and laminins in the plasma membrane Proteoglycans and laminins in the basement membrane Glycolipids and glycoproteins in the basement membrane Collagens and laminins in the hemidesmosomes - Correct Answer Glycolipids and glycoproteins in the plasma membrane You are examining glycoproteins as they leave the trans Golgi network. Many of these glycoproteins contain fucose and sialic acids in addition to mannose and N- acetylglucosamine. The type of covalent linkages used in the addition of the fucose and sialic acids are: O-linkages N-linkages Di-sulphide bonds H-bonds SNAREs - Correct Answer O-linkages You are a student researcher interested in a gene called Dio3. This gene is expressed in cells in culture in the presence of thyroid hormone, but not expressed in the absence of

thyroid hormone. You are now examining Dio3 in the presence of a different molecule, retinoic acid. You have determined that in the presence of retinoic acid, Histone 3 Lysine 9 (H3K9) is highly methylated. In the absence of retinoic acid, H3K9 is acetylated. What can you conclude? Dio3 expression is likely repressed in the presence of retinoic acid Dio3 expression is likely increased in the presence of retinoic acid Retinoic acid probably does not regulate Dio3 expression Retinoic acid and thyroid hormone both induce expression of Dio Retinoic acid binds to the promoter region of the Dio3 gene - Correct Answer Dio expression is likely repressed in the presence of retinoic acid Which ONE of the following regions of an mRNA molecule can function in regulating initiation of translation, degradation, AND localization of the mRNA? 3'UTR 7 - methlyguanosine (5' cap) 5'UTR Exons PolyA tail - Correct Answer 3'UTR You are examining some electron micrographs from a cell and can make out some small, membrane enclosed vesicles. However, you cannot be sure of the origin and identity of these vesicles from the image alone. Which of the following could help you determine if these vesicles result from endocytosis? Presence of Clathrin coat Presence of COPII coat Presence of COPI coat Presence of signal sequence Fusion with ER membrane - Correct Answer Presence of Clathrin coat In your research lab, you have been asked to assist a graduate student who is studying the vesicular transport system. The graduate student asks you to stain a preparation of cells to

label vesicles transporting cargo between ER to Golgi. Which of the following markers would you stain for? COPII Clathrin Integrins Translocons COPI - Correct Answer COPII Which of the following enzymes typically acts to repress or prevent transcription? Histone Deacetylase Histone Acetyltransferase RNA Polymerase SWI/SNF Complex B-galactosidase - Correct Answer Histone Deacetylase Whereas all the carbohydrates in the plasma membrane faces outward on the external surface of the cell, all the carbohydrate on internal membranes faces toward the cytosol. T/F - Correct Answer F Which of the following is a characteristic of cyclic photosynthesis? Cyclic photosynthesis can absorb a broader spectrum of photon wavelengths. Cyclic photosynthesis only involves photosystem II. In cyclic photosynthesis the final electron acceptor is NADPH The final electron acceptor is photosystem II Cyclic photosynthesis only involves photosystem I. - Correct Answer Cyclic photosynthesis only involves photosystem I. Unsaturated fats are more likely to be liquid at room temperature. T/F - Correct Answer T Cells exist under conditions that are described as a steady state. Which of the situations below is not a feature of this cellular condition?

It requires cells to take up large amounts of energy from the environment. Energy use maintains molecular gradients of ions Reactions in the cell are at equilibrium. Products from one reaction are often used as reactants for another. - Correct Answer Reactions in the cell are at equilibrium. Nucleotides differ from nucleosides by what? The addition of three 3' phosphate groups The addition of a 3' phosphate group The addition of three 5' phosphate groups The addition of a 5' phosphate group - Correct Answer The addition of a 5' phosphate group Which is a form of active transport? Transport of water molecules through aquaporins. Transport of K+ ions by voltage-gated K+ channels. Transport of Na+ ions by ligand-gated Na+ channels. Transport of glucose by Na+ /glucose cotransporter. - Correct Answer transport of glucose by Na+ /glucose cotransporter. Which of the following act as electron acceptors in the oxidation of glucose? (chose all the apply) FAD H NAD+ ATP CO O2 - Correct Answer FAD NAD+ O

The reaction: ATP to ADP + Pi releases 7.3 kcal/mol of energy. Which one of these reactions would require just 1 ATP to proceed. 1,3 biphosphoglycerate to glyceraldhyde 3 - P, - 12.5kcal/mol Glucose to G- 6 - P, +3.3 kcal/mol Creatine to creatine-P, +11kcal/mol Active transport of Na ion, +9.4 kcal/mol PEP to pyruvate, - 14.8kcal/mol - Correct Answer Glucose to G- 6 - P, +3.3 kcal/mol The final electron acceptor in respiration is which of the following? FADH NAD+ O CO H20 - Correct Answer O Aside from the function of the mitochondrial ATP synthase to make ATP, this enzyme also transports ADP and ATP across the inner mitochondrial membrane transports electrons transports water across the inner mitochondrial membrane transports protons across the inner mitochondrial membrane - Correct Answer transports protons across the inner mitochondrial membrane Which of these are true statements about eukaryotic cell lipid bilayer. Permeable to many small compounds due to the presence of general porin proteins The two leaflets usually contain the same lipid composition. Due to the fluid nature of the lipid bilayer membrane associated proteins by default are evenly distributed throughout the membrane. The bilayer is permeable to charged protein ligands like cytokines. All of the above - Correct Answer Due to the fluid nature of the lipid bilayer membrane associated proteins by default are evenly distributed throughout the membrane.

In which organelle would one expect to find DNA? Golgi Microtubules Chloroplast Flagella - Correct Answer Chloroplast Concentration of sodium ions outside of a cell is mediated by the Na/K ATPase pump. This is an example of which of the following? Primary Active Transport Secondary Active Transport (symport/cotransport) Simple Diffusion Secondary Active Transport (antiport/exchange) - Correct Answer Primary Active Transport Which of the following is not a part of normal information flow in cells? Translation Replication Transcription Reverse Transcription - Correct Answer Reverse Transcription Which of the following is a purine? Uracil Adenine Cytosine Thymine - Correct Answer Adenine Under anaerobic conditions or in the absence of functional mitochondria, glycolysis in mammalian cells generates what product(s) that contain the carbons from glucose? pyruvate and lactate ethanol and carbon dioxide carbon dioxide lactate

pyruvate - Correct Answer lactate Molecules such as large proteins enter and exit the nucleus through which of the following? Through diffusion through the membrane Through passive transport Through a GTP dependent passive pore Through secondary active transport - Correct Answer Through a GTP dependent passive pore In photosynthesis, what is NADPH required for? Cyclic photosynthesis Carbon reduction Splitting water The electron transport chain - Correct Answer Carbon reduction Loss of telomerase activity is especially problematic for neurons because they are not able to divide to replace themselves (T/F) - Correct Answer F You clone the GFP (green fluorescent protein) with a promoter into chromosome 7 of a cultured human cell. You verify that it is indeed encode on the chromosome but the cell does not fluoresce. After sequencing you notice the gene has inserted very close to end of the chromosome. Why is the cell not fluorescent. The DNA was converted to heterochromatin because it was close to the telomeres The DNA was converted to euchromatin because it was close to the centromere. The sequence was lost due to chromosome shortening during replication The DNA was converted to euchromatin because it was close to the telomeres The activity of telomerase mutated the sequence

The DNA was converted to heterochromatin because it was close to the centromere. - Correct Answer The DNA was converted to heterochromatin because it was close to the telomeres Glycolysis is dependent on which of the following (choose the best answer) N O CO ATP - Correct Answer ATP The first electron acceptor in the oxidation of glucose is? NADH O H NAD+ CO2 - Correct Answer NAD+ There are five major types of histones in eukaryotic cells. One of these is not part of the structure of nucleosomes and is thought to participate in forming the 30 - nm condensed chromatin fiber. Which histone is this? H2A H H H2B H4 - Correct Answer H Which of the following is least likely to cross a lipid bilayer? CO H2O Ethanol Na+ - Correct Answer Na+ Blood glucose concentration is higher than the glucose concentration in muscle cells. The transport of glucose from blood into muscles is likely mediated by _______. sodium-coupled cotransporters. potassium-coupled cotransporters.

facilitated diffusion. simple diffusion (no transporters are needed). - Correct Answer facilitated diffusion. In the first step of the TCA cycle Acetyl CoA is added to a _____ carbon compound to make a ______carbon compound. 2 and 5 1 and 3 3 and 4 4 and 6 - Correct Answer 4 and 6 The nuclear pore complex allows for: (select all that apply) Import of proteins The maintenance of the isotonic conditions of the nuclear matrix Passive diffusion of smaller molecules Creation of an ion gradient - Correct Answer Import of proteins Passive diffusion of smaller molecules Which electron carrier in the ETC of mitochondria accepts electrons from NADH and ultimately transfers them to coenzyme Q. Complex II Complex I Complex III NADH dehydrogenase - Correct Answer Complex I Potassium cyanide is a poison which combines with cytochromes to prevent binding of oxygen to the enzyme without altering the Km of the reaction. Which type of inhibition does this represent. Noncompetitive inhibition

Enzymatic inhibition Reversible inhibition Competitive inhibition - Correct Answer Noncompetitive inhibition Movement of lipid soluble molecules such as steroids through the plasma membrane is an example of which of the following? Facilitated Diffusion Secondary Active Transport (antiport/exchange) Simple Diffusion Secondary Active Transport (symport/cotransport) Primary Active Transport - Correct Answer Simple Diffusion A typical eukaryotic cell has a ratio of ATP:ADP in the cytosol of about 200:1 while in water the ratio would be 1:1000000. In water ATP:ADP would be at ___________, while in the cell ATP:ADP would be at ____________. High energy state, Low energy state Equilibrium, Steady state Endergonic, Exergonic Steady state, Equilibrium - Correct Answer Equilibrium, Steady state What is the primary energy source that drives the Na+ /K+ pump? K+ ion gradient. Na+ ion gradient H+ gradient. ATP hydrolysis - Correct Answer ATP hydrolysis What is the source of the electrons that reduce photosystem II? Photons H2O

ATP

The electron transport chain Chlorophyll molecules in the antenna complex - Correct Answer H2O If photosynthesizing leaves are provided with CO₂ labeled with heavy oxygen (18O), later analysis will show that all but one of the following compounds produced by the leaves contain the 18O label. That one is: glucose 3 - phosphoglycerate O₂ glyceraldehyde 3 - phosphate (G3P) ribulose bisphosphate (RuBP) - Correct Answer O₂ Almost all of the oxygen (O2) one consumes in breathing is converted to: Carbon dioxide Water Carbon monoxide and then to carbon dioxide by electron transport Acetyl-CoA - Correct Answer Water The release of the first fully oxidized carbon atom from the metabolism of glucose occurs during which step. Pyruvate dehydrogenase The TCA cycle Passage of electrons to the electron transport chain Glycolysis - Correct Answer Pyruvate dehydrogenase Which of the following classes of macromolecules is not a polymer? Nucleic Acids All the above are polymers Proteins Polysaccharides

Lipids - Correct Answer Lipids Cells can simultaneously concentrate glucose in the cytoplasm using the energy of a chemical gradient as well as utilizing passive glucose transporters that allow glucose to diffuse out of the cell. How is this accomplished? The transporters are spatially restricted; transporting glucose to specific compartments. The transporters work fast enough that they don't compete with each other. The transporters work together; one couples a favorable chemical gradient to both transporters. The transporters are temporarily regulated only one functions at a time. - Correct Answer The transporters are spatially restricted; transporting glucose to specific compartments. What step makes a C3 plant different from a C4 plant? H2O is not used in the light reactions. The electron transport chains differ in length The capturing of light energy using both photosystem I and II The fixation of CO2 immediately to a 5 - carbon molecule The use of the enzyme RuBisCo - Correct Answer The fixation of CO2 immediately to a 5 - carbon molecule nder aerobic conditions what is the fate of the high energy electrons generated from glycolysis? (chose all the apply) Stored as malic acid for later use Used to generate ATP in the mitochondria using the electron transport chain Passed to pyruvate to generate lactic acid Stored for a length of time as NADPH to be used when oxygen is available Passed to FAD+ in the mitochondria - Correct Answer Used to generate ATP in the mitochondria using the electron transport chain Passed to FAD+ in the mitochondria

The base composition of a virus was found to be 18% A, 32% G, 18% T and 32% C. The virus is single-stranded DNA virus The virus is double-stranded RNA virus The virus is double-stranded DNA virus The virus is single-stranded RNA virus - Correct Answer The virus is double-stranded DNA virus Assuming that you do not pass through a pore, how many lipid bilayers separate the exterior of the eukaryotic cell from the DNA during G1 phase? 4 2 5 3 1 - Correct Answer 3 Which of the following would be visible with an electron microscope but not a light microscope? Epithelial cell Bacteria Cellular organelles Virus - Correct Answer Virus In which part of the cell does the assembly of the ribosomal subunits occur. In the nucleolus Attached to the nuclear lamina In the lumen of the nuclear envelope On the rough ER During transit through the nuclear pore complex - Correct Answer In the nucleolus

Otto Warburg was one of the pioneering scientists who elucidated the biochemical basis of glycolysis in the early 1900s. He also made a puzzling discovery about cancer cells that remains interesting and relevant today. Normal differentiated cells, which do not proliferate, rely primarily upon aerobic respiration to generate ATP, except when they experience decreased levels of oxygen, in which case they switch to glycolysis. In contrast, cancer cells rely almost entirely upon glycolysis for producing ATP, regardless of the presence of oxygen. Cancer cells can increase the rate of glycolysis up to 200 - fold relative to normal differentiated cells. This phenomenon, known as the Warburg effect, is still poorly understood. It is also a focus of renewed interest because it suggests a unique attribute of cancer cells that could be exploited to kill them selectively. Which of the following properties of cancer cells would hav - Correct Answer Increased release of lactate What is the basic mechanism by which ATP synthase generates ATP in the mitochondria? Uses electrochemical energy to directly create a high energy chemical bond Inside the mitochondria the formation of ATP is energetically favorable and does not require input energy. Uses the GTP from the TCA cycle to drive ATP synthesis Converts mechanical energy to chemical energy - Correct Answer Converts mechanical energy to chemical energy The majority of the carbon dioxide produced during respiration is the product of which process Photosythesis Glycolysis TCA cycle Calvin cycle - Correct Answer TCA cycle The inactivated X-Chromosome in female mammals is an example of which? Heterochromatin Constituve euchromain Allelelic exclusion Facultative euchromatin