Help
Options
Question
What is the function of karyopherins?
click to flip
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't know
Question
Ribosomes contain one copy each of 5.8S, 18S, and 28S rRNA. The major mechanism ensuring that each is produced in equal molar amounts is
Remaining cards (214)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Cell bio practice 2
| Question | Answer |
|---|---|
| What is the function of karyopherins? | They transport macromolecules into or out of the nucleus. |
| Ribosomes contain one copy each of 5.8S, 18S, and 28S rRNA. The major mechanism ensuring that each is produced in equal molar amounts is | the grouping of the DNA sequences encoding each rRNA into a single rRNA gene. |
| Altered gene expression is one possible explanation for the phenotypic consequences of nuclear lamina diseases. The other is | mechanical stress |
| Most snoRNAs function as | guide RNAs. |
| The directionality of nuclear protein import is determined by | an unequal distribution of Ran/GTP |
| Which of the following are not subcompartments of the nucleus? | Lipid droplets |
| An important step in the import of the transcription factor NF-κB into the nucleus is regulated by a | protease |
| The nuclear basket protein complex is a component of the nuclear pore complex found | inside the nucleus |
| Chromosomes are distributed in the nucleus | in distinct territories |
| Which of the following does not take place in the nucleus? | Translation |
| “Classical” nuclear localization signals are composed primarily of | basic amino acids |
| The location of Ran GAP in association with the cytoplasmic filaments of the nuclear pore results in the conversion of the nucleotide bound to Ran in the nucleus to | GDP |
| Which of the following statements about heterochromatin is false? | It is transcriptionally active |
| Initial steps in the functional assembly of snRNPs occur in the | cytoplasm |
| mRNA molecules are exported from the nucleus to the cytoplasm via | a recruited protein complex |
| The outer nuclear membrane is contiguous with the | endoplasmic reticulum |
| The fibrous proteins underlying the inner nuclear membrane are | lamins |
| What is the average number of replication forks per DNA replication cluster in a mammalian cell nucleus? | Approximately 20 |
| snRNPs that are responsible for pre-mRNA splicing are assembled and stored in | both Cajal bodies and speckles. |
| Which of the following is a possible intermediate during pre-rRNA processing? | An RNA molecule containing 5.8S + 28S rRNAs |
| The nucleolus is the site where | ribosomal RNA is transcribed and ribosomes are partially assembled. |
| The most prominent nuclear body is the | nucleolus |
| Protein transport into the nucleus occurs by | selective transport through the nuclear pores |
| Which of the following factors contributes to the comparative ease of determining how pre-rRNA is processed? | - The abundance of rRNA genes - The abundance of ribosomes (5–10 million) that need to be synthesized per cell cycle - The grouping of rRNA genes into discrete nuclear subcompartments, the nucleoli |
| The nuclear pore complex of proteins is estimated to have a mass | about 30 times that of a ribosome |
| Cargo proteins are transported through the Golgi apparatus | by a process(es) that remain controversial and may include elements of both vesicular transport and cisternal maturation. |
| The trans-Golgi network is a hub for protein sorting to many destinations. Mitoch and chlorop are examples of organelles that are not part of the sec pathway. What is the most plausible explanation for their absence from the secretory pathway? | Their evolutionary origin through endosymbiosis |
| The lumen of the ER is equivalent topologically to the | extracellular space |
| Which of the following would you expect to find at high concentrations in lysosomes? | Degradative enzymes |
| As they emerge from the ribosome, signal sequences are recognized and bound by a(n) | signal recognition particle (SRP) |
| For many yeast proteins, posttranslational translocation of proteins targeting the ER is | a process affecting many newly synthesized proteins. |
| The major site at which membrane lipids are synthesized is the | cytosolic side of the ER membrane |
| Which of the following is not a destination for vesicles leaving the Golgi apparatus? | Mitochondria |
| Proteins that span the membrane multiple times have multiple _______ that alternate with multiple transmembrane stop-transfer sequences | internal signal sequences |
| Clathrin-coated vesicles are involved in | the uptake of extracellular molecules by endocytosis and the transport of molecules from the trans-Golgi network to the lysosomes. |
| Which of the following lipids is/are synthesized in the Golgi apparatus? | Glycolipids |
| In some proteins the only transmembrane sequence is located C-terminally in the protein. These proteins are recognized by | TRC40 (GET3) |
| Which of the following is not a contiguous membrane domain? | Secretory granules |
| The trans-Golgi network is | the exit part of the Golgi where sorting of proteins to the lysosomes, plasma membrane, and cell exterior occurs. |
| N-linked glycosylation at an Asn-X-Ser/Thr consensus sequence adds _______ sugar(s) in a single step to the protein. | 14 |
| Which of the following statements about transmembrane proteins is true? | They usually have one or more α helices spanning the membrane bilayer. |
| Proteins are translocated into the ER lumen | through an aqueous channel created by the Sec61 protein. |
| The ribosomes of the rough endoplasmic reticulum are targeted to the cytoplasmic side of the membrane via | a sequence within the protein being synthesized |
| Which of the following is not involved in the specific targeting of proteins to lysosomes? | N-linked glycosylation in the ER |
| Calreticulin assists in folding glycoproteins that contain one _______ residue | glucose |
| In cell fractionation experiments in which subcellular organelles are separated on the basis of their density, the smooth endoplasmic reticulum is _______ the rough endoplasmic reticulum. | lighter than |
| In the “pulse-chase” experiment, Palade studied the pathway taken by secreted proteins in pancreatic acinar cells by labeling them.Which of the following represents the correct order in which the proteins were identified? | Rough ER → Golgi apparatus → secretory vesicles |
| The sequence Lys-Asp-Glu-Leu (KDEL) serves to retain proteins in the ER by | binding to receptors within the membranes of the ERGIC and Golgi, which retain them or return them to the ER. |
| The process by which cells degrade their own components by enclosing them in a cytosolic membrane is | autophagy |
| The major model of vesicle fusion holds that actual fusion of a vesicle with its target membrane is driven by the interaction of pairs of proteins called vesicle and target | SNAREs |
| Which of the following is not involved in protein transport into mitochondria? | Vesicular transport |
| Where do phospholipids in mitochondrial membranes such as phosphatidylcholine and phosphatidylethanolamine originate? | In the ER |
| What is the major site of energy production in the form of ATP in human cells? | The inner mitochondrial membrane |
| Which of the following plastids is a precursor to all other plastids? | Proplastid |
| The amino terminal presequence on proteins imported into the mitochondrial inner membrane is | cleaved by mitochondrial matrix processing peptidase (MPP). |
| What triggers lipid-containing etioplasts to undergo complete development into chloroplasts? | Light |
| _______ different translocon systems are used for protein import from the chloroplast stroma into the thylakoid lumen or membrane. | Three |
| In terms of its role in the generation of metabolic energy, the inner membrane in mitochondria is equivalent to which of the following in chloroplasts? | The thylakoid membrane |
| Zellweger syndrome is caused by a defect in | protein import into peroxisomes. |
| The carotenoids, which give many plants their yellow, orange, and red colors, are located in | chromoplasts. |
| Peroxisomes are involved in all of the following reactions except | the biosynthesis of the enzyme catalase, which breaks down hydrogen peroxide. |
| Assuming that human mitochondria contain about 1,500 different proteins, approximately what percentage of the mitochondrial proteome is encoded by mitochondrial DNA? | 1.00% |
| Mitochondria differ from other organelles such as lysosomes and the Golgi apparatus in that they | contain their own genomes. |
| A deficiency in cardiolipin would lead to | increased proton flow across the inner mitochondrial membrane. |
| The human mitochondrial genome encodes only 22 tRNAs. This limited array of tRNAs can read the 64 possible triplet codons through extreme wobble in base pairing at the third codon position and the use of a(n) _______ genetic code. | nonuniversal mitochondrial |
| Chloroplast genomes contain approximately how many genes? | 150 |
| If a drug blocked the activity of the mitochondrial inner membrane proteins Tim9 and Tim10, which of the following would most likely not be found in the outer mitochondrial membrane? | β-barrel proteins |
| Human diseases caused by mutations in mitochondrial genomes | are inherited from the mother. |
| Which of the following is not a protein translocon/translocase found in the mitochondrial inner or outer membrane? | Toc75 |
| Which statement correctly describes the difference between the proton gradient across the inner mitochondrial membrane and the proton gradient across the thylakoid membrane of chloroplasts? | The first creates an electrochemical gradient, while the second is largely a chemical gradient. |
| The major cation responsible for regulating actin-myosin contraction is | Ca2+ |
| The approximate diameter of an actin filament is | 7 nm. |
| Which of the following is not a function of actin-binding proteins? | Incorporation of microfilaments into the extracellular matrix |
| Which of the following microtubules are attached to chromosomes? | Kinetochore microtubules |
| In cell movement, branched actin filament growth pushes against the cell membrane. Proteins involved in this process include all of the following except | vinculin |
| Which of the following cytosolic proteins in red blood cells is the link between the plasma membrane and the spectrin/actin network beneath the cell surface? | Ankyrin |
| Which of the following is not true of the assembly of actin filaments? | It requires ATP |
| Which of the following is not one of the functions of the cytoskeleton? | Protein translocation into the ER |
| Which of the following statements about intermediate filaments is true? | Rather than consisting of a single type of protein, they can be made up of a number of different proteins |
| Actin may be cross-linked into either parallel or _______ bundles. | contractile |
| Which of the following statements about cilia is false? | They are projections of the plasma membrane supported by microfilaments. |
| The basis for muscle contraction is the | sliding of myosin and actin fibers past each other. |
| The discovery that the intermediate filament protein keratin is essential for mechanical strength of epithelial cell layers was made in | transgenic mice. |
| Which of the following does not mediate the association between actin filaments and the plasma membrane? | Direct interaction between actin and plasma membrane proteins |
| Like myosins, kinesins and dyneins are both families of proteins. Which of the following statements is true of all kinesins and dyneins? | They are microtubule-dependent motors |
| Kinesin and dynein are | microtubule motor proteins. |
| Whether a microtubule shrinks or grows is determined by | the rate of GTP-bound tubulin addition relative to the rate of tubulin GTP hydrolysis. |
| Which of the following statements about myosin I is true? | It links the actin bundles to the plasma membrane in the microvilli of intestinal cells. |
| Myosin II is found in skeletal muscle and the contractile ring. Other myosins do not form thick filaments and are still capable of producing movement To what do the tail(s) of myosin I and myosin V bind? | Cargo such as membrane vesicles or intermediate filaments |
| Cofilin plays a role in the | disassembly of actin filaments |
| A centrosome is | the major microtubule-organizing center in animal cells. |
| Although Na+ is smaller than K+, its passage through the K+ channel is blocked by the _______ filter. | selectivity |
| Which of the following statements about ABC transporters is false? | Each member of the family is a Cl– channel. |
| Membrane proteins are able to move | laterally within the plane of a membrane. |
| Transport of glucose into the intestinal epithelium is driven by ion gradients established by the | Na+-K+ pump |
| The resting plasma membrane potential as described by the Nernst equation is the sum of the movement of many ions. However, in practice, the movement of _______, a single ion, is the major component determining membrane potential. | K+ |
| Which of the following statements about the relative concentrations of Na+ and K+ inside and outside of a typical mammalian cell is true? | The concentration of Na+ outside the cell is about 30 times higher than inside the cell, and the concentration of K+ inside the cell is 10 to 30 times higher than outside the cell. |
| Which of the following will not solubilize a typical peripheral membrane protein? | Mildly hypertonic saline |
| Mutations in the internalization signal of endocytic receptors prevent their interaction with | adaptor proteins |
| LDL uptake by cells is one of the functions of | receptor-mediated endocytosis. |
| Which of the following are integral membrane proteins that do not contain a transmembrane α helix? | Glycosylphosphatidylinositol (GPI)-anchored proteins |
| The ingestion of large particles by cells is a form of endocytosis known as | phagocytosis. |
| Which of the following is not involved in receptor-mediated endocytosis? | Pseudopodia |
| Two examples of membrane lipids that are present in small amounts are | glycolipids and phosphatidylinositol |
| Which of the following lipids are distinctly enriched in lipid rafts? | Cholesterol and sphingolipids |
| What is the primary reason that mammalian red blood cells are used in the study of the plasma membrane? | They lack nuclei and membrane-bounded organelles |
| The pH of endosomes and lysosomes is | acidic |
| A feature common to most transmembrane proteins is | an α-helical region of about 20 to 25 hydrophobic amino acids |
| Active transport differs from facilitated diffusion in that | active transport involves the transport of molecules up their concentration gradient |
| Which of the following statements about ion channels is true? | They are opened either by the binding of ligands or by changes in electric potential across the membrane |
| Which of the following statements about the glucose transporter is false? | Flow through it is unidirectional |
| The major function of adhesion proteins such as fibronectin is to | link collagen, proteoglycans, and cells containing integrins. |
| Homophilic interactions between cells involve interactions | among adhesion molecules of the same molecular class. |
| Adherens junctions and desmosomes may be distinguished from each other on the basis of | the linkage of cadherins either to actin filaments or to intermediate filaments, respectively. |
| Cellulose, chitin, and hyaluronan are all deposited extracellularly by | plasma membrane enzyme complexes |
| The cell–cell interactions mediated by the selectins, integrins, and most members of the Ig superfamily are _______ interactions in which the cytoskeletons of adjacent cells are not linked to one another. | transient |
| A major function of tight junctions is to | seal the space between adjacent cells to provide, for example, a barrier to sugar diffusion across an epithelial cell layer. |
| Fibrous structural proteins of the extracellular matrix are embedded in gels formed from polysaccharides called | glycosaminoglycans (GAGs). |
| Which of the following statements about collagen is false? | It forms a double helix, with two collagen molecules wrapped around each other in a ropelike structure. |
| What is the difference between Gram-positive and Gram-negative bacteria? | Gram-positive bacteria are surrounded by a single membrane, whereas Gram-negative bacteria are surrounded by a double membrane, with an outer membrane that is porous to ions and small molecules. |
| During the biosynthesis and transport of collagen from the endoplasmic reticulum through the Golgi apparatus to the cell surface, collagen fibrils form extracellularly. Which of the following does not help to explain why this happens? | Type I procollagen cannot form the triple helical oligomers that are the core structure of any collagen oligomer. |
| _______, although structurally different from gap junctions in animal cell tissues, may be thought of as the functional equivalent of gap junctions in plants. | Plasmodesmata |
| The junctions between animal cells that allow the free passage of molecules smaller than approximately 1,000 daltons are called | gap junctions |
| The basic structural polysaccharide of fungal cell walls, crab shells, and insect exoskeletons is | chitin |
| Animal cells are embedded in a(n) | extracellular matrix. |
| Specific recognition between cell types such as leukocytes and endothelial cells of blood vessels is mediated by cell-surface glycoproteins called | selectins |
| Which of the following is not one of the major transmembrane proteins in tight junctions? | Thrombospondin |
| Primary plant cell walls are cross-linked by | pectin |
| A mutation in the bacterial gene encoding crescentin would likely have an effect on which type of bacteria? | Curved or spiral-shaped |
| Proteins of the _______ family link transmembrane proteins of the tight junction to actin. | zonula occludens |
| Integrins link extracellular matrix proteins either directly or indirectly to all of the following intracellular proteins except | laminin |
| Which of the following statements about integrins is false? | Signals from the extracellular matrix activate integrins to assume a head-group-extended conformation. |
| Which of the following is not a therapeutic effect of aspirin? | Stimulation of the growth of fibroblasts at the site of a wound, thus aiding the healing process |
| Which of the following signaling pathways allow for direct cell–cell signaling by transmembrane proteins? | Notch |
| Which of the following is not a commonly observed consequence of the binding of a signaling molecule to its cell surface receptor? | Increased synthesis of the receptor |
| G protein-coupled receptors are important molecules involved in signal transduction. Which of the following statements about G protein-coupled receptors is true? | They generally contain seven membrane-spanning α helices. |
| Which of the following steroid hormone(s) is/are not secreted by the gonads? | Corticosteroids |
| An example of signaling by direct cell–cell interactions is | the Notch pathway |
| Most of the effects of cyclic AMP (cAMP) in the cell are mediated by | protein kinase A |
| Which of the following statements about protein kinase A (PKA) is false? | PKA binds a total of four molecules of cAMP, one on each of the four subunits. |
| Receptor protein-tyrosine kinases represent critical molecules involved in growth and differentiation. Which of the following is not a common structural feature of all receptor protein-tyrosine kinases? | A single polypeptide |
| In unstimulated cells, NF-κB proteins are maintained in an inactive state in the cytosol by interactions with | IκΒ |
| Heterotrimeric G proteins are not the only guanine nucleotide-binding proteins. Which of the following also represents a family of GTP-binding proteins that act as monomers instead of being a heterotrimeric compound? | Ras |
| Which of the following is an example of endocrine signaling? | Insulin release by β cells in the pancreas, mediating an effect of glucose uptake by muscle cells |
| The MEK kinase (MAP kinase/ERK kinase) is unusual in that it | is a dual-specificity kinase, having the ability to phosphorylate both threonines and tyrosines |
| The signaling molecule nitric oxide (NO) functions | by diffusing across the cell membrane and changing the activities of intracellular enzymes |
| SH2 domains are | protein domains that bind phosphotyrosine-containing peptides. |
| Which of the following hormone(s) is/are not synthesized from cholesterol? | Retinoic acid |
| Which of the following statements regarding heterotrimeric G proteins in a resting state is true? | The proteins are in a complex with G protein-coupled receptors. |
| Integrins are transmembrane proteins that connect | the extracellular matrix to the cytoskeleton |
| Cyclic AMP (cAMP) is synthesized from ATP by the action of | adenylyl cyclase |
| The term “paracrine signaling” refers to | signaling between cells located close to each other |
| Which of the following statements about G protein signaling is false? | The α subunit becomes deactivated when the hormone dissociates from the receptor |
| What is the difference between neurotransmitters and neuropeptides? | Neurotransmitters are small hydrophilic molecules and neuropeptides are small proteins. |
| In the absence of growth factor, most animal cells will stop the cell cycle at a restriction point in what stage? | G1 phase |
| Which of the following statements about cyclin B is false? | It cycles between active and inactive states in the cell cycle. |
| The G2 cell cycle checkpoint detects | unreplicated or damaged DNA |
| Which of the following are not phosphorylated by the Cdk1/cyclin B complex during mitosis? | Histone H3 |
| Which of the following is not involved in metaphase II arrest during meiosis? | An increase in cytoplasmic calcium levels |
| At fertilization, the sperm binds to a receptor on the surface of the egg and fuses with the plasma membrane, initiating the development of a new diploid organism. Which of the following statements about fertilization is false? | The progression of metaphase II to anaphase is triggered by the activation of MPF. |
| During what phase of meiosis does recombination between maternal and paternal chromosomes occur? | Prophase I |
| Most cells in an adult animal are | in G0, or quiescent, phase. |
| The phase of the cell cycle that corresponds to the interval between mitosis and initiation of DNA replication is referred to as the | G1 phase |
| Which of the following is not one of the phases of mitosis? | S phase |
| The sequence of DNA on each chromosome where the sister chromatids are held together is called the | centromere |
| The spindle assembly checkpoint monitors the alignment of chromosomes in the mitotic spindle during mitosis. If the chromosomes do not align properly, the spindle assembly checkpoint will arrest cells in what phase of mitosis? | Metaphase |
| DNA content can be determined using a method of flow cytometry that can determine 2n or 4n states of cells based on cell counting and fluorescent labeling of DNA. Which of the following phases would be identified through flow cytometry as 2n? | G1 phase |
| Cell cycle checkpoints ensure that complete genomes are transmitted to daughter cells. DNA damage checkpoints are found in all of the following phases except | M phase. |
| Which of the following statements regarding cyclin D is false? | It is always present and its activity is regulated by fluctuating levels of Cdk4 and Cdk6. |
| In which of the following cell types do G1 and G2 not take place? | Early embryonic cells |
| Interphase is defined as | the G1, G2, and S phases |
| The p21 and p15 proteins are examples of | Cdk inhibitors |
| You perform an experiment by incubating a radiolabeled nucleotide into the medium of a culture of cells. The cells that take up the radiolabel would be expected to be in what phase of the cell cycle? | S phase |
| The progression from metaphase to anaphase is triggered by | ubiquitin-mediated proteolysis of key proteins |
| In yeast, START triggers the progression from G1 to S. Which of the following are involved in regulating START? a. Nutrients b. Mating factors c. Cell size d. All of the above | All of the above |
| Which of the following products would result from caspase cleavage of a protein with the amino acid sequence AVEELCSTWYYDLLCHMRTL? | AVEELCSTWYYD + LLCHMRTL |
| Which of the following is/are not considered a viable of stem cells? | Tumors |
| The Bcl-2 family of proteins is divided into three functional groups that contain and share as many as four Bcl-2 homology domains (BH domains). Which of the following is common to all members of the Bcl-2 family? | BH3 |
| Which of the following statements about cloning by somatic cell nuclear transfer is false? | The cloned embryo is genetically identical to the foster mother. |
| Inhibitors of apoptosis (IAPs) regulate caspases. Which of the following statements about IAPs is false? | IAPs are activated through the p53 pathway. |
| What is the best rationale for the use of therapeutic cloning to replace defective cells or tissues in a patient? | The transplanted cells are identical to those of the recipient who donated the adult nucleus, so complications of immune rejection are avoided. |
| The PI 3-kinase pathway is important in countering apoptosis in healthy cells and promotes cell survival. Which of the following statements about the PI 3-kinase pathway is false? | Activated Akt phosphorylates and activates Bad |
| In reference to stem cells, which of the following statements is false? | Stem cells in organs can only differentiate into the tissue in which they are located. |
| Which of the following stem cells have the capacity to give rise to all the differentiated cell types of adult organisms? | Embryonic stem cells |
| Bone marrow transplants are used to treat patients with which of the following diseases? | Aplastic anemia, Hemoglobin disorders, Immune deficiencies |
| Which of the following diseases would not be an ideal target for therapeutic cloning? | HIV |
| Apoptosis, or programmed cell death, occurs in all of the following cases except | in cells damaged by injury. |
| Which of the following events is not associated with apoptosis? | Cell cycle reentry |
| Some differentiated cells retain the ability to proliferate as needed to repair damaged tissue throughout the life of the organism. Which of the following cell types do not retain this unique ability? | Neurons |
| Murine embryonic stem cells are grown in the presence of a growth factor. What growth factor is generally used for this? | LIF (leukemia inhibitory factor) |
| The following is a signal transduction cascade ending with activation of apoptosis by the BH3-only proteins PUMA and Noxa: Double-stranded DNA damage; Chk2; _______; PUMA/Noxa; apoptosis. Which protein belongs in the blank space? | p53 |
| TNF and related cytokines can directly induce apoptosis. Which of the following statements about TNF-mediated induction of apoptosis is true? | TNF binds a trimeric receptor complex on the surface of the membrane, Upon receptor binding, caspase-8 is activated through an adaptor protein, Caspase-8 activates Bid, which in turn activates Bax and Bak and then feeds into the mitochondrial pathway. |
| Which of the following statements about caspases is false? | They predominantly break up Golgi membranes, which in turn release other caspases to cleave nuclear lamins and cytoskeleton proteins. |
| Which of the following cells cannot develop from hematopoietic stem cells? | Satellite cells |
| Which of the following statements is true in reference to Bax and Bak, two members of the Bcl-2 family? | When activated, Bax and Bak form oligomers in the outer membrane of mitochondria, leading to the release of cytochrome c. |
| Which of the following is not one of the ways in which oncogenes incorporated into viral genomes can differ from their normal cellular counterparts (proto-oncogenes)? | They can be present in many tandem copies, as opposed to the single copy present in the cell. |
| The PDGF receptor is a proto-oncogene (a normal cellular gene that, when mutated, becomes oncogenic). Which of the following statements about the PDGF receptor is true? | The oncogenic mutation occurs in the extracellular amino terminal end of receptors., The oncogenic mutation constitutively activates the intracellular kinase activity , The oncogenic mutation generates a receptor that is no longer dependent on ligands |
| Which of the following tumor suppressor genes has been associated with colon cancer? | APC, p53, Smad2 or Smad4 |
| The most lethal type of cancer in the United States is cancer of the | lung |
| Pioneering work by Judah Folkman led to a class of anticancer drugs, such as sunitinib and sorafenib. These drugs function by | inhibiting the formation of new blood vessels in the vicinity of the tumor. |
| Which of the following statements concerning the difference between cancer cells and normal cells is false? | Cancer cells undergo normal differentiation, but excessive proliferation |
| Which of the following statements about the tumor suppressor gene p53 is false? | It is the cause of the rare childhood cancer of the eye, retinoblastoma |
| Oncogenic conversion of the two dimerizing proto-oncogene components of the AP-1 transcription factor can lead to abnormal cell proliferation. Which of the following two gene products form the active AP-1 transcription factor complex? | Fos and Jun |
| Which of the following statements about papillomaviruses is false? | They have been shown to cause both benign and malignant breast cancer. |
| Which of the following statements about cancers is false? | Lymphomas are malignancies from colon tissue. |
| Infection with which of the following viruses is associated with development of liver cancer in humans? | Hepatitis B viruses |
| PTEN is a tumor suppressor gene in the Akt signaling pathway. Which of the following statements about PTEN/Akt is false? | PIP2 can be oncogenically mutated to induce cell survival. |
| What is the difference between a benign tumor and a malignant tumor? | A malignant tumor has the ability to spread to other tissues and to initiate tumors at secondary sites, whereas a benign tumor does not spread. |
| Which of the following has not been found to cause cancer? | Bacteria |
| The more than 40 oncogenic retroviruses that have been identified share expression of all of the following genes except | src. |
| Which of the following genes is expressed by SV40 (simian virus 40) and induces transformation? | The gene encoding large T antigen |
| Angiogenesis contributes to cancer development by | providing nutrients and oxygen to tumors and by facilitating metastasis |
| Burkitt's lymphoma is caused almost exclusively by | translocation of the c-myc proto-oncogene. |
| The majority of oncogene proteins are | components of signaling pathways that regulate cell proliferation. |
| People infected with HIV are more susceptible to acquiring certain types of cancer because | these individuals are immunosuppressed |
Created by:
awahay