Description : How do viruses attach to host cells?
Last Answer : By binding to receptors
Description : What is true about viruses without exception? (1) They contain a core of RNA (2) They can infect bacteria (3) They cannot produce antibodies (4) They can multiply only in host cells
Last Answer : (4) They can multiply only in host cells Explanation: Viruses do not contain enzymes for energy production or protein synthesis. For a virus to multiply, it must invade a host cell and direct the host ... proteins, and copies of its nucleic acid, using the host cell's ATP to power the reactions.
Description : A viral load test detects the A- provirus of HIV in infected cells B- .total amount of virus in the infected host C- number of viruses being released by each infected cell D- .amount of bacteriophage being produced by E. coli cells
Last Answer : provirus of HIV in infected cells
Last Answer : They can multiply only in host cells
Description : Who demonstrated that viruses are inert outside the host cell and can be crystallised?
Last Answer : Who demonstrated that viruses are inert outside the host cell and can be crystallised?
Description : What is found in some viruses and are external lipid membranes borrowed from the host cell.?
Last Answer : Lipid membrane called the Envelope
Description : The non-living characteristic of viruses is – (1) ability to multiply only inside the host (2) ability to cause diseases in the host (3) ability to undergo mutation (4) ability to be crystallise
Last Answer : (4) ability to be crystallise Explanation: Viruses are known as a connecting link between non-living and living being.
Description : The oncogene theory states that transforming genes a. Normally Occur In The Host Genome. b. Can Exist In Viruses. c. Are Not Of Viral Origin. d. All Of The Above (A—C) Are Correct.
Last Answer : d. All Of The Above (A—C) Are Correct
Description : Usually viruses are separated into several large groups based primarily on A.nature of the host B.nucleic acid characteristics C.capsid symmetry D.diameter of the viroin or nucleocapsid
Last Answer : A.nature of the host
Description : Recombination of virus genomes occurs A- by transduction B- by transcription C- simultaneous infection of a host cell by two viruses with homologous chromosomes D- by transformation
Last Answer : simultaneous infection of a host cell by two viruses with homologous chromosomes
Description : What Processes depend on fusion Check all that apply. A.energy production in the sun B.energy production in nuclear reactors C.the hydrogen bomb D.energy production from fuel cells?
Last Answer : It's A and C. The sun and most other stars are fusion reaction engines, and hydrogen bomb (perhaps more properly a fusion nuclear weapon) apply nuclear fusion to do what they do.
Last Answer : Need answer
Description : All forms of immunity depend on an exposure to antigens and a subsequent response by _____ cells. a. basophil b. neutrophil c. NK d. T
Last Answer : d. T
Description : Lysozyme that is present in perspiration, saliva and tears, destroys (a) certain types of bacteria (b) all viruses (c) most virus-infected cells (d) certain fungi.
Last Answer : (a) certain types of bacteria
Description : Carbohydrates, the most abundant biomolecule on earth, are produced by (a) some bacteria, algae and green plant cells (b) fungi, algae and green plant cells (c) all bacteria, fungi and algae (d) viruses, fungi and bacteria.
Last Answer : (a) some bacteria, algae and green plant cells
Description : Which is correct about cell theory in view of current status of our knowledge about cell structure? (a) It needs modification due to discovery of subcellular structures like chloroplasts and ... Cell theory means that all living objects consists of cells whether or not capable of reproducing
Last Answer : (c) Cell theory does not hold good because all living beings (e.g., viruses) do not have cellular organisation.
Description : Retroviruses are so-named because their reverse transcriptase _____. a. reverses the flow of genetic information by stimulating information to proceed from RNA to DNA. b. reverses the normal ... the action of drugs on viruses and allows them to continue multiplying in living cells.
Last Answer : a. reverses the flow of genetic information by stimulating information to proceed from RNA to DNA.
Description : Attenuated viruses are those that _____. a. can be used to treat viral disease. b. give rise to viroids and prions. c. multiply in cells but at a low rate. d. have been treated with chemicals such as formaldehyde.
Last Answer : c. multiply in cells but at a low rate.
Description : Transposons are of particular significance because they a. often contain genes for antibiotic resistance. b. inhibit the effects of overlapping genes. c. come in pairs and often are associated with viruses. d. regulate gene transcription in bacterial cells.
Last Answer : a. often contain genes for antibiotic resistance.
Description : Which classification would include prokaryote cells that live in extreme conditions like hot springs and the Dead sea? a. Bacteria b. Fungi c. Viruses d. Archaea
Last Answer : d. Archaea
Description : The AIDS viruses specifically attack which kind of cell? a) B cells b) helper T cells c) killer T cells d) macrophages
Last Answer : ANSWER: B -- HELPER T CELLS
Description : What benefits did the ancient endosymbionts get from their host cells?
Description : The following statement(s) is/are true concerning host defense mechanisms to intraabdominal infection. a. Bacterial clearance can occur via translymphatic absorption b. Phagocytic activity and bacterial killing can ... may be walled off but are seldom sealed by the omentum and other mobile viscera
Last Answer : Answer: a, b, c The introduction of microorganisms into the normally sterile peritoneal environment invoke several potent specialized host antimicrobial defense mechanisms. Bacterial clearance, ... the contaminated enteric contents walled off, preventing continued soilage of the peritoneal cavity
Description : Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and ... effects on the host d. Each specific cytokine is produced by a single cell type
Last Answer : Answer: c Macrophages, endothelial cells, lymphocytes, and other cells secrete a large number of different compounds, termed cytokines, that are most probably evolved for the purpose of ... host defenses, exerting both salutatory and deleterious effects on the host, has become increasingly evident
Description : Which of the following statements are true of the multiple organ dysfunction syndrome (MODS)? A. The two-hit model proposes that secondary MODS may be produced when even a relatively ... intensive care units has decreased owing to increased awareness, prevention, and treatment of the syndrome.
Last Answer : Answer: ABC DISCUSSION: MODS is part of a clinical continuum that begins with the systemic inflammatory response syndrome, which is the host's stress response to any major insult such ... pathogenesis of MODS, the incidence of MODS continues to increase without a significant improvement in outcome
Description : An eazyme produced by HIV that allows the integration of HIV DNA into the host cell's DNA is (1) Ligase (2) Integrase (3) Helicase (4) DNA gyrase
Last Answer : (2) Integrase Explanation: HIV's enzyme for inserting the DNA version of its genome into the host cell DNA is called its "integrase". HIV-1 integrase catalyzes the "cut-and-paste" action of ... to the clipped ends. It is also produced by viruses containing double-stranded DNAs for the same purpose.
Description : Tobacco plants resistant to a nematode have been developed by the introduction of DNA that produces (in the host cells) (a) both sense and anti-sense RNA (b) a particular hormone (c) an antifeedant (d) a toxic protein.
Last Answer : a) both sense and anti-sense RNA
Description : At which stage of HIV infection does one usually show symptoms of AIDS? (a) Within 15 days of sexual contact with an infected person (b) When the infected retro virus enters host cells (c) ... large number of helper T - lymphocytes (d) When the viral DNA is produced by reverse transcriptase
Last Answer : (c) When HIV damages large number of helper T - lymphocytes
Description : The stomach is a chemical barrier to infection because the stomach a. Contains bile. b. Harbors helicobacterpylori, a member of the host microbiota. c. Possesses defensive cells. d. Has an acid ph.
Last Answer : d. Has an acid ph.
Description : Which one of the following statements applies to smallpox? a. The disease is associated with animal contact. b. The disease has been eradicated worldwide. c. It can be sexually-transmitted. d. The virus can lie dormant in host cells.
Last Answer : b. The disease has been eradicated worldwide.
Description : Which one of the following statements is NOT correct concerning the reproductive cycle of Chlamydia? a. Reticulate Bodies Are Infectious. b. Reticulate Bodies Reorganize Into Elementary Bodies. c. Elementary Bodies Infect Host Cells. d. Elementary Bodies Transform Into Reticulate Bodies.
Last Answer : a. Reticulate Bodies Are Infectious.
Description : During the process of lysogeny _____. a. Phage DNA Integrates Into The Bacterial Chromosome. b. A Bacterium Acquires DNA From The External Environment. c. Competent Cells Receive Plasmids. d. New Phage Particles Are Assembled In The Host Bacterium.
Last Answer : a. Phage DNA Integrates Into The Bacterial Chromosome.
Description : The first step in infection of a host bacterial cells by a phage is A- adsorption B- absorption C- penetration D- replication
Last Answer : adsorption
Description : Which of the following responses identifies a role of T lymphocytes? a) Transplant rejection Transplant rejection and graft-versus-host disease are cellular response roles of T cells. ... ) Bacterial phagocytosis and lysis Bacterial phagocytosis and lysis are humoral response roles of Blymphocytes.
Last Answer : a) Transplant rejection Transplant rejection and graft-versus-host disease are cellular response roles of T cells.
Description : Mammalian cells are not inhibited by low concentrations of tetracyclines that inhibit sensitive microorganisms because: A. Host cells lack active transport mechanism for tetracyclines B. Host cells actively pump out ... host cells has low affinity for tetracyclines D. Both A' and C' are correct
Last Answer : D. Both ‘A’ and ‘C’ are correct
Description : An eazyme produced by HIV that allows the integration of HIV DNA into the host cell’s DNA is : (1) Ligase (2) Integrase (3) Helicase (4) DNA gyrase
Last Answer : Integrase