Description : Some viruses have RNA but no DNA. This would indicate that – (1) these viruses cannot replicate (2) these viruses have no heritable information (3) RNA transmits the hereditary information in these viruses (4) their nucleic acids can be crystallised
Last Answer : (2) these viruses have no heritable information Explanation: DNA is an informational molecule encoding the genetic instructions Along with RNA and proteins, it is one of the three major macromolecules that are ... guanine, adenine, thymine, and cytosine) recorded using the letters G, A, T, and C.
Description : Which is wrong about nucleic acids? (a) DNA is single stranded in some viruses. (b) RNA is double stranded occasionally. (c) Length of one helix is 45 Å in B-DNA. (d) One turn of Z-DNA has 12 bases
Last Answer : (c) Length of one helix is 45 Å in B-DNA
Description : Viruses are no more “alive” than isolated chromosomes because (a) they require both RNA and DNA (b) they both need food molecules (c) they both require oxygen for respiration (d) both require the environment of a cell to replicate.
Last Answer : (d) both require the environment of a cell to replicate.
Description : Which one of the following statements about viruses is correct? (a) Viruses possess their own metabolic system. (b) All viruses contain both RNA and DNA. (c) Viruses are obligate parasites. (d) Nucleic acid of viruses is known as capsid.
Last Answer : (c) Viruses are obligate parasites.
Description : Which of the following is not a natural polymer? (A) Nucleic acids e.g. RNA and DNA (B) Polysaccharides (C) Polyisoprene (D) Polyurethane
Last Answer : (D) Polyurethane
Description : Nissl’s bodies are mainly composed of (a) proteins and lipids (b) DNA and RNA (c) nucleic acids and SER (d) free ribosomes and RER.
Last Answer : (d) free ribosomes and RER.
Description : Nissl bodies are mainly composed of (1) Proteins and lipids (2) DNA and RNA (3) Nucleic acids and SER (4) Free ribosomes and RER
Last Answer : (4) Free ribosomes and RER
Description : Which statement is wrong for viruses? (a) All are parasites. (b) All of them have helical symmetry. (c) They have ability to synthesize nucleic acids and proteins. (d) Antibiotics have no effect on them
Last Answer : (b) All of them have helical symmetry
Description : 100. Which statement is wrong for viruses ? (1) Antibiotics have no effect on them (2) All are parasites (3) All of them have helical symmetry (4) They have ability to synthesize nucleic acids and proteins
Last Answer : All of them have helical symmetry
Description : The only molecule in the living world that can replicate itself is (a) DNA (b) RNA (c) Both DNA and RNA (d) Neither DNA nor RNA
Last Answer : Ans:(a)
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 : Select the wrong statement. (a) The term ‘contagium vivum fluidum’ was coined by M. W. Beijerinck. (b) Mosaic disease in tobacco and AIDS in human being are caused by viruses. (c) The viroids were discovered by D.J. Ivanowsky. (d) W.M. Stanley showed that viruses could be crystallised.
Last Answer : (c) The viroids were discovered by D.J. Ivanowsky
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 : The hereditary material present in the bacterium E.coli is (a) single-stranded DNA (b) double-stranded DNA (c) DNA (d) RNA.
Last Answer : (b) double-stranded DNA
Description : Orcinol method is employed in the quantitation of (A) Nucleic acid (B) DNA (C) RNA (D) Proteins
Last Answer : Answer : C
Description : Diphenylamine method is employed in the quantitation of (A) Nucleic acid (B) RNA (C) DNA (D) Proteins
Description : If in a nucleic acid there are more than 8000 nucleotides it is most likely (A) RNA (B) DNA (C) Both (A) and (B) (D) None of these
Last Answer : Answer : B
Description : Which of the following statements about nucleic acid is most correct? (A) Both pentose nucleic acid and deoxypentose nucleic acid contain the same pyrimidines (B) Both pentose nucleic acid and deoxypentose ... (C) RNA contains cytosine and thymine (D) DNA and RNA are hydrolysed by weak alkali
Description : True statements about the nucleic acid include: a. contains purine and pyrimidine which are bound together by covalent bonds b. there is always an equal concentration of purine and pyrimidine c. in RNA, ... d. introns is more common than exons on the DNA e. the histones mark the excision site
Last Answer : there is always an equal concentration of purine and pyrimidine
Description : Why do viruses replicate?
Last Answer : Need answer
Description : Satellite DNA is important because it (a) does not code for proteins and is same in all members of the population (b) codes for enzymes needed for DNA replication (c) codes for proteins ... and also the same degree of polymorphism in an individual, which is heritable from parents to children.
Last Answer : (d) shows high degree of polymorphism in population and also the same degree of polymorphism in an individual, which is heritable from parents to children
Description : A heritable change in DNA is called a ______. a. mistake b. mutation c. gene d. pathogen
Last Answer : b. mutation
Description : When RNA in hydrolysed there is no relationship among the quantities of four bases obtained like DNA. What does this fact indicate about structure of RNA ?
Last Answer : Ans. This indicate that RNA has a single strand structure.
Description : Which one of the following structural formulae of two organic compounds is correctly identified along with its related function? (a) B : Adenine - A nucleotide that makes up nucleic acids (b) A : Triglyceride - ... ) B : Uracil - A component of DNA (d) A : Lecithin - A component of cell membrane
Last Answer : (d) A : Lecithin - A component of cell membrane
Description : What is the weak bond holding the nucleic acids together in DNA? a. ionic bonds b. covalent bonds bonds c. polar bond d. hydrogen bond
Last Answer : d. hydrogen bond
Description : Production of a human protein in bacteria by genetic engineering is possible because (a) the human chromosome can replicate in bacterial cell (b) the mechanism of gene regulation is identical in ... ) bacterial cell can carry out the RNA splicing reactions (d) the genetic code is universal.
Last Answer : (d) the genetic code is universal.
Description : Transfer RNA transfers (A) Information from DNA to ribosomes (B) Information from mRNA to cytosol (C) Amino acids from cytosol to ribosomes (D) Proteins from ribosomes to cytosol
Description : 9 In some viruses DNA is synthesized by using RNA as a template. Such a DNA is called............ a. r-DNA b. C-DNA c. B- DNA d. A- DNA
Last Answer : Ans. b C-DNA
Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oncogenes
Description : Template-directed DNA synthesis occurs in all the following except (A) The replication fork (B) Polymerase chain reaction (C) Growth of RNA tumor viruses (D) Expression of oneogenes
Description : The only correct statement about oncoviruses is (A) All the oncoviruses are RNA viruses (B) Reverse transcriptase is present in all oncoviruses (C) Viral oncogenes are identical to human protooncogens (D) Both DNA and RNA viruses can be oncoviruses
Last Answer : Answer : D
Description : All of the following statements about RNA-dependent DNA polymerase are true except: (A) It synthesizes DNA using RNA as a template (B) It is also known as reverse transcriptase (C) It synthesizes DNA in 5’→3’ direction (D) It is present in all the viruses
Description : Most viruses that infect plant possess (a) single-stranded DNA (b) single-stranded RNA (c) double-stranded DNA and RNA (d) double - stranded RNA only
Last Answer : Ans:(b)
Description : Which of the following is true? (1) DNA is the genetic material in most of the organism (2) RNA is the genetic material in most viruses and bacteria (3) DNA is the genetic material in all the viruses (4) RNA is the genetic material in all the viruses
Last Answer : (1) DNA is the genetic material in most of the organism Explanation: Deoxyribonucleic acid (DNA) molecules are informational molecules encoding the genetic instructions used in the development and functioning of all ... letters. G, A, T, and C. DNA is well-suited for biological information storage.
Description : The chemical component that is invariably found in all viruses is (1) proteins (2) lipids (3) DNA (4) RNA
Last Answer : (1) proteins Explanation: All viruses contain the following two components: a nucleic acid genome and a protein capsid that covers the genome. Together this is called the nucleocapsid. The proteinous ... , many animal viruses contain a lipid envelope. The entire intact virus is called the virion.
Description : Virions are (a) DNA viruses (b) RNA viruses (c) Naked DNA viruses (d) Naked RNA viruses
Last Answer : (d) Naked RNA viruses
Description : .Viruses possess (a) ribosomes to synthesize protein (b) organelle for its vital mechanism (c) either DNA or RNA (d) none of these.
Last Answer : (c) either DNA or RNA
Description : Viruses have (a) DNA enclosed in a protein coat (b) prokaryotic nucleus (c) single chromosome (d) both DNA and RNA.
Last Answer : (a) DNA enclosed in a protein coat
Description : .Viroids differ from viruses in having (a) DNA molecules without protein coat (b) RNA molecules with protein coat (c) RNA molecules without protein coat (d) DNA molecules with protein coat
Last Answer : (c) RNA molecules without protein coat
Description : Viroids differ from viruses in having; (1) DNA molecules without protein coat (2) RNA molecules with protein coat (3) RNA molecules without protein coat (4) DNA molecules with protein coat
Last Answer : (3) RNA molecules without protein coat
Description : The chemical component that is invariably found in all viruses is : (1) proteins (2) lipids (3) DNA (4) RNA
Last Answer : proteins
Description : Which of the following is true ? (1) DNA is the genetic material in most of the organism (2) RNA is the genetic material in most viruses and bacteria (3) DNA is the genetic material in all the viruses (4) RNA is the genetic material in all the viruses
Last Answer : DNA is the genetic material in most of the organism
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.
Last Answer : They can multiply only in host cells
Description : Identify the correct statement with regard to G1 phase (Gap 1) of interphase. (a) DNA synthesis or replication takes place. (b) Reorganisation of all cell components takes place. (c) Cell is metabolically active, grows but does not replicate its DNA. (d) Nuclear division takes place.
Last Answer : (c) Cell is metabolically active, grows but does not
Description : Who proved that DNA not protein transmitted a full complement of hereditary information?
Last Answer : What is the answer ?
Description : Viruses are made up of – (1) Protein and lipids (2) Nucleic and protein (3) Lipids and carbohydrate (4) Carbohydrate and Nucleic acid
Last Answer : (2) Nucleic and protein Explanation: A virus is made up of a core of genetic material, either DNA or RNA, surrounded by a protective coat called a capsid which is made up of protein.
Description : Which of the following characteristics would not be used to classify viruses? A.Type of cell wall structure B.Type of nucleic acid C.Presence of an envelope D.Symmetry
Last Answer : A.Type of cell wall structure
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 : What is Mycology? A-Study of viruses B- Study of nucleic acid C- Study of bacteria D-Study of fungi
Last Answer : Study of fungi