Monday, October 1, 2012
محمد حماقي - ندمان 2012 | النسخة الاصلية
------------------------------------------Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Practice MCQ
| 1. In recombinant DNA technology a plasmid vector is cleaved by (A) Modified DNA ligase (B) A heated alkaline solution (C) The same enzyme that cleave the donor DNA (D) The different enzyme other than that cleave the donor DNA | Answer: (C) |
| 2. The most common plasmid vector used in genetic engineering is (A) PBR 328 (B) PBR 322 (C) PBR 325 (D) PBR 330 | Answer: (B) |
| 3. ‘Nif gene’ for nitrogen fixation is cereal crops like wheat, jowar etc. is introduced by cloning (A) Rhizobium meliloti (B) Bacillus thuringiensis (C) Rhizopus (D) Rhizophora | Answer: (A) |
| 4. Eco RI is an (A) Ligase (B) Polymerase (C) Restriction enzyme (D) Gyrase | Answer: (C) |
| 5. The transgenic plant flavr savr tomato carries an artificial gene for (A) Delay ripening process (B) Longer shell life (C) Added flavours (D) All of these | Answer: (D) |
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Genetic Basis of Inheritance-5
41. An inborn error of metabolism which eventually affects mental development is
a)Albinism
b)Phenylketonuria
c)Anaemia
d)Bleeder’s disease
a)Albinism
b)Phenylketonuria
c)Anaemia
d)Bleeder’s disease
42. Male is haploid in
a)Lizard
b)Cockroach
c)Honey bee
d)Bats
a)Lizard
b)Cockroach
c)Honey bee
d)Bats
43. Klinefelter’s syndrome has number of chromosomes
a)47
b)46
c)45
d)44
a)47
b)46
c)45
d)44
44. One gene one enzyme hypothesis was proposed by
a)Jacob and Monod
b)Beadle and Tatum
c)Watson and Crick
d)Garrod and Jensen
a)Jacob and Monod
b)Beadle and Tatum
c)Watson and Crick
d)Garrod and Jensen
45. DNA replication is
a)Conservative and discontinuous
b)Semiconservative and semidiscontinuous
c)Semiconservative and discontinuous
d)Conservative
a)Conservative and discontinuous
b)Semiconservative and semidiscontinuous
c)Semiconservative and discontinuous
d)Conservative
46. Experimental material in the study of DNA replication has been
a)Escherichia coli
b)Neurospora crassa
c)Pneumococcus
d)Drosophila melanogaster
a)Escherichia coli
b)Neurospora crassa
c)Pneumococcus
d)Drosophila melanogaster
47. Nuclcotide arrangement in DNA can be seen by
a)X-ray crystallography
b)Electron microscope
c)Ultracentrifuge
d)Light microscope
a)X-ray crystallography
b)Electron microscope
c)Ultracentrifuge
d)Light microscope
48. A DNA with unequal nitrogen bases would most probably be
a)Single stranded
b)Double stranded
c)Triple stranded
d)Four stranded
a)Single stranded
b)Double stranded
c)Triple stranded
d)Four stranded
49. Transcription involves synthesis of
a)DNA
b)tRNA
c)mRNA
d)rRNA
a)DNA
b)tRNA
c)mRNA
d)rRNA
50. DNA tempalte sequence of CTGATAGC is transcribed over mRNA as
a)GUCTUTCG
b)GACUAUCG
c)GAUTATUG
d)UACTATCU
a)GUCTUTCG
b)GACUAUCG
c)GAUTATUG
d)UACTATCU
Answer
41B,42C,43A,44B,45B,46A,47A,48A,49C,50B
41B,42C,43A,44B,45B,46A,47A,48A,49C,50B
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Genetic Basis of Inheritance-4
31. A colour blind daughter is born in case of
a)colour blind mother, normal father
b)carrier mother, colour blind father
c)Normal mother, colour blind father
d)carrier mother, normal father
a)colour blind mother, normal father
b)carrier mother, colour blind father
c)Normal mother, colour blind father
d)carrier mother, normal father
32. Euploidy is
a)one chromosome more than haploid set
b)one chromosome more than diploid set
c)one chromosome less than haploid set
d)Excat multiple of haploid set of chromosomes
a)one chromosome more than haploid set
b)one chromosome more than diploid set
c)one chromosome less than haploid set
d)Excat multiple of haploid set of chromosomes
33. Exchange of one part of a chromosome with a part of the same or another chromosome is
a)Inversion
b)crossing over
c)Translocation
d)Nucleolus
a)Inversion
b)crossing over
c)Translocation
d)Nucleolus
34. Determination of percentage of crossing over between two linked genes is important in
a)maintaining heterozygosity in population
b)indicating relative position of genes in chromosomes
c)fixation of heterosis in organisms
d)explaining the phenomenon of coupling and repulsion
a)maintaining heterozygosity in population
b)indicating relative position of genes in chromosomes
c)fixation of heterosis in organisms
d)explaining the phenomenon of coupling and repulsion
35. In Drosophila, XXY is female. In humans it represents an abnormal male because
a)Y-Chromosome induces male traits in humans
b)Y-chromosome is essential for female sex in Drosophila
c)Y-chromosome is not essential for male sex in humans
d)none of these
a)Y-Chromosome induces male traits in humans
b)Y-chromosome is essential for female sex in Drosophila
c)Y-chromosome is not essential for male sex in humans
d)none of these
36. A woman has a child with Klinefelter’s syndrome. Number of barr bodies present in the child is
a)one
b)Two
c)three
d)None
a)one
b)Two
c)three
d)None
37. Genes exclusively present on Y-chromosome are called
a)sex-linked
b)Holandric
c)Hologynic
d)Histone
a)sex-linked
b)Holandric
c)Hologynic
d)Histone
38. In humans, Philadelphia chromosome formed by reciprocal translocation between chromosomes
a)9 and 21
b)9 and 22
c)9 and 20
d)20 and 10
a)9 and 21
b)9 and 22
c)9 and 20
d)20 and 10
39. According to genetic balance theory, X/A=1.5 will make the individual
a)Male
b)Metafemale
c)Intersex
d)None of the above
a)Male
b)Metafemale
c)Intersex
d)None of the above
40. Number of barr bodies in XXXX female would be
a)4
b)3
c)2
d)1
a)4
b)3
c)2
d)1
Answer
31B,32D,33C,34B,35A,36A,37B,38B,39B,40B
31B,32D,33C,34B,35A,36A,37B,38B,39B,40B
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Genetic Basis of Inheritance-3
21. Recessive mutations are expressed in
a)Homozygous condition
b)Heterozygous condition
c)Next generation
d)Same generation
a)Homozygous condition
b)Heterozygous condition
c)Next generation
d)Same generation
22. Which one can induce polyploidy?
a)Colchicine
b)Acridines
c)Ethylene
d)Maleic hydrazide
a)Colchicine
b)Acridines
c)Ethylene
d)Maleic hydrazide
23. Harmful mutations do not get eliminated from gene pool because
a)They have survival value
b)Genetic drift
c)They are formed repeatedly
d)They are recessive and carried by heterozygous individuals
a)They have survival value
b)Genetic drift
c)They are formed repeatedly
d)They are recessive and carried by heterozygous individuals
24. If haploid chromosome number is 10, the monosomic number shall be
a)9
b)18
c)10
d)19
a)9
b)18
c)10
d)19
25. A normal green male Maize is crossed with albino female. The progeny is albino is albino because
a)Trait for albinism is dominant
b)The albinos have biochemical to destroy plastids derived from green male
c)Plastids are inherited from female parent
d)Green plastids of male must have mutated
a)Trait for albinism is dominant
b)The albinos have biochemical to destroy plastids derived from green male
c)Plastids are inherited from female parent
d)Green plastids of male must have mutated
26. Which crop variety is not due to induced mutations?
a)Reimei of rice
b)Prabhat of Arhar
c)Sharbati sonora of wheat
d)Aruna of castor
a)Reimei of rice
b)Prabhat of Arhar
c)Sharbati sonora of wheat
d)Aruna of castor
27. Smallest segment of genetic material affected by mutation is
a)Recon
b)Cistron
c)Muton
d)Exon
a)Recon
b)Cistron
c)Muton
d)Exon
28. Triticum aestivum (bread wheat) is
a)Tetraploid
b)Hexaploid
c)Diploid
d)Haploid
a)Tetraploid
b)Hexaploid
c)Diploid
d)Haploid
29. Which one is de novo mutation?
a)TT×TT→TT
b)tt×tt→Tt
c)Tt×tt→Tt
d)Tt×Tt→TT,Tt,tt
a)TT×TT→TT
b)tt×tt→Tt
c)Tt×tt→Tt
d)Tt×Tt→TT,Tt,tt
30. If BB represents barr body and Y0Y−body, XXY or Klinefelters syndrome has
a)BB-1,Y0−0
b)BB-1,Y0-1
c)BB-0,Y0-1
d)BB-2,Y0-1
a)BB-1,Y0−0
b)BB-1,Y0-1
c)BB-0,Y0-1
d)BB-2,Y0-1
Answer
21A,22A,23D,24D,25C,26D,27C,28B,29B,30B
21A,22A,23D,24D,25C,26D,27C,28B,29B,30B
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Genetic Basis of Inheritance
11. Turner’s syndrome is characterised by chromosomes
a)46
b)45
c)47
d)48
a)46
b)45
c)47
d)48
12. Nucleosome core is made of
a)H1,H2A, H2B and H3
b)H1,H2A, H2B, H3 and H4
c)H1, H2A, H2B, H4
d)H2A, H2B, H3 and H4
a)H1,H2A, H2B and H3
b)H1,H2A, H2B, H3 and H4
c)H1, H2A, H2B, H4
d)H2A, H2B, H3 and H4
13. In human beings 45 chromosomes/single X/XO abnormality causes
a)Down’s syndrome
b)Klinefelter’s syndrome
c)Turner’s syndrome
d)Edward’s syndrome
a)Down’s syndrome
b)Klinefelter’s syndrome
c)Turner’s syndrome
d)Edward’s syndrome
14. Sex of a child is due to
a)size of ovum
b)Health of father
c)Sex chromosome of father/sperm
d)Sex chromosome of mother/ovum
a)size of ovum
b)Health of father
c)Sex chromosome of father/sperm
d)Sex chromosome of mother/ovum
15. Diploid chromosome number in humans is
a)46
b)44
c)48
d)42
a)46
b)44
c)48
d)42
16. In a dihybrid cross, two recessive genes showed 10% recombinants. The distance between two genes is
a)10 map units
b)20 map units
c)30 map units
d)40 map units
a)10 map units
b)20 map units
c)30 map units
d)40 map units
17. Sex linked characters are generally
a)Lethal
b)recessive
c)dominant
d)not inherited
a)Lethal
b)recessive
c)dominant
d)not inherited
18. Trisomy has chromosome complement of
a)2n-1
b)2n-1-1
c)2n+1+1
d)2n+1
a)2n-1
b)2n-1-1
c)2n+1+1
d)2n+1
19. Muller was awarded Nobel prize in 1946 for his work on
a)Protein synthesis
b)chemistry of nucleic acids
c)cancer
d)X-ray induced mutations
a)Protein synthesis
b)chemistry of nucleic acids
c)cancer
d)X-ray induced mutations
20. Mutations used in agriculture are commonly
a)Induced
b)spontaneous
c)Lethal
d)recessive and lethal
a)Induced
b)spontaneous
c)Lethal
d)recessive and lethal
Answer
11B,12D,13C,14C,15A,16A,17B,18D,19D,20A
11B,12D,13C,14C,15A,16A,17B,18D,19D,20A
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Genetic Basis of Inheritance – Competative exam questions Part – 1
1. A cross between homozygous recessive and heterozygous plant is
a)Monohybrid cross
b)Dihybrid cross
c)Test cross
d)Back cross
a)Monohybrid cross
b)Dihybrid cross
c)Test cross
d)Back cross
2. In Red-white flowered cross of Mirabilis jalapa, F2 generation has red, pink and white flowered plants in the ration of
a)1:2:1
b)1:0:1
c)2:1:1
d)1:1:2
a)1:2:1
b)1:0:1
c)2:1:1
d)1:1:2
3. A blue fowl obtained from mating between black and white fowls, is self-crossed. The F2 ratio is
a)1 black:2 white: 1 blue
b)2 black: 1 white: 1 blue
c)1 black: 2 blue :1white
d)none of these
a)1 black:2 white: 1 blue
b)2 black: 1 white: 1 blue
c)1 black: 2 blue :1white
d)none of these
4. Epistasis in which dihybrid ratio of 9:3:3:1 between Aa Bb ×AaBbis modified is
a)dominance of one allele on another allele at the same locus
b)dominance of one allele on another allele at both its loci
c)interaction of two alleles at different loci
d)interaction between two alleles at same locus
a)dominance of one allele on another allele at the same locus
b)dominance of one allele on another allele at both its loci
c)interaction of two alleles at different loci
d)interaction between two alleles at same locus
5. Which amino acid is substituted in sickle cell anaemia
a)Glutamic acid by valine in α−chain
b)Glutamic acid by valine in β−chain
c)Valine by glutamic acid in β−chain
d)Valine by glutamic acid in α−chain
a)Glutamic acid by valine in α−chain
b)Glutamic acid by valine in β−chain
c)Valine by glutamic acid in β−chain
d)Valine by glutamic acid in α−chain
6. Mendel found certain traits not ti assort independently. It is due to
a)dominance
b)linkage
c)crossing over
d)amitosis
a)dominance
b)linkage
c)crossing over
d)amitosis
7. If Mendel had studied 7 traits using a plant with 12 chromosomes instead of 14, he would have
a)discovered incomplete dominance
b)not discovered the law of independent assortment
c)discovered sex linkage d)mapped the chromosome
a)discovered incomplete dominance
b)not discovered the law of independent assortment
c)discovered sex linkage d)mapped the chromosome
8. Crossing over in diploid organisms is responsible for
a)Dominance of genes
b)Linkage between genes
c)Recombination of linked genes
d)segregation of alleles
a)Dominance of genes
b)Linkage between genes
c)Recombination of linked genes
d)segregation of alleles
9. Huntington’s chorea appears at the age of
a)25-55 years
b)15-25 years
c)50-60 years
d)10-15 years
a)25-55 years
b)15-25 years
c)50-60 years
d)10-15 years
10. Persons with Klinefelter’s syndrome have chromosomes
a)XX
b)XY
c)XXY
d)XYY
a)XX
b)XY
c)XXY
d)XYY
Answer
1C,2A,3C,4B,5B,6B,7B,8C,9A,10C
1C,2A,3C,4B,5B,6B,7B,8C,9A,10C
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Short question
| 1. | LSD is derived from | Argot fungus |
| 2. | Valium is a | Tranquilliser |
| 3. | Psychosis is | Mental illness |
| 4. | BCG is used against | Tuberculosis |
| 5. | Rh-factor was first discovered in | Monkey |
| 6. | Myocardial infarction is a disease of | Heart |
| 7. | Who received Nobel Prize for peace for his work on wheat and rice? | Norman Bourlog |
| 8. | Who is the author of ‘Historia Plantarum” | Theophrastus |
| 9. | A dicot plant without cotyledons is called | Dodder Plant (Cuscuta) |
| 10. | The branch of biology which deals with identification of disease and its pathogen is | Patholog |
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Practice
| 1. The enzyme DNA polymerase can work only in (A) 3¢ ® 5¢ direction (B) 5¢ ® 3¢ direction (C) Both the direction (D) 5¢ ® 5¢ direction | Answer: (B) |
| 2. Enzyme required for removing RNA primer during DNA replication is (A) DNA primase (B) DNA ligase (C) DNA polymerase I (D) DNA polymerase III | Answer: (C) |
| 3. During DNA replication, the reunion or recoiling of separated DNA strand is prevented by (A) Helix destabilizing protein (B) Single strnad binding protein (C) Rep protein (D) Both (A) and (B) | Answer: (D) |
| 4. The enzyme that cuts the bonds of DNA molecule at the origin of replication is (A) Endonuclease (B) DNA polymerase (C) DNA gyrase (D) DNA ligase | Answer: (A) |
| 5. Which of the following enzyme is required to release the tension imposed by uncoiling of strands? (A) Endonuclease (B) DNA ligase (C) DNA gyrase (D) DNA helicase | Answer: (C) |
| 6. The cellular composition of m-RNA is (A) 5-10% (B) 3-5% (C) 10-20 % (D) 70-80% | Answer: (B) |
| 7. Formation of mRNA from DNA is called (A) Transformation (B) Transduction (C) Traslation (D) Transcription | Answer: (D) |
| 8. The ratio of purines and pyrimidines in mRNA is not 1:1 because the nitrogenous bases are (A) Unpaired (B) Paired (C) Paired only in loops (D) Paired in stems | Answer: (A) |
| 9. The codons which may present at 3¢ end of mRNA (A) UAA (B) UAG (C) UGA (D) Any one of these | Answer: (D) |
| 10. Which of the following is not tool of genetic engineering? (A) Vectors (B) Enzymes (C) Foreign DNA (D) GMO | Answer: (D) |
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
ustream.tv/channel/ehab-aboueladab
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
طلاب وطالبات مدرسة الراهبات الفرنسيسكانيات بدمياط
------------------------------------------
Best Wishes:
Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com
------------------------------------------
Franciscan nun.damitta
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
تقرير : ماذا حصل حتى الأن بين أبل و سامسونج في المحكمة - عالم التقنية | عالم التقنية
تقرير : ماذا حصل حتى الأن بين أبل و سامسونج في المحكمة - عالم التقنية | عالم التقنية
------------------------------------------Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
------------------------------------------Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
أبل تملك قيمة سوقيه أكثر من مجموع قيمة مايكروسوفت وامازون وفيس بوك وجوجل - عالم التقنية | عالم التقنية
أبل تملك قيمة سوقيه أكثر من مجموع قيمة مايكروسوفت وامازون وفيس بوك وجوجل - عالم التقنية | عالم التقنية
------------------------------------------Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
------------------------------------------Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
GRE Biology Practice Test: Proteins
1. 4-hydroxy proline is present in
a) Collagen
b) Plant cell wall
c) Keratin
d) Both plant cell wall and collagen
2. Peptide bonds between amino acids are highly stable and have a half-life of seven years in intracellular condition. This is due to
a) High activation energy required for hydrolysis
b) Low activation energy required for hydrolysis
c) Peptide bond is a covalent bond
d) Peptide bond is rigid and planar
3. Tri-peptide consists
a) 3 amino acids and 3 peptide bonds
b) 2 amino acids and 3 peptide bonds
c) 3 amino acids and 2 peptide bonds
d) 3 amino acids and 4 peptide bonds
4. All the following statements are true except
a) Ornithine and citrulline are uncommon aminoacids
b) Ornithine is an intermediates in Urea cycle
c) Ormithine and citrulline are uncommon amino acids present in many proteins
d) Both ornithine and citrulline are intermediates in urea cycle
5. The characteristic strong absorbance of 280nm of proteins is due to
a) All amino acids can absorb at 280nm
b) Only Tryptophan and tyrosine can absorb at 280 nm
c) Tryptophan is responsible for the absorbance
d) Tryptophan, tyrosine and phenylalanine can absorb at 280 nm
6. The formation of cystine occurs at
a) ER
b) Golgi
c) Cytosol
d) Mitochondria
7. Which of the following interaction contributes most in protein folding
a) Covalent bond
b) Ionic bond
c) Hydrophobic interaction
d) Vander walls interaction
8. Which of the following aminoacid has pKa near neutrality
a) Tryptophan
b) Arginine
c) Histidine
d) Asparagine
9. Desmosine is an unusual amino acid found in
a) Myosin
b) Elastin
c) Troponin
d) Actin
10. How many small peptides are formed upon cleavage by trypsin if a protein has 5 lysine residues
a) 4
b) 5
c) 6
d) 7
11. EF-1α and EF-Tu are
a) Analogs
b) Homologs
c) Paralogs
d) Syllogs
12. All the statements regarding peptide bond are true except
a) Peptide bond is a co-valent bond
b) Peptide bond is rigid and planar
c) Peptide bond has partial double bond character
d) Peptide bond is formed by non-condensation reaction
13. Αlpha-helix has
a) 3.6 residues/turn and is a right handed helix
b) 3.8 residues/turn and is a right handed helix
c) 3.6 residues/turn and is a left handed helix
d) 3.8 residues/turn and is a left handed helix
14.Which of the following amino acids are rarely present in alpha helix
a) Glycine and proline
b) Proline and tryptophan
c) Tryptophan and glycine
d) Proline only
15. PDI is an enzyme involve in
a) Protein synthesis
b) Protein degradation
c) Protein folding
d) Protein quaternery structure formation
Answers with explanation
1-d)
Both plant cell wall and collagen
Explanation: 4-hydroxyproline, 5-hydroxy lysine, selenocysteine, desmosine, carboxy glutamate all are uncommon amino acids
2-a)
3-c)
amino acids and 2 peptide bonds
4-c)
Ormithine and citrulline are uncommon amino acids present in many proteins
Remember, these two amino acids are not present in any proteins.
5-d
Tryptophan, tyrosine and phenylalanine can absorb at 280 nm. These are aromatic amino acids. Tryptophan and tyrosine absorbs strongly at 280nm where as phenylalanine has comparatively low absorbance.
6-a) ER.
Two cysteine amino acids are linked by di-sulphide bond to form cystine. Di-sulphide bonds are formed only in the highly oxidizing environment of ER.
7-c Hydrophobic interaction
8-c histidine has a pKa of 6.0 and has buffering capacity
9-b) Elastin
10-c) 6 Trypsin cleave at C-terminal of lysine or arginine residue
11-b) homologs.
EF-Tu elongation factor is involved in protein synthesis of bacteria. The protein counterpart in eukaryote is EF-1α. Both are members of the same family with a common ancestry.
12-d Peptide bond is formed by non-condensation reaction. Actually Peptide bond is formed by condensation reaction.
13-a) 3.6 residues/turn and is a right handed helix in all proteins. You have to read the options carefully before picking one.
14-a) glycine and proline.
Proline is an alpha helix terminator as it cannot form H- bond with other residues. Glycine is the simplest amino acid and has high conformational flexibility. Polymers of glycine form coiled structures entirely different from alpha helix.
15-c
PDI (protein di sulphide isomerase) is an enzyme involved in shuffling of di sulphide bonds in protein folding. Refer our post protein folding.
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
GRE Practice Test : Cytology - Plasma membrane
1. Steroid hormones have receptors predominantly on
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
a) cell surface
b) cytoplasm
c) both cell surface and cytoplasm
d) inside nucleus only
2. The major interaction responsible for stabilising plasma membrane
a)hydrophilic interactions
b)covalent bonds
c)ionic bonds
d)hydrophobic interactions
3. The organelles involved in protein transport
a)ER and Golgi
b)ER and mitochondria
c)Golgi and mitochondria
d) lysosomes and golgi
4. The role of carbohydrates in cell membrane
a) cell adhesion
b) cell-cell recognition
c) assisting transport across cell membrane
d) cell storage reserve
5. All hormones can cross plasma membrane except
a) Estrogen
b) insulin
c) progesterone
d) thyroxine
6. The major biomolecule responsible for selective uptake of materials across plasma membrane
a) Carbohydrate
b)protein
c) lipids
d)phospholipids
7. All the following substance pass through cell membrane except
a) O2
b)H2O
c)CO2
d)H+
8. At physiological pH increase in cholesterol level
a) increases fluidity
b)decreases fluidity
c) no change in fluidity
d) none of the above
9) The longer the fatty acid chain, fluidity of the lipid bi layer
a) increases
b)decreases
c) no change in fluidity
d) none of the above
10. The inner leaflets of erythrocytes has
a) sphingomyelin and phosphatidylcholine
b) phosphatidylserine and phosphatidylethanolamine.
c) sphingomyelin and phosphatidylserine
d) phosphatidyl serine and phosphatidylcholine
11. Lipid bi layer is
a) hydrophilic
b) hydrophobic
c) hydrophilic and hydrophobic
d) depends on the surrounding medium
12. Which of the following membrane has the largest amount of proteins
a) erythrocyte membrane
b) myelin sheath membrane
c) inner mitochondrial membrane
d) outer mitochondrial membrane
13. high lipid content is a characteristic of
a) erythrocyte membrane
b) myelin sheath membrane
c) inner mitochondrial membrane
d) outer mitochondrial membrane
14. The distribution of intrinsic proteins in the cell membrane is
a) symmetrical
b)assymetrical
c) random
d)uniform
15. In cell membrane, carbohydrates in glycoproteins or glycolipids are oriented
a) towards outside
b)towards inside
c) towards outside and inside
d)randomly distributed
16. The plasma membrane is impermeable to all molecules except
a) Glucose
b) ATP
c)rea
d)K+
17. The erythrocyte glucose transporter is an example of
a)simple diffusion
b)active transport
c) facilitated diffusion
d)ion driven active transport
18. Which of the following transport induces conformational change in protein
a)simple diffusion
b)active transport
c) facilitated diffusion
d)ion driven active transport
19. Na+ glucose transporter is an example of
a) facilitated diffusion
b)ATP driven active transport
c)Symport
d)antiport
20. Clathrin coated pits are associated with
a) phagocytosis
b)pinocytosis
c)receptor mediated endocytosis
d)exocytosis
Answers
1. b) cytoplasm
2. d)hydrophobic interactions
3. a)ER and Golgi
4. b) cell-cell recognition
5. b) insulin
6. b)protein
7. d)H+
8. b)decreases fluidity
9. b)decreases
10.b) phosphatidylserine and phosphatidylethanolamine.
11.c) hydrophilic and hydrophobic
12.c) inner mitochondrial membrane
13. b) myelin sheath membrane
14. b)assymetrical
15. a) towards outside
16. c) urea
17. c) facilitated diffusion
18. c) facilitated diffusion
19. c)Symport
20. c)receptor mediated endocytosis
------------------------------------------ Best Wishes: Dr.Ehab Aboueladab, Tel:01007834123 Email:ehab10f@gmail.com,ehababoueladab@yahoo.com ------------------------------------------
Subscribe to:
Posts (Atom)