Dvt Genetics

Question 1

Distance bw two base pairs in double stranded dna

Answer 1

0.34 nm

Question 2

Width of dna is

Answer 2

2nm

Question 3

Nucleosome bead

Answer 3

8 histone molecules 146 base pairs of dna

Question 4

Parts of chromosomes

Answer 4

Heterochromatin
More condensed ,silenced genes(methylated)
Gene poor (high AT comtent)
Stains darker
Euchromatin
Less condensed
Gene expressing
Gene rich(higher GC content)
Stains lighter

Question 5

Chargaffs rule

Answer 5

Applicable for double stranded dna
A pairs with T
G paira with C
Or
Number of purine equal to number of pyrimidines
Or
Ratio of purine bases and pyramidine bases is 1

Question 6

Denaturants for dna is

Answer 6

Heat
Denaturation occurs by increasing the temperature or decreasing the salt concentration
Tem fold increase in monovalent cation increases tm ( melting temp) by 16.6 degree celsius

Question 7

Human mitochondrial dna

Answer 7

Double stranded circular dna coming from ovum
16569 base pairs
Protein syntehsis
Codes for 13 protein that play a key role in electron transport chain

Question 8

Motochondrial dna is replicated by

Answer 8

DNA polymerase gama

Mutation very common

Question 9

Gentic code

Answer 9

Codon made up of 3 nucleotides
Read continuosly
Non overlaping
Degeneracy-multiple codon of same amino acid(due to wobbling-proposed by crick-base pairing may not be followed)
Unambiguous -
Universal (nearly)

Question 10

Donor of atoms for purine ring

Answer 10

Aspartate
N10 formyltetrahydrofolate
Amide nitrogen of glutamine
N5 n10 methenyk tetrahydrdolate
Glycine
Respiratory co2

Question 11

Salvage pathway. For purine aymthesis

Enzyme

Answer 11

Adenine phosphoribosyl transeferase
Hypocanthine guanine phosphoribosyl transferase
Hypoxanthine guanine phosphoribosyl transferase

Question 12

Final metabolic byproduct of Purine nucleotide metabolism

Answer 12

Uric acid

Question 13

Aource of atoms for pgramidine in denovo synthesis

Answer 13

Aspartate (major)
Ribose 5 phosphate
Co2
Glutamine

Question 14

Main emzyme of dna replication in prokaryotes

Answer 14

Dna polymerase 3

Question 15

Removal of rna primer removal and repair

Answer 15

Dna polymerase 1

Question 16

Kornberg enzyme and klenow fragment

Answer 16

Invented dna polymerase 1 holoenzyme

Large fragment klenow fragmnwt doesnt have 5-3 exonuclease activity

Question 17

Profucts of eukaryotic rna polymerase

Answer 17

Mrna
Most sn rna
Mi rna

Question 18

Product of eukaryotic rna polymerase 3

Answer 18

5 s rna
Trna
U6 sn Rna

Question 19

Product of eukaryotic rna polymerase 1

Answer 19

45 s pre rna

Question 20

Very sensitive rna polymerse to alphaamnitin

Answer 20

Rna polymerase 2
Rna polymerase 1 insensitive
Rna polymerase 3 moderately sensitive

Question 21

Core enzyme

Answer 21

Alpha2 beta beta prime and omega

Question 22

Foot pf rna polymerase in prokaryotes

Answer 22

Sigma factor identity the promoter of the gene and bind

Question 23

Post transcriptinal modification of hnRNA

Answer 23

1)Capping at 5 prime end-nuclear process transferred by guanylyk transferase
Methylation in cytosol by guanine 7 methyl transferase
2) poly A tail-40-250 adenine nucleotide attached to 3 prime end
Poluadenylate polymerase
3) splicing
Via spliceosome

Question 24

Mrna editing programme

Answer 24

Same gene produced Apo b 48. In intestinal cell and Apo b 100 in liver cells

Question 25

Dna repair defect inHNPCC

Answer 25

Mismatch defect

Question 26

Dna repair defect in Bloom syndrome

Answer 26

Helicase defect

Question 27

Dna repair defect in cockayne syndrome

Answer 27

Transcription coupled repair

Question 28

Dna repair defect in bteast cancer

Answer 28

Ss/ds break repair

Question 29

Dna repair defect in xeroderma pigmentosa

Answer 29

Nucleotide excision defect

Question 30

Non coding regulatory rna

Answer 30

1)Mi(micro) Rna single atarnded profuced by double starnded precusor endogenous 2)si RNA double stramded endogenous or exogenous Both are responsible for shutting of mrna gene knock down

Question 31

Moat commonly user restriction enzyme in various technologies

Answer 31

Type 2 enzymes

Question 32

Fish technology (flurescnese in aitu hybridization)

Answer 32

MoleculR cytogenetic technique which uses flouriscent probe which is complementary to the apecefic dna sequence

Question 33

Types of probes in fish techniques

Answer 33

Centromere probe Telomere probe Whole chromosome probe Locus probe-gene detection and localization,gene amplification,deletion,translocation

Question 34

Probe in fish may be

Answer 34

Ds dna probe Ss dna probe Rna probe Synthetic oligonucleotide probe

Question 35

Radioactive labellng of probe in FISH

Answer 35

32p 35S 3H

Question 36

Nonradioactive isotope labellimg in FISH

Answer 36

Biotin Fluorescent dye Digixigenin

Question 37

Application of FISH

Answer 37

1)Karyotyping-aneuploidy(trisomy,deletion of whole chromosome) Chronosomal aberration- deltion,duplication,translocation 2)developmental biology-gene expression profiling in embryonic tissue

Question 38

Microaray

Answer 38

..

Question 39

DNA sequencing by sanger

Answer 39

Di deoxynucleotide chain termination method

Question 40

Restriction fragment length polymorphism (RFLP)

Answer 40

Based on variation of the restriction site in an individual DNA which may result from polymorphism or mutation

Question 41

Polymorphism

Answer 41

Inherent variablity in the sequence of DNA Two types 1)SNP single nucleotide poly 2)VNTR variable nr of tantem repeat-minisatelikte and micro satelite

Question 42

RFLP uses

Answer 42

Disease diagnosis forensic investigations Paternity dispute

Question 43

Polymerase chain reaction

Answer 43

Kary mullis 1984 | Target and flanking sequence

Question 44

Components required for pcr

Answer 44

``` Target dna Dntps(all 4 varuety) Dna polymerase(thermostable) Pair of primer(20-30nucleotide) Magnesium Buffer ```

Question 45

Cycle of pcr

Answer 45

1) Denaturation-94degree celsius for 10 minutes 2) annealing:45 degree celsius for 4 minutes 3) elongation:72 degr celcaius variable time depenfing on the length

Question 46

Application of pcr

Answer 46

In medicine- detection of bacteria and virus Early detection of cancer Monitor cancer chemotherapy In forensic and legal medicine-parentage dispute Criminal case Evolutional study

Question 47

Real time pcr(qpcr)

Answer 47

``` Quantitative pcr Types of real timed reporters 1) SYBR green 2)Taq Mann 3)Molecular Beacons ```