Central Dogma in Molecular Biology

Question 1

producing 2 identical copies of the original DNA.

Answer 1

DNA replication

Question 2

DNA replication occurs during what phase of the cell cycle before cell division.

Answer 2

S phase

Question 3

must be accurately copied to ensure each daughter cells receives exact genetic information as of the parent cell.

Answer 3

DNA

Question 4

synthesized a primer that will start the replication.

Answer 4

Primase

Question 5

a short sequence of RNA with a 3’ end than can be elongated by DNA polymerase.

Answer 5

Primer

Question 6

add new nucleotides to growing strand

Answer 6

DNA polymerase III

Question 7

removes primer (since it is RNA) and replace by DNA

Answer 7

DNA polymerase I-

Question 8

DNA pol III elongates the primer by adding new bases, growing the strand in a 5’ to 3’ direction

Answer 8

Leading strand-

Question 9

DNA pol III adds nucleotides (backward direction) from the replication fork producing short segment called Okazaki fragments.

Answer 9

Lagging strand-

Question 10

Lagging strand- replication fork producing short segment called

Answer 10

Okazaki fragments.

Question 11

joins together or sealed the okazaki fragments by addition of phosphate group.

Answer 11

DNA Ligase-

Question 12

Types of DNA repair mechanism

Answer 12

Base excision repair (BER)
Nucleotide excision repair (NER)
Mismatch repair (MMR)
Double strand break repair
Homology directed repair

Question 13

It Repairs single base that undergone alkylation, deamination of oxidation.

Answer 13

Base excision repair

Question 14

Various enzyme (glycosylase, endonuclease, polymerase and ligase) remove mutated base from the double helix (excision) and replaced it with a normal.

Answer 14

Base excision repair

Question 15

These chemical process if not corrected can lead incorrect base pairing resulting in substitution or deletion of bases.

Answer 15

Base excision repair

Question 16

Detects and repair distortion (bulky) to the DNA strand as result of environment such a sun UV light ad some chemotherapeutic drugs.

Answer 16

Nucleotide excision repair (NER)

Question 16

DNA glycosylase detects damaged bases.

Answer 16

Base excision repair

Question 17

causes bulky DNA adducts.

Answer 17

Thymine dimerization

Question 18

Wide strand that contain the lesion is excise (remove) and DNA polymerase enzyme synthesized the new strand

Answer 18

Nucleotide excision repair (NER)

Question 19

Repair spontaneous base–base mis pairs and small insertions–deletion loops generated during DNA replication or recombination

Answer 19

DNA mismatch repair (MMR)

Question 20

recognizes the mismatch to be followed by recruitment of repair enzymes that excise incorrect sequence.

Answer 20

DNA mismatch repair (MMR)

Question 21

DNA polymerase and ligase resynthesized new strand using the parental strand.

Answer 21

DNA mismatch repair (MMR)

Question 22

Repair double stranded breaks (DSB)

Answer 22

Homologous recombination repair (HR)

Question 23

The repair mechanism is active during S ang G2 phase.
Involves unwinding of the damaged DNA helix and invasion of the damaged strands into a homologous DNA duplex molecule.

Answer 23

Homologous recombination repair (HR)

Question 24

The sister chromatid or homologous chromosome is used as template for synthesizing new strand.

Answer 24

Homologous recombination repair (HR)

Question 25

Also repair double strand breaks (DSB) It is active throughout the cell cycle. Error prone. Repair mechanism does not need homologous template

Answer 25

Non homologous end joining repair (NHEJ)

Question 26

changes in the base sequence of DNA resulting to genetic variation among organisms, in the case of human it causes disease mostly are malignant condition.

Answer 26

Mutation

Question 27

are cause by environment like radiation, UV light, carcinogens and internal factors such as spontaneous mutation.

Answer 27

Mutation

Question 28

Extreme exposure to environment increases the rate of

Answer 28

Mutation

Question 29

The process of transferring the genetic information from DNA to RNA.

Answer 29

Transcription

Question 30

A particular gene is transcribed in response to the need of the cell.

Answer 30

Transcription

Question 31

catalyzes by reverse transcriptase enzyme producing complimentary DNA (cDNA) from mRNA.

Answer 31

Reverse transcription-

Question 32

located upstream contains TATA box, recognition site for transcription.

Answer 32

Promoter region

Question 33

located downstream. Forms a hairpin-like strand signaling the end of transcription.

Answer 33

Termination region

Question 34

structure of a gene is consist of a

Answer 34

Promoter region RNA-coding region Termination region

Question 35

these are proteins that regulates transcription process (when to turn on and how much).

Answer 35

Transcription factors-

Question 36

is a mark where RNA polymerase bind and start copying the DNA strand. In eukaryotes it is known as TATA box.

Answer 36

Promoter

Question 37

The RNA polymerase unwinds the DNA exposing 10-20 bases at a time forming the transcription bubble. One strand is only needed for the transcription (template strand).

Answer 37

Elongation

Question 38

Elongation in what direction

Answer 38

5' - 3'

Question 39

The RNA pol stops moving on the DNA template after reaching the termination region.

Answer 39

Termination

Question 40

The transcribed RNA is a single stranded complementary copy of one of 2 strands

Answer 40

Elongation

Question 41

Transcription stops, transcribed RNA is release from the template strand.

Answer 41

Termination

Question 42

RNA modifications (maturation of RNA) process occurs in ?

Answer 42

Nucleus

Question 43

removal of introns(non-coding protein) and rejoining of exons (protein-coding gene). This process is catalyzed by

Answer 43

Splicing spliceosome.

Question 44

A process of decoding biologic information from mRNA to synthesize a protein.

Answer 44

Translation

Question 45

Translation occur in the?

Answer 45

Ribosome

Question 46

Enzymatic process of amino acid side chain modification after their protein biosynthesis.

Answer 46

Post Translation modification

Question 47

It result to protein diversity.

Answer 47

Post Translation modification

Question 48

A molecular laboratory technique used in clinical diagnostics.

Answer 48

Polymerase chain reaction

Question 49

An in-vitro amplification/replication of DNA/RNA fragments through a cycle of heating and cooling.

Answer 49

Polymerase chain reaction

Question 50

Generates millions of copies of DNA after the process. Invented by MULLIS in 1983.

Answer 50

Polymerase chain reaction

Question 51

Components of PCR

Answer 51

DNA template/fragment- from the sample Primer (synthetic) Taq DNA Polymerase Synthetic deoxynucleotide triphosphate- dNTPs Buffer

Question 52

These are fragments of interest or the target DNA for amplification, serves as a template.

Answer 52

DNA fragments

Question 53

are present in biological samples. They are need to be purified and isolated from the sample before the actual PCR.

Answer 53

DNA fragments

Question 54

Single stranded DNA (10-30 nucleotides) synthesized chemically(synthetic primer).

Answer 54

PRIMERS

Question 55

Serves as the starting point for the amplification.

Answer 55

PRIMERS

Question 56

Adds dNTPs to the growing strand of DNA.

Answer 56

Taq DNA Polymerase

Question 57

Extracted from Thermus aquaticus a bacteria that lives in hot springs a can withstand hot temperature (> 100 C).

Answer 57

Taq DNA Polymerase

Question 58

Provide nucleotides during DNA amplification.

Answer 58

dNTP- Deoxynucleotide triphosphate

Question 59

Polymerase chain reaction process

Answer 59

Denaturation Annealing Extension

Question 60

At 94 C the double-stranded DNA melts and opens into two pieces of single-stranded DNA

Answer 60

Denaturation

Question 61

At 54 C the primers pair up (anneal) with the single-stranded template.

Answer 61

Annealing

Question 62

at 72 C DNA polymerase extends the primer by its polymerase activity by adding dNTPS.

Answer 62

Extension

Question 63

Polymerase chain reaction process cycle repeat for?

Answer 63

25-40 times to make a million copies of DNA sequence.

Question 64

A technique used for identification and quantification of RNA.

Answer 64

RT-PCR

Question 65

is used to allow a single strand of RNA to be transcribe into a complementary strand of DNA (cDNA).

Answer 65

reverse transcriptase enzyme

Question 66

used to detect and study many RNA viruses.

Answer 66

RT-PCR