Week 10 - Molecular Genetics

Question 1

What discovery was highlighted in the 2024 Nobel Prize in Medicine?

A) DNA replication mechanisms
B) MicroRNA as a new level of regulating gene expression
C) CRISPR technology
D) Sanger sequencing advancements

Answer 1

Answer: B) MicroRNA as a new level of regulating gene expression

Question 2

What organism was studied in space to confirm vertebrate embryonic development?

A) Mice
B) Zebrafish
C) Fruit flies
D) C. elegans

Answer 2

Answer: B) Zebrafish

Question 3

What temperature is required to melt DNA strands during PCR?

A) 60°C
B) 72°C
C) 94°C
D) 37°C

Answer 3

Answer: C) 94°C

Question 4

During the PCR process, what happens during the annealing step?

A) DNA strands are separated
B) Primers bind to the target DNA
C) DNA polymerase is activated
D) Nucleotides are added

Answer 4

Answer: B) Primers bind to the target DNA

Question 5

What is the role of Taq polymerase in PCR?

A) It melts the DNA strands
B) It anneals the primers
C) It extends the DNA strands
D) It cuts the DNA

Answer 5

Answer: C) It extends the DNA strands

Question 6

What is Sanger sequencing primarily used for?

A) Amplifying DNA
B) Measuring the length of DNA strands to determine sequences
C) Cloning genes
D) Transcribing RNA

Answer 6

Answer: B) Measuring the length of DNA strands to determine sequences

Question 7

Which component is missing in dideoxynucleotides (ddNTPs) used in Sanger sequencing?

A) 2’ hydroxyl group
B) Phosphate group
C) Nitrogenous base
D) Sugar backbone

Answer 7

Answer: A) 2’ hydroxyl group

Question 8

What stops the replication process during Sanger sequencing?

A) The absence of a promoter
B) Incorporation of dideoxynucleotides
C) The addition of excess primers
D) High temperature

Answer 8

Answer: B) Incorporation of dideoxynucleotides

Question 9

What is a key difference between PCR and Sanger sequencing?

A) PCR amplifies DNA; Sanger sequencing does not
B) Sanger sequencing amplifies DNA; PCR does not
C) PCR requires more primers than Sanger sequencing
D) Sanger sequencing is faster than PCR

Answer 9

Answer: A) PCR amplifies DNA; Sanger sequencing does not

Question 10

What is the primary model organism for molecular cloning?

A) Yeast
B) Mice
C) E. coli
D) Zebrafish

Answer 10

Answer: C) E. coli

Question 11

Which plasmid is known for its ability to handle large DNA inserts?

A) pUC19
B) BAC (Bacterial Artificial Chromosome)
C) YAC (Yeast Artificial Chromosome)
D) Ti-plasmid

Answer 11

Answer: B) BAC (Bacterial Artificial Chromosome)

Question 12

What is the function of Agrobacterium tumefaciens in genetic engineering?

A) To cut DNA
B) To transform animal cells
C) To transfer recombinant DNA into plant cells
D) To replicate plasmids

Answer 12

Answer: C) To transfer recombinant DNA into plant cells

Question 13

What is the purpose of a selectable marker in recombinant DNA technology?

A) To enhance transcription
B) To indicate successful transformation
C) To cut DNA
D) To amplify genes

Answer 13

Answer: B) To indicate successful transformation

Question 14

What does the term “heterologous expression” refer to?

A) Expression of foreign genes in the same species
B) Expression of genes in a different organism
C) Expression of multiple genes simultaneously
D) Expression of non-coding RNA

Answer 14

Answer: B) Expression of genes in a different organism

Question 15

What are somatic cell nuclear transfer (SCNT) techniques used for?

A) To create transgenic plants
B) To clone animals
C) To amplify DNA
D) To sequence genes

Answer 15

Answer: B) To clone animals

Question 16

What is the main challenge in cloning animals compared to plants?

A) Animals lack totipotent cells
B) Plants have fewer genes
C) Animals do not have plasmids
D) Plants cannot reproduce asexually

Answer 16

Answer: A) Animals lack totipotent cells

Question 17

What was the first cloned mammal, and in what year was it successfully cloned?

A) Cow, 1996
B) Goat, 1997
C) Sheep, 1996
D) Pig, 1995

Answer 17

Answer: C) Sheep, 1996

Question 18

What does CRISPR-Cas9 technology allow for?

A) Amplifying genes
B) Editing genes at specific locations
C) Cloning organisms
D) Sequencing DNA

Answer 18

Answer: B) Editing genes at specific locations

Question 19

What is the function of microRNAs in gene regulation?

A) To enhance transcription
B) To inhibit translation of target mRNAs
C) To splice RNA
D) To replicate DNA

Answer 19

Answer: B) To inhibit translation of target mRNAs

Question 20

What is a major advantage of using yeast as a host organism for molecular cloning?

A) It replicates faster than bacteria
B) It can process complex proteins
C) It has a simpler genome
D) It is less expensive

Answer 20

Answer: B) It can process complex proteins

Question 21

What is the primary function of the Ti-plasmid in plants?

A) To enhance photosynthesis
B) To induce tumors
C) To store genetic information
D) To promote flowering

Answer 21

Answer: B) To induce tumors

Question 22

What is the significance of the Lin-14 gene in C. elegans?

A) It enhances transcription
B) It inhibits translation of specific mRNAs
C) It regulates cell division
D) It promotes growth

Answer 22

Answer: B) It inhibits translation of specific mRNAs

Question 23

Which type of RNA is involved in the regulation of gene expression through microRNA pathways?

A) mRNA
B) tRNA
C) rRNA
D) Non-coding RNA

Answer 23

Answer: D) Non-coding RNA

Question 24

in vivo vs. in vitro?

Answer 24

1. In vivo = in real life - keep everything at a cell life
2. In vitro = glass/no life - isolated systems, almost chemistry

Question 25

what are dNTPs?

Answer 25

dNTP = nucleotide monomers, dATP, dTTP, dCTP, dGTP

Question 26

What’s the difference between DDNTP, DNTP and NTP?

Answer 26

No OH groups = DDNTP
1 OH group = DNTP
2 OH group = NTP

Question 27

How does Sanger sequencing work?

Answer 27

1. The diphosphate group breaks off and the energy is used to a new covalent bond to make a sugar-phosphate backbone
2. The 3’ prime end on the sugar-phosphate backbone on the DNTP or NTP allows for continuous polymerisation
3. Then a di-deoxynucleotide triphosphate without the 2’ or 3’ prime HO group, cannot continue to polymerize, but it can join the chain with its triphosphate group
4. Chain stops

Question 28

What’s the main nucleotide that the processes don’t share?

Answer 28

DDTNPs are only used in Sanger sequencing, PCR does not

Question 29

What’s the Maximum number of cycles in Sanger sequencing?

Answer 29

5

Question 30

How many primers are used in PCR and SS?

Answer 30

1. PCR = 2 (for 2-stranded DNA)
2. SS = 1

Question 31

What would happen if SS used 2 primers?

Answer 31

It would work but it would be confusing, doing 2x work and overlapping sequences that don’t match up, look like heterozygosity at every DNTP
DNA is not identical on the two strands but reverse complementary - so the 2 sequences will not be identical but anti-parallel - eg. no correlation between the 2 sequences with 2 primers