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Question 1

What is the main role of RNA in cells?

Answer 1

RNA acts as the intermediate between DNA and protein synthesis, transferring genetic information from the nucleus to the ribosomes for translation

Question 2

What are the main structural components of RNA?

Answer 2

RNA consists of a ribose sugar, phosphate group, and four nitrogenous bases (adenine, guanine, cytosine, and uracil).

Question 3

How does RNA differ from DNA?

Answer 3

RNA contains the sugar ribose (instead of deoxyribose in DNA), is single-stranded, and uses uracil instead of thymine.

Question 4

What are the three main types of RNA and their functions?

Answer 4

1. mRNA
2. tRNA
3. rRNA

Question 5

What is mRNA and its role?

Answer 5

messenger RNA
- Carries the genetic information from DNA to the ribosome

Question 6

What is tRNA and its role?

Answer 6

transfer RNA
- Brings amino acids to the ribosome for protein synthesis

Question 7

What is rRNA and its role?

Answer 7

ribosomal RNA
- Forms the core of ribosomes and catalyzes protein synthesis

Question 8

What is transcription?

Answer 8

Transcription is the process by which RNA is synthesized from a DNA template

Question 9

What enzyme is responsible for synthesizing RNA during transcription?

Answer 9

RNA polymerase

Question 10

What are the three main stages of transcription?

Answer 10

1. Initiation
2. Elongation
3. Termination

Question 11

What happens during the initiation phase of transcription?

Answer 11

RNA polymerase binds to the promoter region of the DNA and begins unwinding the DNA to start RNA synthesis

Question 12

How does RNA polymerase know where to start transcription?

Answer 12

RNA polymerase recognizes and binds to specific sequences called promoters in the DNA

Question 13

What is the direction of RNA synthesis?

Answer 13

RNA is synthesized in the 5’ to 3’ direction

Question 14

What does the diagram showing RNA polymerase moving along the DNA strand represent?

Answer 14

It represents the elongation phase of transcription, where RNA polymerase moves along the template strand and adds complementary RNA nucleotides

Question 15

What are the two strands of DNA called in relation to transcription?

Answer 15

• The template strand
• The coding strand

Question 16

Which of the 2 strands of DNA (of transcription) is transcribed

Answer 16

Template Strand

Question 17

Which of the 2 strands of DNA (of transcription) is not transcribed

Answer 17

Coding Strand

Question 18

How is transcription terminated?

Answer 18

Transcription is terminated when RNA polymerase reaches a terminator sequence in the DNA, signaling the end of RNA synthesis.

Question 19

What is translation?

Answer 19

Translation is the process of synthesizing proteins from mRNA in the ribosome

Question 20

What is the genetic code?

Answer 20

The genetic code is a set of rules by which the nucleotide sequence in mRNA is translated into the amino acid sequence of a protein

Question 21

What are codons?

Answer 21

Codons are sequences of three nucleotides in mRNA that correspond to specific amino acids or stop signals during protein synthesis

Question 22

What is the start codon and its role?

Answer 22

The start codon is AUG, which signals the beginning of translation and codes for the amino acid methionine

Question 23

What is a stop codon, and how does it function?

Answer 23

Stop codons (UAA, UAG, UGA) signal the end of translation, causing the ribosome to release the completed polypeptide

Question 24

What are the three main components involved in translation?

Answer 24

1. mRNA
2. tRNA
3. Ribosomes

Question 25

What is the role of tRNA in translation?

Answer 25

tRNA brings the correct amino acid to the ribosome by matching its anticodon to the mRNA codon

Question 26

What are the two subunits of a ribosome?

Answer 26

The large subunit and the small subunit

Question 27

How do the subunits of the ribosome function during translation?

Answer 27

The small subunit binds the mRNA, and the large subunit catalyzes the formation of peptide bonds between amino acids

Question 28

What are the three main stages of translation?

Answer 28

1. Initiation
2. Elongation
3. Termination

Question 29

During which stage is the polypeptide chain extended?

Answer 29

Elongation

Question 30

How is the correct amino acid added to the polypeptide chain?

Answer 30

The anticodon of the tRNA pairs with the complementary codon in the mRNA, ensuring the correct amino acid is added

Question 31

How is translation terminated?

Answer 31

Translation is terminated when a stop codon is encountered, signaling the release of the newly formed polypeptide

Question 32

How do the diagrams help explain the translation process?

Answer 32

The diagrams show the interaction between mRNA, tRNA, and the ribosome, visualizing how codons are translated into amino acids and how the growing polypeptide chain is formed

Question 33

What is a promoter in the context of transcription?

Answer 33

A promoter is a specific DNA sequence where RNA polymerase binds to initiate transcription

Question 34

What are the three main steps of RNA processing in eukaryotes?

Answer 34

1. Capping
2. Polyadenylation
3. Splicing

Question 35

What is the role of splicing in mRNA processing?

Answer 35

Splicing removes introns (non-coding regions) from pre-mRNA and joins exons (coding regions) together to form the mature mRNA

Question 36

What does the “transcription bubble” in the diagram represent?

Answer 36

The transcription bubble is the region where the DNA double helix is unwound so RNA polymerase can synthesize RNA

Question 37

What signals the termination of transcription in prokaryotes?

Answer 37

A terminator sequence in the DNA signals RNA polymerase to stop transcription

Question 38

What is tRNA “charging”?

Answer 38

tRNA charging is the process of attaching an amino acid to its corresponding tRNA by an enzyme called aminoacyl-tRNA synthetase.

Question 39

What is the importance of the codon-anticodon interaction?

Answer 39

The anticodon of tRNA pairs with the codon of mRNA, ensuring that the correct amino acid is incorporated into the growing polypeptide chain

Question 40

What role does GTP play in the translation process?

Answer 40

GTP provides energy for various steps in translation, including ribosome assembly and translocation of tRNAs during elongation

Question 41

What is a polyribosome?

Answer 41

A polyribosome (or polysome) is a complex of multiple ribosomes translating the same mRNA simultaneously

Question 42

How does the diagram showing the ribosome moving along mRNA help explain translation?

Answer 42

It visualizes how ribosomes travel along mRNA, synthesizing proteins by adding amino acids as each codon is read