Semester 1

Question 1

What are the components that make up the structure of DNA?

Answer 1

• phosphate backbone
• deoxyribose sugar
• nitrogenous base

Question 2

What is the significance of the antiparallel nature of DNA strands?

Answer 2

It is essential for DNA base pairing and the overall helical structure of DNA.

Question 3

Compare the structural differences between RNA and DNA.

Answer 3

-RNA contains ribose sugar
-RNA has uracil instead of thymine
-RNA is usually single stranded

Question 4

Why is DNA consider a better storage molecule compared to RNA?

Answer 4

It is more stable due to its double-stranded structure and the presence of deoxyribose, making it less susceptible to hydrolysis rather than RNA

Question 5

What are the 4 levels of protein structure?

Answer 5

Primary, secondary, tertiary and quaternary

Question 6

What is the primary structure?

Answer 6

The sequence of amino acids

Question 7

What is secondary structure?

Answer 7

The local folding patterns (eg, alpha helices and beta sheets)

Question 8

What is tertiary structure?

Answer 8

The overall 3D structure formed by the interactions among secondary structures.

Question 9

What is Quaternary structure?

Answer 9

The assembly of multiple polypeptide chains.

Question 10

Why might DNA, RNA and, proteins all be considered directional molecules?

Answer 10

They all have inherent polarity, with specific ends which are important for their functions.

Question 11

What is the function of messenger RNAs (mRNAs)?

Answer 11

Carries the genetic info from DNA to the ribosom, where it serves as a template for protein synthesis.

Question 12

What is the role of ribosomal RNA (rRNA) in the cell?

Answer 12

Non coding RNA that serves as a structural and catalytic component of the ribosome, facilitating the assembly of amino acids into proteins.

Question 13

What does the RNA world hypothesis propose?

Answer 13

Suggests that early life forms were based on self replicating RNA molecules that had both catalytic and genetic functions.

Question 14

Describe the structure and role of transfer RNA (tRNA)

Answer 14

Has a clover leaf structure with an anticodon loop that pairs with the mRNA codon and an acceptor stem that carries the corresponding amino acid.
Plays a crucial role in translating the mRNA sequence into protein.

Question 15

What are regulatory RNAs and what function do they serve?

Answer 15

Regulatory RNAs modulate gene expression by interfering with translation or leading to RNA degradation

Question 16

How does RNA interference work in regulating gene expression?

Answer 16

RNAi involves in processing double stranded RNA into short single stranded RNA pieces that guide the Argonaute protein to target mRNAs, leading to gene silencing.

Question 17

What is the mechanism of action for the siRNA drug Onpattro?

Answer 17

It inhibits the synthesis of the Transthyretin protein in the liver, effectively treating hereditary transthyretin amyloidosis

Question 18

What is the significance of using lipid nanoparticles in delivering RNA-based drugs?

Answer 18

Enhance the delivery of RNA drugs into cells improving stability and facilitation cellular uptake

Question 19

How do mRNA modifications contribute to vaccine efficacy?

Answer 19

They mimic endogenous mRNA, reducing inflammatory responses and increasing protein production which is crucial for the effectiveness of mRNA vaccines.