1.2 RNA and protein synthesis

Question 1

What is the primary function of RNA in cells?

Answer 1

To serve as a template for protein synthesis.

Question 2

True or False: RNA is generally single-stranded.

Answer 2

True.

Question 3

Fill in the blank: The process of synthesizing RNA from DNA is called _______.

Answer 3

transcription.

Question 4

What are the three main types of RNA?

Answer 4

Messenger RNA (mRNA), Transfer RNA (tRNA), and Ribosomal RNA (rRNA).

Question 5

Which type of RNA carries the genetic code from DNA to the ribosome?

Answer 5

Messenger RNA (mRNA).

Question 6

What is the role of tRNA during protein synthesis?

Answer 6

To bring amino acids to the ribosome based on the codon sequence of mRNA.

Question 7

True or False: Ribosomal RNA (rRNA) is a component of ribosomes.

Answer 7

True.

Question 8

What are codons?

Answer 8

Sequences of three nucleotides on mRNA that specify a particular amino acid.

Question 9

What is the start codon for protein synthesis?

Answer 9

AUG.

Question 10

What is the end codon that signals termination of protein synthesis?

Answer 10

UAA, UAG, or UGA.

Question 11

What enzyme is responsible for synthesizing RNA during transcription?

Answer 11

RNA polymerase.

Question 12

True or False: DNA contains uracil instead of thymine.

Answer 12

False.

Question 13

Fill in the blank: The process of translating mRNA into a protein is called _______.

Answer 13

translation.

Question 14

Where does translation occur in the cell?

Answer 14

In the ribosome.

Question 15

Which molecule acts as the template for translation?

Answer 15

mRNA.

Question 16

What is the role of the ribosome in protein synthesis?

Answer 16

To facilitate the binding of tRNA to mRNA and catalyze the formation of peptide bonds.

Question 17

What is the function of the anticodon on tRNA?

Answer 17

To pair with the corresponding codon on mRNA.

Question 18

True or False: All proteins are made up of the same 20 amino acids.

Answer 18

True.

Question 19

What is a polypeptide?

Answer 19

A chain of amino acids linked by peptide bonds.

Question 20

What process involves the modification of RNA after transcription?

Answer 20

RNA processing.

Question 21

What are introns?

Answer 21

sections of DNA that don’t code for proteins

Question 22

What are exons?

Answer 22

sections of DNA that do code for proteins.

Question 23

What is the significance of the 5’ cap and poly-A tail in mRNA?

Answer 23

They protect mRNA from degradation and assist in translation.

Question 24

True or False: The genetic code is universal among all living organisms.

Answer 24

True.

Question 25

What is the role of aminoacyl-tRNA synthetase?

Answer 25

To attach the correct amino acid to its corresponding tRNA.

Question 26

What is meant by 'gene expression'?

Answer 26

The process by which information from a gene is used to synthesize a functional gene product, usually a protein.

Question 27

Fill in the blank: The sequence of nucleotides in DNA is transcribed into _______.

Answer 27

mRNA.

Question 28

What are the three stages of translation?

Answer 28

Initiation, elongation, and termination.

Question 29

True or False: Proteins can function as enzymes, structural components, and signaling molecules.

Answer 29

True.

Question 30

What is the role of the signal peptide in protein synthesis?

Answer 30

To direct the nascent protein to its proper location within the cell.

Question 31

What is the significance of post-translational modifications?

Answer 31

They alter the protein's function, activity, stability, and localization.

Question 32

What is the difference between prokaryotic and eukaryotic transcription?

Answer 32

Prokaryotic transcription occurs in the cytoplasm and lacks a nucleus, while eukaryotic transcription occurs in the nucleus and involves RNA processing.

Question 33

Fill in the blank: The genetic code is read in sets of three nucleotides called _______.

Answer 33

codons.

Question 34

What is the role of the promoter in transcription?

Answer 34

To initiate the transcription of a specific gene.

Question 35

What is a transcription factor?

Answer 35

A protein that regulates the transcription of specific genes by binding to nearby DNA.

Question 36

What does 'alternative splicing' refer to?

Answer 36

The process by which different combinations of exons are joined together to produce multiple protein variants from a single gene.

Question 37

True or False: Each tRNA molecule can carry multiple different amino acids.

Answer 37

False.

Question 38

What is the role of the small subunit of the ribosome?

Answer 38

To bind mRNA and initiate translation.

Question 39

What is the role of the large subunit of the ribosome?

Answer 39

To catalyze the formation of peptide bonds between amino acids.

Question 40

Fill in the blank: The _______ site of the ribosome holds the tRNA carrying the growing polypeptide chain.

Answer 40

P (peptidyl) site.

Question 41

What happens during the elongation phase of translation?

Answer 41

Amino acids are added one by one to the growing polypeptide chain.

Question 42

What is the role of the release factor in translation?

Answer 42

To terminate translation by recognizing the stop codon and promoting the release of the polypeptide.

Question 43

True or False: The sequence of amino acids ultimately determines the three-dimensional structure of a protein.

Answer 43

True.

Question 44

What is the central dogma of molecular biology?

Answer 44

DNA -> RNA -> Protein.

Question 45

What is a mutation?

Answer 45

A change in the DNA sequence that can affect protein synthesis.

Question 46

Fill in the blank: The three-dimensional shape of a protein is crucial for its _______.

Answer 46

function.

Question 47

how many amino acids

Answer 47

20

Question 48

What is the primary function of microRNA?

Answer 48

MicroRNA regulates gene expression by binding to target mRNA, leading to its degradation or inhibition of translation.

Question 49

True or False: tRNA is responsible for carrying amino acids to the ribosome during protein synthesis.

Answer 49

True

Question 50

Fill in the blank: rRNA is a component of the ________ and plays a crucial role in protein synthesis.

Answer 50

ribosome

Question 51

What process involves the synthesis of RNA from a DNA template?

Answer 51

Transcription

Question 52

Multiple Choice: Which of the following describes translation? A) DNA replication B) RNA synthesis C) Protein synthesis D) mRNA processing

Answer 52

C) Protein synthesis

Question 53

what is translation?

Answer 53

The process where a cell reads mRNA to build proteins.

Question 54

what is transcription?

Answer 54

the process of making an RNA copy of a gene's DNA sequence.

Question 55

What is the process of translation

Answer 55

Initiation - Use of start codon being AUG Chain elongation - The building of the amino acid sequence from the codons. Termination - The completion of the mRNA sequence with a stop codon: UAG, UAA or UGA

Question 56

what does a gene consist of?

Answer 56

a unique sequence of nucleotides that code for a functional protein or an RNA molecule.

Question 57

Why are both exons and introns transcribed, but only exons are translated?

Answer 57

Introns are removed during RNA processing, leaving only exons to make a polypeptide.

Question 58

where does transcription occur?

Answer 58

the nucleus

Question 59

what's the roles of DNA, mRNA, tRNA, and rRNA in transcription and translation.

Answer 59

DNA: Contains the genetic code for proteins (template for mRNA). mRNA: Carries the genetic code from DNA to the ribosome (template for protein synthesis). tRNA: Brings amino acids to the ribosome, matching them to the mRNA codons. rRNA: Makes up the ribosome, where proteins are assembled.

Question 60

what's the relationship between DNA codons, RNA codons, anticodons and amino acids

Answer 60

DNA Codons: Code for amino acids. RNA Codons: mRNA version of DNA codons, used to make proteins. Anticodons: tRNA matches with RNA codons. Amino Acids: Build proteins, based on RNA codons. DNA → RNA → tRNA → Amino Acids!

Question 61

what's the difference between coding (gene) and template strands of DNA

Answer 61

Coding Strand: Has the same sequence as mRNA. Template Strand: Used to make mRNA. The template is copied to create the mRNA, and the coding strand matches the mRNA.

Question 62

what is miRNA?

Answer 62

- micro RNA - small non coding RNA molecules (22 nucleotides) - Important in regulating gene expansion

Question 63

what is the role of rRNA?

Answer 63

to synthesise proteins using mRNA as a guide.

Question 64

what is the role of tRNA

Answer 64

transport of amino acids to ribosome