Central Dogma EOC

What is the role of mRNA in translation?

• To degrade proteins

• To carry genetic information from DNA to ribosomes

• To synthesize DNA

• To transport amino acids

Answer explanation

mRNA plays a crucial role in translation by carrying genetic information from DNA to ribosomes, where proteins are synthesized. This process is essential for translating the genetic code into functional proteins.

What is the function of tRNA during translation?

• To match codons with amino acids

• To synthesize DNA

• To carry genetic information

• To degrade mRNA

Answer explanation

tRNA's primary function during translation is to match codons on the mRNA with the appropriate amino acids, facilitating the assembly of proteins. This is crucial for accurate protein synthesis.

What is the role of ribosomes in translation?

• To degrade proteins

• To build polypeptides

• To replicate DNA

• To transport mRNA

Answer explanation

Ribosomes are essential for translation as they facilitate the assembly of amino acids into polypeptides, forming proteins based on the sequence of mRNA. Thus, the correct role of ribosomes is to build polypeptides.

What is the difference between DNA and RNA?

• DNA is found in the cytosol

• DNA contains ribose sugar

• RNA is double-stranded

• RNA contains uracil instead of thymine

Answer explanation

RNA differs from DNA in that it contains uracil instead of thymine. DNA has deoxyribose sugar and is typically double-stranded, while RNA has ribose sugar and is usually single-stranded.

Where does transcription occur in eukaryotes?

• In the nucleus

• In the cytosol

• In the ribosome

• In the mitochondria

Answer explanation

Transcription in eukaryotes occurs in the nucleus, where DNA is transcribed into mRNA. This process is essential for gene expression, while the cytosol and ribosome are involved in translation, not transcription.

What is the function of RNA polymerase?

• To replicate DNA

• To transport amino acids

• To degrade mRNA

• To synthesize RNA from a DNA template

Answer explanation

RNA polymerase synthesizes RNA by using a DNA template, a crucial step in gene expression. The other options do not accurately describe its primary function.

What is splicing in RNA processing?

• The degradation of mRNA

• The removal of certain pieces of RNA

• The addition of a poly-A tail

• The synthesis of DNA

Answer explanation

Splicing in RNA processing refers to the removal of non-coding sequences (introns) from the pre-mRNA, allowing the coding sequences (exons) to be joined together. This process is essential for producing mature mRNA.

What is the non-coding strand of DNA?

• The strand that is degraded after transcription

• The template strand for RNA synthesis

• The strand that is not used in transcription

• The strand that binds to ribosomes

Answer explanation

The non-coding strand of DNA is the template strand for RNA synthesis, as it serves as the guide for RNA polymerase to create a complementary RNA strand during transcription.

What is the role of the ribosome in translation?

• To build polypeptides by reading mRNA

• To synthesize DNA

• To transport amino acids

• To degrade proteins

Answer explanation

The ribosome's primary role in translation is to build polypeptides by reading the sequence of mRNA. It facilitates the assembly of amino acids into a protein chain, making this choice the correct answer.

What is the function of the start codon?

• To replicate DNA

• To degrade mRNA

• To terminate transcription

• To signal the beginning of translation

Answer explanation

The start codon, typically AUG, signals the beginning of translation in protein synthesis. It is essential for ribosomes to recognize where to begin translating mRNA into a protein.