Question

question 25
gene expression refers to what process?
○ the process of transcribing dna into rna and translating rna into protein
○ the process of transcribing dna into rna and translating rna into chromatin
○ the process of transcribing rna into dna and translating dna into protein

question 26
if a strand of dna of sequence 5-aatagcgcggtattc-3 is replicated, which of the following accurately represents the newly synthesized dna strand?
○ 3-ccactgtgttacaag-5
○ 3-ttatcgcgccataag-5
○ 5-ttatcgcgccataag-3

Explanation:

Question 25

Gene expression involves two main steps: transcription (DNA to RNA) and translation (RNA to protein). The second option is incorrect as RNA is not translated into chromatin, and the third option has the transcription direction reversed (RNA to DNA is reverse transcription, not part of typical gene expression).

Step1: Recall DNA base pairing

In DNA replication, adenine (A) pairs with thymine (T), and cytosine (C) pairs with guanine (G). Also, the newly synthesized strand is antiparallel (opposite direction) to the template strand. The template strand is 5'-AATAGCGCGGTATTC-3', so the new strand will be 3' to 5' (antiparallel) with complementary bases.

Step2: Determine complementary bases

For each base in the template: A→T, T→A, G→C, C→G. Let's break down the template:
Template: 5'-A A T A G C G C G G T A T T C-3'
Complementary bases (new strand, 3' to 5'): T T A T C G C G C C A T A A G
So the new strand is 3'-TTATCGCGCCATAAG-5' (checking the options, this matches the second option). Also, check the direction: template is 5' to 3', new is 3' to 5', and bases are complementary.

Answer:

the process of transcribing DNA into RNA and translating RNA into protein

Question 26