Pre AP Biology -GEN 3.2 RNA Transcription- MCQ Exam Style Questions -New Syllabus

Pre AP Biology -GEN 3.2 RNA Transcription- MCQ Exam Style Questions – New Syllabus 2025-2026

Pre AP Biology -GEN 3.2 RNA Transcription- MCQ Exam Style Questions – Pre AP Biology – per latest Pre AP Biology Syllabus.

Pre AP Biology – MCQ Exam Style Questions- All Topics

Question

Which of the following characteristics distinguishes plant viruses from animal viruses?

a. Plant viruses are easily curable.

b. Plant viruses are covered by a membrane envelope.

c. Plant viruses lack the ability to actively infect a host cell.

d. Plant viruses lack the ability to replicate their RNA genome.

▶️ Answer/Explanation

Detailed solution

The correct option is c.

Plant cells possess a rigid cellulose cell wall that acts as a physical barrier.
Unlike animal viruses, plant viruses cannot actively penetrate this wall via endocytosis.
They typically require mechanical damage or insect vectors to enter the cell.
Once inside, they move between cells through channels called plasmodesmata.
Animal viruses, by contrast, often bind to receptors to trigger active entry.
Options a, b, and d are incorrect as they do not represent defining distinctions.

Question

Which of these characteristics applies to pseudogenes and NOT to genes?

a. They are not transcribed.

b. They contain longer ORFs.

c. They do not have introns.

d. They use a different genetic code.

▶️ Answer/Explanation

Detailed solution

The correct option is c. They do not have introns.
Pseudogenes are non-functional segments of DNA that resemble functional genes.
Processed pseudogenes are formed via reverse transcription of $mRNA$.
Because they originate from $mRNA$, the introns have already been spliced out.
Functional eukaryotic genes typically contain both exons and introns.
Therefore, the absence of introns is a defining trait of processed pseudogenes.
Other options like (a) are incorrect as some pseudogenes are still transcribed.
Option (b) is incorrect because pseudogenes usually have shorter or broken $ORFs$.

Question

Which of these statements describes the initiation of transcription?

a. RNA polymerase II binds the TATA box.

b. A coactivator called a mediator forms a bridge between the promoter and the gene to be transcribed.

c. Transcription factors bind the promoter, followed by RNA polymerase.

d. Enhancer regions bind to promoter regions.

▶️ Answer/Explanation

Detailed solution

The correct option is c.
Transcription initiation in eukaryotes begins when transcription factors recognize and bind to the promoter region.
Specific proteins like $TFIID$ bind to the $TATA$ box to recruit other factors.
Once the transcription factor complex is assembled, RNA polymerase is recruited to the site.
RNA polymerase II cannot typically bind to the $DNA$ template directly or efficiently on its own.
This sequential assembly forms the transcription initiation complex required to start $mRNA$ synthesis.

Pre AP Biology -GEN 3.2 RNA Transcription- MCQ Exam Style Questions -New Syllabus