Pre AP Biology -GEN 6 Biotechnology- MCQ Exam Style Questions -New Syllabus

Pre AP Biology -GEN 6 Biotechnology- MCQ Exam Style Questions – New Syllabus 2025-2026

Pre AP Biology -GEN 6 Biotechnology- 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 these statements applies to plasmids?

a. They are pieces of $\text{RNA}$ taken up from the environment by prokaryotic cells.

b. They are small circular pieces of $\text{RNA}$ outside a cell’s chromosomes.

c. They are small circular pieces of non-chromosomal $\text{DNA}$.

d. They are pieces of $\text{DNA}$ taken up from the environment by prokaryotic cells.

▶️ Answer/Explanation

Detailed solution

Correct Option: c
Plasmids are extrachromosomal genetic elements found primarily in bacteria.
They consist of small, circular double-stranded $\text{DNA}$ molecules.
Unlike the main chromosome, they replicate independently within the cell.
They typically carry accessory genes, such as those for antibiotic resistance.
Options a and b are incorrect because plasmids are made of $\text{DNA}$, not $\text{RNA}$.
Option d is incorrect because it describes transformation rather than the definition of a plasmid itself.

Question

For which of these reasons is the Solexa/Illumina DNA sequencing method faster and less expensive than the Sanger method?

a. It sequences longer fragments of DNA.
b. It sequences more DNA fragments at the same time.
c. It does not require amplification of DNA fragments before sequencing.
d. It does not require the use of computer algorithms to find places where sequence fragments overlap.

▶️ Answer/Explanation

Correct Option: b

Detailed solution

The Illumina method utilizes massive parallel sequencing, allowing millions of fragments to be processed simultaneously.
In contrast, the Sanger method is relatively low-throughput, typically sequencing only one DNA fragment per reaction.
By sequencing many fragments at once, the time per base pair is significantly reduced.
This high-throughput capability drastically lowers the cost per gigabase (Gb) of data generated.
While Sanger reads are longer ($800-1000$ bp), Illumina’s speed comes from the sheer volume of short reads ($50-300$ bp).
Therefore, the ability to sequence more fragments at the same time is the primary reason for its efficiency.

Question

Suppose that you work in an institution that uses DNA technologies to distinguish between individuals who have sickle cell disease and those who have sickle cell trait or are sickle cell free. Which of these techniques would be the most applicable one in this situation?

a. cloning technique
b. transgenic technique
c. DNA fingerprinting technique
d. Southern blot technique

▶️ Answer/Explanation

Detailed solution

The correct option is d. Southern blot technique.
Sickle cell disease is caused by a point mutation in the $\beta$-globin gene.
This mutation often eliminates a specific restriction enzyme recognition site.

Southern blotting allows researchers to detect these Restriction Fragment Length Polymorphisms (RFLPs).
By comparing fragment sizes, one can distinguish between homozygous dominant, heterozygous (trait), and homozygous recessive (disease) genotypes.
Cloning and transgenic techniques are used for gene manipulation, not primary diagnosis.
DNA fingerprinting is typically used for forensics or paternity rather than specific single-gene mutations.

Pre AP Biology -GEN 6 Biotechnology- MCQ Exam Style Questions -New Syllabus