Chapter 12: Tools and Techniques — Online MCQ Test
BIOTECHNOLOGY · Grade 11 · CBSE(NCERT)
Practice Chapter 12: Tools and Techniques with a free chapter-wise online MCQ test.
This chapter covers: Microscopy chromatography centrifugation electrophoresis PCR polymerase chain reaction laboratory techniques biotechnology tools DNA analysis molecular diagnostics.
AI-generated questions from basic to board-exam level, with instant results and explanations.
Chapter 12: Tools and Techniques — Important Questions & Answers
Which instrument is commonly used to observe very small biological samples by passing light through them?
- A. Microscope
- B. Centrifuge
- C. Chromatograph
- D. Spectrophotometer
Answer: A. Microscope
A microscope is used to magnify and view tiny objects such as cells and tissues. It is a fundamental tool in biotechnology laboratories.
A microscope is used to magnify and view tiny objects such as cells and tissues. It is a fundamental tool in biotechnology laboratories.
In PCR, the enzyme that synthesizes new DNA strands is called:
- A. DNA ligase
- B. Taq polymerase
- C. Restriction endonuclease
- D. RNA polymerase
Answer: B. Taq polymerase
Taq polymerase is a heat-stable DNA polymerase used in PCR to extend primers and synthesize DNA. It is isolated from Thermus aquaticus.
Taq polymerase is a heat-stable DNA polymerase used in PCR to extend primers and synthesize DNA. It is isolated from Thermus aquaticus.
Why is centrifugation used in biotechnology laboratories?
- A. To increase the size of cells
- B. To separate components based on density
- C. To amplify DNA
- D. To stain chromosomes
Answer: B. To separate components based on density
Centrifugation separates particles according to their density by spinning the sample at high speed. Heavier particles move outward and settle faster.
Centrifugation separates particles according to their density by spinning the sample at high speed. Heavier particles move outward and settle faster.
A DNA sample contains fragments of different lengths. After electrophoresis, which fragment is expected to move the farthest from the well?
- A. The largest fragment
- B. The fragment with the highest mass only
- C. The smallest fragment
- D. All fragments move equally far
Answer: C. The smallest fragment
Smaller DNA fragments face less resistance in the gel and migrate faster. Therefore, they move farther than larger fragments.
Smaller DNA fragments face less resistance in the gel and migrate faster. Therefore, they move farther than larger fragments.
A band on an electrophoresis gel remains very close to the well. Which is the most likely reason?
- A. The fragment is very small
- B. The fragment is very large
- C. The DNA has no charge
- D. The gel contains no pores
Answer: B. The fragment is very large
Large DNA fragments move slowly through the gel and therefore stay closer to the well. Smaller fragments travel farther under the same conditions.
Large DNA fragments move slowly through the gel and therefore stay closer to the well. Smaller fragments travel farther under the same conditions.