Selected MCQ

Current Question
Monoclonal antibodies differ from polyclonal antibodies in that monoclonals:
  • A. Are produced by multiple B cell clones
  • B. Recognize multiple epitopes on the same antigen
  • C. Are derived from a single B cell clone and recognize a single epitope
  • D. Are less specific than polyclonals
Correct Answer: C
Explanation:
Monoclonal antibodies come from one B-cell clone, so they are identical and recognize one epitope. Polyclonal antibodies are produced by many B cells and recognize multiple epitopes on the antigen.
Related Question 1
The technique for producing monoclonal antibodies involves fusing a specific antibody-producing B cell with a myeloma cell (a cancer cell). This hybrid cell line is called a:
  • A. Bacteriophage
  • B. Hybridoma
  • C. Plasmid
  • D. Complement
Correct Answer: B
Explanation:
A hybridoma results from fusing a single B lymphocyte (which produces one antibody) with a myeloma cell, creating an immortal cell line that produces identical (monoclonal) antibodies.
Related Question 2
In flow cytometry, cells are labeled with fluorescent antibodies and passed in a stream through a laser. This technique primarily measures:
  • A. Cell size and internal complexity
  • B. DNA sequence variants
  • C. Protein structure by X-ray diffraction
  • D. Glycolytic activity
Correct Answer: A
Explanation:
Flow cytometry measures light scattering (size and granularity) and fluorescence from labeled markers, allowing rapid analysis of cell populations (size, complexity, marker expression).
Related Question 3
Histone H1 differs from the core histones (H2A, H2B, H3, H4) because it primarily functions to:
  • A. Form the core nucleosome octamer
  • B. Bind linker DNA between nucleosomes
  • C. Methylate DNA
  • D. Act as a transcription factor
Correct Answer: B
Explanation:
Histone H1 binds to the linker DNA between nucleosomes, helping to compact chromatin into higher-order structures.
Related Question 4
One major difference between intermediate filaments and microtubules is that intermediate filaments:
  • A. Contain α- and β-tubulin
  • B. Are polar structures
  • C. Degrade in the absence of ATP
  • D. Lack structural polarity
Correct Answer: D
Explanation:
Intermediate filaments are apolar (no distinct plus/minus ends) and do not require nucleotide hydrolysis for polymerization.