Biophysical Methods & Instrumentation – MCQs

1. Which of the following is a spectroscopic technique widely used in biophysics?
(A) X-ray crystallography
(B) NMR spectroscopy
(C) MRI
(D) All of the above

2. X-ray crystallography is primarily used to determine:
(A) DNA sequences
(B) Protein 3D structures
(C) Ion concentration in blood
(D) pH of a solution

3. NMR spectroscopy provides information about:
(A) Static 3D structures only
(B) Dynamic structure and molecular motions
(C) Only DNA melting point
(D) Only protein denaturation

4. Which technique is based on the scattering of light by molecules?
(A) UV spectroscopy
(B) Circular dichroism
(C) Dynamic light scattering (DLS)
(D) Mass spectrometry

5. Circular dichroism (CD) spectroscopy is mainly used to study:
(A) Protein secondary structure
(B) DNA sequencing
(C) Enzyme kinetics
(D) Carbohydrate metabolism

6. The Bragg’s law is fundamental to:
(A) NMR
(B) X-ray diffraction
(C) Fluorescence microscopy
(D) IR spectroscopy

7. Which of the following techniques uses magnetic fields and radio waves?
(A) NMR spectroscopy
(B) X-ray diffraction
(C) Atomic force microscopy
(D) Mass spectrometry

8. Atomic force microscopy (AFM) provides:
(A) Topographical images at nanoscale
(B) Protein sequences
(C) DNA base pair order
(D) Enzyme catalytic rates

9. Fluorescence Resonance Energy Transfer (FRET) is used to study:
(A) Long-range protein folding
(B) Molecular distances and interactions
(C) Heat denaturation
(D) Protein hydrolysis

10. Which technique is used to measure protein-ligand binding affinities in real time?
(A) Surface plasmon resonance (SPR)
(B) X-ray diffraction
(C) NMR spectroscopy
(D) SDS-PAGE

11. SDS-PAGE separates proteins based on:
(A) Charge only
(B) Size (molecular weight)
(C) DNA content
(D) Enzyme activity

12. Western blotting is used to:
(A) Visualize proteins after electrophoresis
(B) Sequence DNA
(C) Measure RNA content
(D) Study carbohydrate folding

13. Isothermal titration calorimetry (ITC) measures:
(A) Heat changes during binding
(B) Protein secondary structure
(C) X-ray scattering angles
(D) Magnetic resonance signals

14. Differential scanning calorimetry (DSC) is used to study:
(A) Thermal denaturation of biomolecules
(B) Protein electrophoresis
(C) DNA base sequencing
(D) Atomic interactions in crystals

15. UV-Vis spectroscopy is commonly used to measure:
(A) Protein and nucleic acid concentrations
(B) Membrane potentials
(C) Enzyme turnover numbers
(D) Ion channels

16. Fluorescence spectroscopy is especially sensitive to:
(A) Aromatic amino acids like tryptophan
(B) Carbohydrates only
(C) Sulfur bonds
(D) Metallic ions only

17. Electron microscopy uses:
(A) Electron beams for imaging
(B) Light waves
(C) Radio waves
(D) Magnetic resonance

18. Cryo-electron microscopy (Cryo-EM) is widely used for:
(A) Visualizing biomolecules at near-atomic resolution
(B) Measuring temperature
(C) Protein denaturation
(D) Measuring enzyme kinetics

19. Which method separates molecules based on density?
(A) Centrifugation
(B) Electrophoresis
(C) X-ray crystallography
(D) MRI

20. Analytical ultracentrifugation helps in studying:
(A) Molecular weight and shape of biomolecules
(B) Protein sequencing
(C) Atomic bonding
(D) Enzyme turnover

21. Flow cytometry is used for:
(A) Cell sorting and analysis
(B) Protein secondary structure
(C) X-ray crystallography
(D) NMR structure prediction

22. Which method separates DNA fragments by size?
(A) Gel electrophoresis
(B) Western blotting
(C) Mass spectrometry
(D) ITC

23. MALDI-TOF is a technique used in:
(A) Mass spectrometry
(B) Electrophoresis
(C) Microscopy
(D) Calorimetry

24. Fluorescent dyes such as DAPI are used to stain:
(A) DNA
(B) Proteins
(C) Lipids
(D) Carbohydrates

25. Which method provides atomic resolution structures of solids?
(A) Solid-state NMR
(B) UV spectroscopy
(C) AFM
(D) SDS-PAGE

26. Raman spectroscopy provides information about:
(A) Vibrational modes of molecules
(B) Protein size
(C) DNA length
(D) Atomic number

27. Two-dimensional gel electrophoresis separates proteins by:
(A) Isoelectric point and size
(B) Density and charge
(C) Atomic number
(D) Thermal stability

28. Chromatography separates molecules based on:
(A) Size, charge, or affinity
(B) Atomic weight only
(C) DNA sequence
(D) pH gradient

29. Affinity chromatography relies on:
(A) Specific binding interactions
(B) Random collisions
(C) Density gradients
(D) Magnetic fields

30. Gas chromatography is mostly used for:
(A) Small volatile molecules
(B) Proteins only
(C) DNA bases
(D) Polysaccharides

31. High-performance liquid chromatography (HPLC) is:
(A) A separation technique for biomolecules
(B) A type of microscopy
(C) Used for DNA replication
(D) A crystallization technique

32. Surface plasmon resonance works by detecting changes in:
(A) Refractive index at a sensor surface
(B) DNA base order
(C) X-ray scattering
(D) Protein electrophoresis

33. ELISA is a technique used for:
(A) Detecting specific proteins or antigens
(B) Protein folding
(C) Enzyme kinetics only
(D) X-ray diffraction

34. Atomic absorption spectroscopy is used to analyze:
(A) Metal ions in biological samples
(B) Protein folding
(C) DNA secondary structure
(D) Lipid membranes

35. Which method uses fluorescent probes to study cell structures?
(A) Confocal microscopy
(B) AFM
(C) X-ray diffraction
(D) Mass spectrometry

36. Single-molecule techniques include:
(A) Optical tweezers and patch-clamp
(B) SDS-PAGE
(C) ELISA
(D) ITC

37. Patch-clamp technique measures:
(A) Ionic currents through membranes
(B) Protein molecular weight
(C) DNA hybridization
(D) Cell size

38. Optical tweezers use:
(A) Laser beams to trap and manipulate particles
(B) Magnets for atomic resolution
(C) X-rays to image DNA
(D) IR light to measure proteins

39. Microscopy that surpasses the diffraction limit is:
(A) Super-resolution microscopy
(B) Confocal microscopy
(C) Bright-field microscopy
(D) Polarizing microscopy

40. Förster distance in FRET typically ranges around:
(A) 1–10 nm
(B) 100–500 nm
(C) 1–5 µm
41. Mass spectrometry measures:
(A) Mass-to-charge ratio of ions
(B) DNA sequence
(C) Protein folding rate
(D) Atomic bonding energy

42. Which imaging technique is used in living cells to track proteins?
(A) Fluorescence microscopy
(B) X-ray diffraction
(C) SDS-PAGE
(D) Centrifugation

43. Which instrument detects absorbance at 280 nm to quantify proteins?
(A) UV spectrophotometer
(B) IR spectrometer
(C) AFM
(D) Electron microscope

44. Nuclear Overhauser Effect (NOE) is studied using:
(A) NMR spectroscopy
(B) X-ray crystallography
(C) DSC
(D) Mass spectrometry

45. Scanning electron microscopy (SEM) provides:
(A) Surface images with high resolution
(B) Atomic 3D structure
(C) Protein folding kinetics
(D) DNA base order

46. Transmission electron microscopy (TEM) provides:
(A) Internal cellular structures at high resolution
(B) Protein secondary structure
(C) X-ray patterns
(D) DNA sequencing

47. The technique for separating biomolecules by electrical charge in a pH gradient is:
(A) Isoelectric focusing
(B) SDS-PAGE
(C) HPLC
(D) ITC

48. Atomic force microscopy can operate in:
(A) Air, liquid, or vacuum environments
(B) Only dry air
(C) Only cryogenic conditions
(D) Only aqueous buffers

49. Which spectroscopy is most suitable for studying protein folding in real time?
(A) Fluorescence spectroscopy
(B) Mass spectrometry
(C) Centrifugation
(D) Gas chromatography

50. Biophysical instrumentation is crucial for:
(A) Understanding structure, dynamics, and interactions of biomolecules
(B) Planetary movements
(C) Geological studies
(D) Weather forecasting only