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Updated: Jun 19, 2026
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Quantitative Optical Microscopy: Measurement of Cellular Biophysical Features with a Standard Optical Microscope
Published on: April 7, 2014
THE REFRACTIVE INDICES OF WHOLE CELLS.
1Laboratory of General Physiology, Harvard University, Cambridge.
The Journal of General Physiology
|October 30, 2009
Summary
Researchers measured the refractive indices of Phycomyces sporangiophores, finding effective values between 1.35 and 1.40. This study provides new insights into the optical properties of these plant cells.
Area of Science:
- Plant biology
- Biophysics
- Optical properties of cells
Background:
- Understanding the optical properties of plant cells is crucial for various biological and biophysical studies.
- Previous measurements of plant cell refractive indices have yielded a range of values, necessitating further investigation.
Purpose of the Study:
- To compute the refractive indices of intact sporangiophores of Phycomyces.
- To compare these findings with existing data on plant cell refractive indices.
Main Methods:
- Measurements of focal length and radius of curvature were performed on intact sporangiophores.
- Effective refractive indices (n) were calculated based on these geometric parameters.
Main Results:
- Effective refractive indices for six Phycomyces cells ranged from 1.35 to 1.40.
- The average effective refractive index was determined to be 1.38.
- A discrepancy was noted when compared to higher values reported by Senn for other plant cells (n = 1.37 to 1.52).
Conclusions:
- The study presents a precise method for determining the refractive index of intact sporangiophores.
- The observed lower refractive index values for Phycomyces sporangiophores compared to other plant cells warrant further investigation into potential causes.
- This research contributes to a more accurate understanding of the optical characteristics of Phycomyces.
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