Birefringence of Amœbæ

  title={Birefringence of Am{\oe}b{\ae}},
  author={J. M. Mitchison},
IT has been known for some time that the cell membrane of an amœba in water is birefringent. The optical axis lies radially, and the sign is positive with respect to the tangent1 (Fig. 1). I have found that if an Amœba proteus is fixed for about 10 min. in 4 per cent formalin and then immersed in a solution of potassium mercuric iodide of refractive index 1.56, the birefringence of the membrane decreases, and the sign becomes negative (Fig. 2). A similar increase in the negative birefringence… 
Thickness and Structure of the Membrane of the Human Red Cell Ghost
It is now known that there is only enough lipoid present in a ghost to form a continuous layer over the surface about 50–100 A. thick when dry, and the strength of the birefringence was such that it must have been due to a layer of lipoid many molecules in thickness.
Molecular Orientation at the Surface of Amoebae during Pinocytosis
By means of fluorescein-labelled proteins, Brandt5 demonstrated that proteins inducing pinocytosis are attached to the cell membrane of Amoebae and Schumaker obtained results on the rate of uptake of radioactive proteins which lead to a similar conclusion.
Optical Changes in the Membranes of the Sea-Urchin Egg at Fertilization, Mitosis and Cleavage
1. Changes in birefringence and light scattering of the sea-urchin egg membranes at fertilization, mitosis and cleavage are described and illustrated. 2. There is a close similarity between the
Polarization microscopy with the LC-PolScope
This is the author's version of the work that was published in Live Cell Imaging : A Laboratory Manual, edited by R. D. Goldman and D. Spector, 2005.
KontraktilitÄt und Ultrastruktur glycerin-extrahierter Fibroblasten aus der Gewebekultur
Chick heart fibroblasts outgrown from heart explants of nine-day embryos were glycerol-extracted for 1/2 hour, 1 and 12 days to maintain the relaxed state of an intracellular contractile system.