Figure 3.

Alternate DIC-fluorescence mode images of metaphase and anaphase in the same cell. (A) DIC mode image of a spermatocyte at metaphase made ∼25 min after a 2-s pulse injection of rh-tubulin. (B) In fluorescence mode, kinetochore fibers imaged with DIC in A appear speckled. (C and D) The same cell as in A and B undergoing anaphase A, during which kinetochore fibers shorten as autosomal half-bivalents segregate poleward. The two small sex univalents lag at the equator during anaphase A. Bar, 10 μm.