The lifespan of budding yeast cells is divided into two stages: reproductive and post-reproductive. The post-reproductive stage of the yeast's lifespan has never been characterized before. We have analyzed the influence of various mutations on the post-reproductive (PRLS) and replicative (RLS) lifespans. The results indicate that PRLS demonstrates an inverse relationship with RLS. The observed ...

We formulate a kinetic model of DNA replication that quantitatively describes recent results on DNA replication in the in vitro system of Xenopus laevis prior to the mid-blastula transition. The model describes well a large amount of different data within a simple theoretical framework. This allows one, for the first time, to determine the parameters governing the DNA replication program in a e...

Procedure 1. Place the specimen on a clean glass slide. Add 1 drop of 20% KOH. 2. Place the cover glass on top of the slide and gently press to get rid of any air bubbles. Blot excess solution from the finished slide preparation with the gauze. 3. Place slide on the microscope stage and start with a low-power (10 ×) examination. To make epithelial cells visible, reduce illumination by lowering ...