Dicer-deficient oocytes stained for beta-tubulin and DNA to visualize the meiotic spindle. DNA was counterstained with Sytox green. In the absence of Dicer, mouse oocytes develop abnormal spindles and often fail to complete the first meiotic division, revealing a novel role for small RNAs during meiosis.
Escherichia coli cells with fluorescently labeled chromosomal loci.
motility mutants stab-inoculated on a 0.3% agar motility plate. The “halos” and
“rings” likely reflect the motility of this archaeon following gradients of
attractant or repellent chemicals.
Malaria parasites (and their kin) can be viewed as minimal eukaryotes, harboring a nucleus (yellow), a secretory pathway the Golgi (purple) and specialized ‘rhotpry’ organelle (black), and two endosymbiotic organelles, the mitochondrion (red) and apicoplast (green).
Siberian Larch, taken at our field site near Lake Khovsgol in north-central Mongolia. We are analyzing tree-ring width and stable isotopes of the tree rings to reconstruct climate, and Larch responses to climate change, over the past century as the temperature in Mongolia has risen.
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