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A phylogenetic tree showing the major eukaryotic supergroups.
Cardiac catheterization. Insertion of a tube called a catheter through a blood vessel. In this examp
Earth’s history is divided into nested sets of time--eons, eras, periods, and epochs--and is called
Cutaway Drawing of Tholos, The So-called Treasury of Atreus
Descending limbs of Hadley cells are the sites of the world’s major deserts
The nucleus is bounded by a double membrane called the nuclear envelope