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Bacteria doubles. Two goes to four, goes to eight, goes to 16, goes to 32. And in 24 hours, we have 2 to the 72 microbes sitting there. They obviously have the capacity to divide very, ver...

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Another of the large air ships exploded high in the air.Members of the crew fell to the ground.The huge ship lost control and began turning again and again.Soon it was close to the ground.The warriors...

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So this is HIV. It's a typical retrovirus, meaning that it has an outer envelope. And in the center, it has two copies of RNA, as well as an enzyme, here in blue. That's reverse tran...

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We're going to first look at the right ventricle atrium connection in which cells are being brought out of the low-oxygen starved body and being pumped into the lungs. And if we look at...

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Let's review how HIV's reverse transcriptase works. The yellow strand is HIV RNA; it's attached to the reverse transcriptase enzyme. Reverse transcriptase uses the hosts cell nucleotides....

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So when HIV buds from a cell, it's not in a mature form. Its proteins are actually in a multilinked chain, so protease comes in and cleaves the proteins, in several different places. So...

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This video was prepared by my colleagues Dieter Egli and Kevin Eggan. And you see here, on the left is what's called a holding pipette, which gently sucks on the egg. The egg is surroun...

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The creature with the spear was huge.There were many other similar creatures.They had ridden behind me on the backs of large animals.Each of them carried a collection of strange-looking weapons.The on...