Why Should A Potometer be Allowed to stand before starting the Experiment​

It is crucial to avoid air bubbles in the assembled potometer. The plant stem must be cut under water to prevent airlocks forming in the xylem. All fittings must be tight so that the only way the apparatus can lose water is by the plant transpiring.

The soviet union beat the us to the first successful launch, with the october 4, 1957, orbiting of sputnik 1, and later beat the us to have the first human in earth orbit, yuri gagarin, on april 12, 1961. the "race" peaked with the july 20, 1969, us landing of the first humans on the moon with apollo 11

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