Pressure, temperature, and idk the last one:/
<span>The reason why the human body shivers when it is could is to
begin warming it up this is a natural reflex of the human body once it drops
below a certain temperature </span>
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Answer:
Explanation:
Pollen tubes are produced by the male gametophytes of seed plants. Pollen tubes act as conduits to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms.
