D. barometer would be the correct answer.
Pollen tubes are produced by the male gametophytes of seed plants. They 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
Answer:
You can look at the DNA under an electron microscope and analyze it
Explanation:
what else would you do with DNA eat it? Feed it to your dog?
Answer:
A pesar de algunas observaciones tempranas de bacterias y células, el microscopio impactó otras ciencias, especialmente la botánica y la zoología, más que la medicina. Importantes mejoras técnicas en la década de 1830 y posteriormente corregir la mala óptica, transformando el microscopio en un poderoso instrumento para ver los microorganismos causantes de enfermedades.
Explanation: