Answer:
Cold fronts form when a cooler air mass moves into an area of warmer air in the wake of a developing extratropical cyclone. The warmer air interacts with the cooler air mass along the boundary, and usually produces precipitation
Hello,
PCR is a useful technique because it is used to amplify small segments of DNA.
Thanks,
Answer:
Explanation:
1)Pfr/Pr
2) Pr
3)far-red
Explanation:
The leaves at the top of a tree’s canopy are exposed to direct sunlight during the day, and their phytochromes will occur in a high *Pfr/Pr* ratio. Meanwhile, the leaves of the same tree at the bottom of the canopy are highly shaded during the day and will likely have a higher proportion of the * ( PHYTOCHROME )Pr *;form of phytochrome present due to exposure to a higher proportion of *FAR RED * light.
Plants make use of the phytochrome system to it's adjust growth based on the seasons. Through phytochrome plants is able to respond to the timing and duration of dark and light periods. At dawn, all the phytochrome molecules present in the leaved are converted to the active Pfr form until sunset this is because the sun is unfiltered, and unfiltered sunlight has high percentage of red light, but lower far-red light, with the help of phytochrome system , the plants is able to compare the length of dark periods over several days.
Changes in the dna are called mutations. They can occur spontaneously. Mutations can only be passed down in gametes--sperm and egg cells. with Darwins theory at mind a mutation needs to pass the test of natural selection to remain in the gene pool. So purposly making mutation or altercations may end in diseases/illnesses or in some cases death because they body can not take it.....hope this helps if it doesnt im sorry!