<span>Desertification is the cancer of the earth,” Argentine geographer Elena Abraham told IPS. “It is a process of degradation that does not manifest itself in spectacular ways but furtively advances, and by the time it is visible there is nothing to be done, and people have to move away, in search of an alternative.”</span>
Persistent chlorinated hydrocarbon pesticides persist in the environment and accumulate in the foods chain causing harmful effects on the environment including posing a threat to humans health in the long term. Nonpersistent organophosphate pesticides are more toxic than the former but degrade after a short life span. Therefore they cause immediate harm in case one is in contact with them.
The fact that they do not accumulate in the environment, they are more favourable than chlorinated hydrocarbon pesticides. Chlorinated hydrocarbon pesticides will affect several generations due to their accumulation in the environment. However they don't need to be re-applied hence are less expensive
Answer:
The Answer is Herbivores
Explanation:
Herbivores are considered Primary Consumers because the organisms that eat the producers are the primary consumers. They tend to be small in size and there are many of them.
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.
A photograph of all the stained, prepared chromosomes in a eukaryotic cell is referred to as a karyotype
