Robin can have a ddt concentration of 444ppm while the ddt concentration of soil is 10 ppm. This happens due to biological magnification.
<u>Explanation:</u>
In biological magnification the concentration of toxic substances at successive trophic levels keeps increasing. Due to biomagnification, what starts out as a small concentration grows while moving to successive trophic levels. DDT is a pesticide which is used to kill pests that affect crops.
DDT used in farms gets deposited in the soil. From the soil it can reach various trophic levels. At each trophic level its concentration keeps increasing.
Robin is a bird that is a secondary consumer and thus belongs to the higher trophic level. Thus even if the DDT concentration is as low as 10ppm in the soil its concentration will keep increasing and can become a high value like 444ppm.
ATP is produced in the Calvin cycle
I think it’s loss of ozone layer
All of the above are needed. Nucleotides are the basic building blocks of new DNA, ATP energy is needed because replication is an active process, and enzymes catalyze the reactions needed to carry it out (e.g. helicase to separate the strands to be replicated, DNA polymerase to build the new strands, and ligase to "glue" the fragments together).
Parietal cells produce gastric acid (hydrochloric acid) in response to histamine (via H2 receptors), acetylcholine (M3 receptors) and gastrin (gastrin receptors). Parietal cells contain an extensive secretory network (called canaliculi) from which the HCl is secreted by active transport into the stomach.
