The answer is <span>insect and pest populations decreased.
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DDT (dichlorodiphenyltrichloroethane) was used as an insecticide which is a substance used to kill insects. That resulted in decrease in insect and pest populations. It is a persistent and non-degradable insecticide, but as well organic pollutant readily accumulated to soils and consequently affects organisms.
The correct answer is mRNA.
mRNA or messenger RNA is synthesized during the process of transcription, from DNA molecule which is used as a template. mRNA contains information about protein synthesis (translation) in the form of nucleotide triplets or codons.
In the example above: reference book is DNA molecule (template for copies), copies are mRNA, wood is amino acids (building blocks) and doghouse is protein.
Injecting.
smoking.
inhaling.
snorting.
swallowing.
Answer:
a series of pools built like steps to enable fish to bypass a dam or waterfall.
Explanation:
A fish ladder, also known as a fishway, fish pass or fish steps, is a structure on or around artificial and natural barriers to facilitate diadromous fishes' natural migration.