Answer:
The correct answer is B. DNA helicase first unwinds the double helix around the +1 site.
Explanation:
The helicase is an enzyme that specifically breaks the hydrogen bonds of the bases in the transcription process. As E. Coli is a prokaryote, then, the transcription only occurs in one point of the circular DNA. The promoter region indicates where the DNA polymerase has to start replicating and the Topoisomerase unwinds the parts of the DNA that are being excessively twisted because of the separation of the two strands.
Answer: Unlike the one way flow of energy, matter is recycled within and between ecosystems.
Explanation:
The best answer is A
Saltwater fish are hypotonic to their surroundings. This means their blood has a higher water concentration than the surrounding sea water.
Due to the fact that there is more salt and less water outside their bodies, there is a tendency to take in salt and lose water.
To counter this, salt water fish drink a lot of the sea water and urinate very little. Special cells in the gills actively eliminate salt at the cost of extra energy and these fishes do not absorb any salt from the water they drink.
