Answer:
Venus and Mercury are the only planets in our solar system that do not have moons. Venus and Mercury have a gravitational pull that is weaker than the gravitational pull of the Sun, so they wouldn't be able to hold onto their own moon.
It is unchanged and can be used again for the same chemical reaction.
is the answer
Answer: topoisomerases
Explanation:
Topoisomerases are enzymes that help overwind or underwind DNA. DNA double helix has high tedency to get winded again because of its structural characeristics.
During replication and transcription of DNA, DNA gets overwound in front of a replication fork. This enzyme stops the double helix of DNA from becoming too tightly bound in front of the replication fork as the DNA opens.
The given demonstartion shows the action of topoisomerases as it shows unwinding of of supercoiled strands of pipe (DNA), which is don eby topoisomerases in the DNA replication process.
Hence, the correct answer is topoisomerases.
