Continental collision is a phenomenon of the plate tectonics of Earth that occurs at convergent boundaries. Continental collision is a variation on the fundamental process of subduction, whereby the subduction zone is destroyed, mountainsproduced, and two continents sutured together. Continental collision is known only to occur on Earth.
Continental collision is not an instantaneous event, but may take several tens of millions of years before the faulting and foldingcaused by collisions stops. The collision between India and Asia has been going on for about 50 million years already and shows no signs of abating. Collision between East and West Gondwana to form the East African Orogen took about 100 million years from beginning (610 Ma) to end (510 Ma). Collision between Gondwana and Laurasia to form Pangea occurred in a relatively brief interval, about 50 million years long.
Answer:
C
Explanation:
The origin of replication refers to the site at which DNA replication begins. The process of DNA replication - which occurs prior to cell division - generates a new copy of the DNA.
DNA replication involves unwinding of the DNA double helix, creating a Y shape called the replication fork. The two strands are then replicated, and now there are two DNA molecules, each containing one "old" DNA strand and one "new" DNA strand.
The first stage at the origin of replication is that the enzyme helicase begins splitting apart the strands of a DNA molecule. (C)
The answer is not A, as the two DNA strands are already in the double helix. The answer is not B, as the enzyme responsible for copying the DNA sequence is DNA polymerase, not RNA polymerase. The answer also cannot be D, because although short RNA primers are involved in DNA replication, this does not occur at the origin of replication.
C..........................................................................................................................................
