1. What causes the tectonic plates to move? 2. How did the creator of this video explain why
some plates are moving faster than others?
3. What are the 3 main types of plate boundaries?

1. The heat from radioactive processes within the planet's interior causes the plates to move, sometimes toward and sometimes away from each other. This movement is called plate motion, or tectonic shift. 2. But scientists were at a loss to explain why some pieces of crust move much faster than others. A new study suggests these tectonic plates control their own speed more than the mantle does. ... The velocities of these plates and the velocities of the boundaries between these plates vary significantly on Earth." 3. Divergent boundaries -- where new crust is generated as the plates pull away from each other.

Convergent boundaries -- where crust is destroyed as one plate dives under another.

Transform boundaries -- where crust is neither produced nor destroyed as the plates slide horizontally past each other.

Explanation:

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.