Answer:
On a graph, points are grouped closely together.
I only put one answer because the choices repeat.
Antartica and tropical areas.
If enough ejecta (mainly ash) is sent into the upper atmosphere, the dust particles will block solar energy causing a decrease in temperature. This has happened in the past. Look for the year without summer caused by a volcanic eruption.
The name comes from a latin word meaning to glue or bind together. DNA ligase catalyses the joining of DNA fragments (usually those produced by restriction enzymes). Thus different genes can be put into vectors and moved into other hosts.