DNA helicase untwists the helix at the replication origins. Then the DNA is seperated into a "Y" shape called the replication fork.
This is true , trees loose their leaves as a part of growth, also in seasons they loose leaves.
a. chloroplast and cell wall
The chloroplast contains chlorophyll, which is the stuff that makes plants green. So animals do not have a chloroplast. Only plants have a cell wall and it is what helps plants maintain their shape. Hope this helped! :)
