Plants have chloroplasts and mitochondria. What is the purpose of mitochondria when a cell already has chloroplasts? To turn sugars into energy
To fight off infection
To help plants store water
To store vitamins

To turn sugars into energy

Explanation:

Mitochondria are main sites of aerobic respiration. They are miniature biochemical factories where food stuffs are completely oxidised to carbon dioxide and water. The energy (ATP) produced in the mitochondria helps to perform various energy requiring processes. Because of the formation of ATP in mitochondria it is called power house of the cell.

Photosynthesis: Light reaction (in thylakoids), Dark reaction (in stroma).Storage of starch.

1. is through mitosis2.dna replication

The open ocean begins at the low-tide mark and extends to the end of the continental shelf

above statement is not a true statement about the open ocean because the open ocean has low levels of nutrients. most of the photosynthetic activity on earth occurs in the open ocean within the photic zone. organisms in the deep ocean are exposed to frigid temperatures and total darkness but it does not begin at the low-tide mark.