Why do plant cells need chloroplasts?

Plants need chloroplast because this organelle produces a green pigment

called chlorophyll which is one of the essential components of

photosynthesis

Chloroplast produce a green pigment called chlorophyll which helps green

plants to trap the solar energy from the sun which is needed for biochemical

processes in plants.

An absence of the chloroplast means an absence of chlorophyll also and

photosynthesis being unable to hold.

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For photosynthesis

Explanation:

Photosynthesis is needed to make glucose for the plants.

what subject is this

the relative atomic mass of an element is the mass of one atom of that element, relative to 1/12th of the mass of a  1212c atom. to convert to an absolute mass in kg, it is necessary to multiply by  1.661×10−271.661×10−27.

the relative atomic mass is roughly equal to the number of neutrons, plus the number of protons, in the nucleus of the atom.

for elements with more than one stable isotope (different types of nucleus with different numbers of neutrons but the same number of protons), the quoted mass is usually the average mass, weighted by the relative abundance of the different isotopes.