Question

which part of a plant other than root hair cell does not contain chloroplasts and why?

Answer 1

All plant cells don’t contain chloroplasts. The plant’s entire body isn’t green, just the green parts you can see with the naked eye - the leaves, of course, and sometimes stems. Besides the roots, which you mentioned, the trunk and branches of trees, bushes, and some small plants aren’t green; nor are the flowering parts, usually. Then, when you go down to the microscopic level, you see structures within the leaves that contain no chloroplasts.

Mainly the chlorophyll-containing chloroplasts are located in the leaves, between the clear (thus no chlorophyll) epidermal layers. The epidermal layers are translucent, so light can enter. Which also allows us to see them, making the plant look green to our eyes. The area where they are is called the palisade layer, and below it, the spongy layer.