The organelle that carries out photosynthesis and produces gas is the chloroplast.

Here's why:

* Photosynthesis: Chloroplasts contain chlorophyll, the green pigment that absorbs light energy from the sun. This energy is used to convert carbon dioxide and water into glucose (sugar) and oxygen.

* Gas Production: During photosynthesis, chloroplasts release oxygen as a byproduct. This oxygen is what we breathe and is essential for many life forms.

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