In what part of the plant does photosynthesis usually take place

Photosynthesis usually take place in the chlorophyll present in the leaves.

Explanation:

Leaves comprise of a structure named as chlorophyll.

The chlorophyll can be described as structures which are responsible for giving the leaves its green colour.

A structure present in the chlorophyll, termed as chloroplast, is the site where photosynthesis occurs. Chloroplast is the organelle which is responsible for trapping all the sunlight required for photosynthesis. Glucose and energy i.e ATP  are made as a result of photosynthesis. The chloroplast is also the site where the energy molecules are stored.

not only is it colder, it also becomes darker, less salty, and more dense.