The answer is a “rises because it is less dense than cold air”
Protein synthesis occurs in the cytoplasm, specifically in the ribosomes. Proteins that are meant to be excreted, such as in the pancreas, are produced in the rough endoplasmic reticulum which is a membrane studded with ribosomes. In organs that primarily function to produce and secrete proteins, there will be a larger rough endoplasmic reticulum with more ribosomes.
I am going to assume you meant "chloroplasts" instead of "Hloroplasts"
Your answer will be plant cells
Chloroplasts makes the energy for the plant by conducting photosynthesis, therefore, they are only found in plant cells.
The southern hemisphere would be experiencing winter :)