Ribosomes are essential for protein synthesis but they are present in mitochondria and plastids , the sites of respiration and photosynthesis . What is the role of ribosomes in those organelles ?
A. Ribosomes transport ATP formed in respiration and photosynthesis to cytoplasm through ER
B. Subunits of some required proteins are synthesised in these organelles
C. Ribosomes transport RNA and DNA to cytoplasm
D. All the above correct
