Structure of mitochondrial ribosomes?

Question

Is the ribosome found in mitochondrion and choloroplast formed of 30S and 50S subunits as in prokaryotes. I couldn't find any information on internet concerning it.The general wikipedia page has no information about it though it says>The ribosomes found in chloroplasts and mitochondria of eukaryotes also consist of large and small subunits bound together with proteins into one 70S particle.[9] These organelles are believed to be descendants of bacteria (see Endosymbiotic theory) and, as such, their ribosomes are similar to those of bacteria.

Answer 1

Hi, great question!

Yes, ribosomes found in the mitochondrion and chloroplast of eukaryotic cells are also 70S and consist of a small 30S subunit and a large 50S subunit. We think this is due to the theory that mitochondria and chloroplasts were once separate cells that became incorporated into their respective cells in a symbiotic relationship.

Answer 2

The mitochondrial ribosome in mammals consists of a 28S small subunit, rather than the 30S small subunit found in the cytoplasmic ribosome, and a 39S large subunit, rather than the 50S subunit. Therefore, the mitochondrial ribosome is a 55S structure.