Ribosomes in the cytoplasm of a bacterium are of which type?

Explanation

Prokaryotic ribosomes are 70S, made of a 50S and a 30S subunit, while eukaryotic cytoplasmic ribosomes are 80S. Antibiotics such as streptomycin and tetracycline bind the 70S ribosome and leave the host's 80S ribosomes alone, which is why they kill bacteria without killing the patient. Mitochondria and chloroplasts also contain 70S ribosomes, evidence for the endosymbiotic theory.