A student working in a laboratory that studies the difference between eukaryotic and prokaryotic ribosomes finds a tube in the lab that is simply labeled "purified ribosomes." The lab manager tasks the student with determining the identity of the ribosomes in the tube. The student centrifuges the contents of the tube through a cesium chloride gradient under conditions that separate the small and large ribosomal subunits from each other. At the conclusion of the experiment, the student notes that there are four primary bands in the cesium chloride gradient, with all four bands ranging between approximately 30 and 60S. What is a logical conclusion that can be drawn from this data?
1. Only prokaryotic ribosomes are in the sample.
2. Only eukaryotic ribosomes are present in the sample.
3. There are no ribosomes in the sample.
4. There is a combination of both prokaryotic and eukaryotic ribosomes in the sample.

The sedimentation rate of eukaryotic ribosomes is 80S (60S for larger subunit and 40S for smaller subunit ) while the sedimentation rate of prokaryotic ribosomes is 70S ( 50S for the larger subunit and 30S for the smaller subunit )

As in the above mentioned scenario , all the bands on the cesium chloride gradient ranges from 30 to 60S , they contain both prokaryotic as well as eukaryotic ribosomes .