NEETBotanyCell - The Unit of Life
An organelle is composed of structural RNAs and about 80 different proteins. Which of the following is a correct characteristic of this organelle?
Options
- AIts sedimentation coefficient is a direct measure of its density and size
- BThe outer nuclear membrane usually bears this organelle on its surface
- CIt possesses a larger subunit of 50S in the eukaryotic cytoplasm
- DIt is the major site for the synthesis of steroidal hormones in animal cells
Correct answer
B. The outer nuclear membrane usually bears this organelle on its surface
Step-by-step solution
The organelle described is the ribosome, as it is composed of structural RNA and about 80 different proteins. The outer nuclear membrane usually remains continuous with the endoplasmic reticulum and also bears ribosomes on it. Thus, this is a correct characteristic. The Svedberg's unit (sedimentation coefficient) is an indirect, not direct, measure of density and size. Eukaryotic ribosomes (80S) have a larger subunit of 60S, not 50S. The synthesis of steroidal hormones in animal cells occurs in the smooth endoplasm