What is the difference between "free" and "attached" ribosomes?
A) Free ribosomes are in the cytoplasm, whereas attached ribosomes are anchored to the endoplasmic reticulum.
B) Free ribosomes produce proteins in the nucleus, whereas attached ribosomes produce proteins in the cytoplasm.
C) Free ribosomes produce proteins that are exported from the cell, whereas attached ribosomes make proteins for mitochondria and chloroplasts.
D) Free ribosomes are found in prokaryotes, whereas attached ribosomes are found in eukaryotes.
E) Free ribosomes function in protein synthesis, whereas attached ribosomes function in protein modification.

Question

Quizplus · Accepted Answer

Free ribosomes are not attached to the endoplasmic reticulum, and are instead located in the cytoplasm. Attached ribosomes are anchored to the endoplasmic reticulum.

Answer: C
 Free ribosomes produce proteins that remain in the cytoplasm, while attached ribosomes make proteins for export, for insertion into the plasma membrane or lysosomal membrane, or for use inside lysosomes, peroxisomes, and other organelles. Ribosomes associated with the endoplasmic reticulum also make proteins that will be transported into mitochondria or chloroplasts.

Note that options B, D, and E are incorrect.

What Is the Difference Between "Free" and "Attached" Ribosomes