When the Ribosome Reaches a Stop Codon on the MRNA

question 22

Multiple Choice

When the ribosome reaches a stop codon on the mRNA, no corresponding tRNA enters the A site. If the translation reaction were to be experimentally stopped at this point, which of the following would you be able to isolate?

• A) an assembled ribosome with a polypeptide attached to the tRNA in the P site
• B) separated ribosomal subunits, a polypeptide, and free tRNA
• C) an assembled ribosome with a separated polypeptide
• D) separated ribosomal subunits with a polypeptide attached to the tRNA
• E) a cell with fewer ribosomes

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Definitions:

Ethmoid

The ethmoid bone is a spongy, cuboid-shaped bone situated between the eyes and forming part of the cranial base and the nasal cavity walls.

Lacrimal

Related to tears or the glands that produce tears.

Superior Articular Facet

The upper part of a vertebra that connects with an adjacent vertebra, contributing to the spine's flexibility and movement.

Posterior Sacral Foramina

Posterior sacral foramina are openings on the dorsal side of the sacrum that allow for the passage of nerves and blood vessels to the pelvic organs and lower limbs.