As part of an early experiment on the secretory system, an in vitro translation system consisting only of mRNA and ribosomes resulted in secretory proteins that were larger than the identical protein when translated in a cell. Why?

Alternative splicing of secretory protein mRNAs requires additional proteins not included in the in vitro system.

Explanation:

Alternative splicing is a cellular process that produces messenger RNAs (mRNAs) with different sizes and therefore proteins with different lengths. This cellular process requires the presence of specific cofactors that enables to remove introns and select exons in the precursor mRNA (pre-mRNA)

A prominence refers to a bright, large, gaseous feature projecting externally from the surface of the Sun, usually in a loop shape. Prominences are attached with the surface of the Sun in the photosphere and elongate outwards into the corona of the Sun.

The prominences are related to the discharge of the high energy constituents called a solar flare. These solar flares have been considered to influence electronic communication as their energy blends up the upper atmosphere of the Earth, making the radio transmissions weak and noisy.

Hence, the correct statements are prominences can disturb radio communications on Earth and prominences are loop-shaped.