What is the function of the organelle labeled A in the diagram?

Protein synthesis actually begins in the nucleus when transcribes a single gene on the dna molecule is copied. the process of copying this gene is called this copy is known as and contains the protein building instructions. this copy is sent out into the cytoplasm to the part of the cell known as the the of the ribosome will join together to form a functional ribosome when they attach to the mrna. as the mrna moves through the ribosome, the message is read by transfer rna brings the correct back to the ribosome. the amino acids are placed in the correct order and are hitched together by

The organelle pictured is found in cells of and is theorized to have once been an independent organism.

This is the main structural axis of the plant that supports leaves, flowers and fruits; transports fluids; stores nutrients and produces new tissue.