where does the head of the rib attach
Rib cage Each rib consists of a head, neck, and a shaft, and they are numbered from top to bottom. The head of a rib is the end part closest to the spine with which it articulates. It is marked by a kidney-shaped articular surface which is divided by a horizontal crest into two facets. The superior facet is smaller and articulates with the vertebra above, and the inferior facet articulates with the vertebra of the same number. The transverse process of a thoracic vertebra also articulates with the rib of the same number. The crest gives attachment to the intra-articular ligament.[3] All ribs are attached posteriorly to the thoracic vertebrae.
Ribosome In Figure 5, both ribosomal subunits (small and large) assemble at the start codon (towards the 5' end of the RNA). The ribosome uses RNA that matches the current codon (triplet) on the mRNA to append an amino acid to the polypeptide chain. This is done for each triplet on the RNA, while the ribosome moves towards the 3' end of the mRNA. Usually in bacterial cells, several ribosomes are working parallel on a single RNA, forming what is called a polyribosome or polysome.