Atrna molecule has an at the top and an at the bottom

amino acid and RNA (or anticodon)

tRNA is used in the process of translation, which is when cells create a protein (polypeptide) from a strand of mRNA just came from the nucleus and is floating in the cytoplasm. This process occurs with the help of ribosomes!

A ribosome binds to an mRNA molecule, and tRNA's come swooping in one at a time to add amino acids to a growing polypeptide chain (protein).

On one end of the tRNA is a set of 3 RNA bases (called an anticodon), that binds perfectly to the opposing next 3 bases on the mRNA strand (called a codon) as it works it way through the ribosome. On the other side of the tRNA is the amino acid that the codon on the mRNA codes for, thus allowing the specific protein to grow 1 amino acid at a time.

***see attached pic***

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.