Proteins are polymers, relatively large molecules made form many smaller molecules. Each protein molecules is built up from amino acids, smaller monomer molecules that join end to end to make the protein polymers molecule. <span />
The three observations that could help an individual in distinguising whether the organism is a fish or not is that it should live under water as fish can't survive without water, another thing is that it should laid eggs when it comes to giving birth because when it does not lay eggs but produces a living organism normally without an egg, it is considered to be a mammal and lastly, the appearance it possess such as having gils or fins.
The respiratory system contains the lungs, so the answer is C. Hope this helps.
Answer:
Saudi Arabia, Russia, the United States, and Iran
Explanation:
Blood enter the right atrium of the heart via the vena cava (superior and inferior)
The right atrium contracts to push the blood into the right ventricle through the triscupid valve
The contraction of the right ventricle pushes the blood through the pulmonary valve to the pulmonary artery which carries it to the lungs to be oxygenated
After oxygenation, the pulmonary vein brings blood to the left atrium
Contraction of the left atrium pushes the blood through the mitral valve into the left ventricle
The left ventricle contracts to push the blood through the aortic valve, into the aorta, which carries the blood through the body.