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AP-Biology Essay on vertebrate structural adaptations for terrestrial life. (From an actual past AP-BIOLOGY test) The problems of survival of animals on land are very different from those of survival of animals in aquatic environment. Describe four problems assoc ....

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.... is not present in all of the terrestrial environment. Terrestrial vertebrates have developed lungs to solve this problem. Air enters through the nasal passages, or the mouth, passes through the trachea, then branches off at the two bronchi, and goes through many branching passages called bronchioles, which end in alveoli. Alveoli are sack-like structures where the circulatory system meets the respiratory system. Since terrestrial vertebrates do not live in water, they need to develop a means of conserving water. One way we do this is through our excretions. Nitrogen forms a major waste product in animals. When amino acids and nucleic acids are broke ....