Question: Q: Scientists perform experiments to test their hypotheses because sometimes the nature of natural universe is what? Read this paragraph and choose the correct option from the provided answers: Scientists perform experiments to test their hypotheses because sometimes the nature of natural universe is not obvious. Choices: - become obvious - very obvious - this obvious - not obvious A:
Answer: not obvious

Question: Q: Hyperparathyroidism results from an overproduction of what? Read this paragraph and choose the correct option from the provided answers: Hyperparathyroidism results from an overproduction of parathyroid hormone. This results in excessive calcium being removed from bones and introduced into blood circulation, producing structural weakness of the bones, which can lead to deformation and fractures, plus nervous system impairment due to high blood calcium levels. Hypoparathyroidism, the underproduction of PTH, results in extremely low levels of blood calcium, which causes impaired muscle function and may result in tetany (severe sustained muscle contraction). The hormone calcitonin, which is produced by the parafollicular or C cells of the thyroid, has the opposite effect on blood calcium levels as does PTH. Calcitonin decreases blood calcium levels by inhibiting osteoclasts, stimulating osteoblasts, and stimulating calcium excretion by the kidneys. This results in calcium being added to the bones to promote structural integrity. Calcitonin is most important in children (when it stimulates bone growth), during pregnancy (when it reduces maternal bone loss), and during prolonged starvation (because it reduces bone mass loss). In healthy nonpregnant, unstarved adults, the role of calcitonin is unclear. Choices: - inhibited hormone - tharayroid hormone - elevated hormone - parathyroid hormone A:
Answer: parathyroid hormone

Question: Q: What is the term for animals that have a backbone? Read this paragraph and choose the correct option from the provided answers: The first eight phyla listed in Table above include only invertebrate animals. Invertebrates are animals that lack a vertebral column , or backbone . The last phylum in the table, the Chordata, also includes many invertebrate species. Tunicates and lancelets are both invertebrates. Altogether, invertebrates make up at least 95 percent of all animal species. The remaining animals are vertebrates. Vertebrates are animals that have a backbone. All vertebrates belong to the phylum Chordata . They include fish, amphibians, reptiles, birds, and mammals. Choices: - carnivores - invertebrates - herbivores - vertebrates A:
Answer:
vertebrates