Answer the following question given this paragraph: View this animation (http://openstaxcollege. org/l/ headblow) to see how a blow to the head may produce a contrecoup (counterblow) fracture of the basilar portion of the occipital bone on the base of the skull. Why may a basilar fracture be life threatening? 3. Osteoporosis is a common age-related bone disease in which bone density and strength is decreased. Watch this video (http://openstaxcollege. org/l/osteoporosis) to get a better understanding of how thoracic vertebrae may become weakened and may fractured due to this disease. How may vertebral osteoporosis contribute to kyphosis? 4. Watch this animation (http://openstaxcollege. org/l/ diskslip) to see what it means to "slip" a disk. Watch this second animation (http://openstaxcollege. org/l/ herndisc) to see one possible treatment for a herniated disc,. Q: What is a common age-related bone disease in which bone density and strength is decreased? Choices: - fibrosis - lupus - arthritis - osteoporosis A:
osteoporosis
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Answer the following question given this paragraph: In science, motion is defined as a change in position. An object's position is its location. Besides the wings of the hummingbird in the opening image, you can see other examples of motion in the Figure below . In each case, the position of something is changing. Q: In science, what is defined as a change in position? Choices: - gravity - speed - direction - motion A:
motion
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Answer the following question given this paragraph: Q: Does climate change have a positive or negative effect on reproductive success? Choices: - neither - positive - both - negative A:
negative
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Answer the following question given this paragraph: Radiation can be absorbed or shielded by materials, such as the lead aprons dentists drape on us when taking x rays. Lead is a particularly effective shield compared with other materials, such as plastic or air. How does the range of radiation depend on material? Ionizing radiation interacts best with charged particles in a material. Since electrons have small masses, they most readily absorb the energy of the radiation in collisions. The greater the density of a material and, in particular, the greater the density of electrons within a material, the smaller the range of radiation. Collisions Conservation of energy and momentum often results in energy transfer to a less massive object in a collision. This was discussed in detail in Work, Energy, and Energy Resources, for example. Different types of radiation have different ranges when compared at the same energy and in the same material. Alphas have the shortest range, betas penetrate farther, and gammas have the greatest range. This is directly related to charge and speed of the particle or type of radiation. At a given energy, each , , or will produce the same number of ionizations in a material (each ionization requires a certain amount of energy on average). The more readily the particle produces ionization, the more quickly it will lose its energy. The effect of charge is as follows: The has a charge of +2q e , the has a charge of q e , and the . Q: Radiation can be absorbed or shielded by materials, particularly what material used to make protective aprons worn by x-ray administrators? Choices: - cotton - steel - carbon - lead A:
lead
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