Answer the following question given this paragraph: Protein Structure. Primary protein structure is the sequence of amino acids in a single polypeptide. Secondary protein structure refers to internal shapes, such as alpha helices and beta pleated sheets, that a single polypeptide takes on due to bonds between atoms in different parts of the polypeptide. Tertiary protein structure is the overall three-dimensional shape of a protein consisting of one polypeptide. Quaternary protein structure is the shape of a protein consisting of two or more polypeptides. For a brief animation of protein structure, see www. stolaf. edu/people/giannini/flashanimat/proteins/protein%20structure. swf . Q: A sequence of amino acids in single polypeptide is the primary structure for what? Choices: - lipids - cells - dna - proteins A:
proteins
Answer the following question given this paragraph: In the winter, the temperature often gets well below the freezing point of water. This condition can create problem in car radiators. If the water freezes, water hoses will break, the engine block can crack, and significant damage can be done to the car. Q: In winter, water does what, becoming solid and causing hoses to rupture and engine blocks to crack? Choices: - crystallizes - shrinks - fractures - freeze A:
freeze
Q: Answer the following question given this paragraph: Further away from the heart, the aorta branches into smaller arteries, which eventually branch into capillaries. Capillaries are the smallest type of blood vessel; they connect very small arteries and veins. Gases and other substances are exchanged between cells and the blood across the very thin walls of capillaries. Q: What are the smallest type of blood vessel? Choices: - varicose veins - spider veins - arteries - capillaries A:
A: capillaries
Question: Answer the following question given this paragraph: Over 99 percent of all species that ever lived on Earth have gone extinct. Five mass extinctions are recorded in the fossil record. They were caused by major geologic and climatic events. Evidence shows that a sixth mass extinction is occurring now. Unlike previous mass extinctions, the sixth extinction is due to human actions. Q: What percentage of all species that ever lived on earth have gone extinct? Choices: - 25% - 50% - 93 % - 99% A:
Answer: 99%
*Question*
Answer the following question given this paragraph: Long bones are longer than they are wide and have a shaft and two ends. The diaphysis, or central shaft, contains bone marrow in a marrow cavity. The rounded ends, the epiphyses, are covered with articular cartilage and are filled with red bone marrow, which produces blood cells (Figure 38.17). Most of the limb bones are long bonesfor example, the femur, tibia, ulna, and radius. Exceptions to this include the patella and the bones of the wrist and ankle. Q: What is contained in the cavity of a long bone's central shaft? Choices: - blood - calcium - cells - marrow A:
**Answer**
marrow
(Q).
Answer the following question given this paragraph: Did you ever see a cat chase after a laser light, like the one in Figure below ? A laser is a device that produces a very focused beam of visible light of just one wavelength and color. Waves of laser light are synchronized so the crests and troughs of the waves line up. The diagram in Figure below shows why a beam of laser light is so focused compared with ordinary light from a flashlight. Q: What do you call a device that produces a very focused beam of visible light of just one wavelength and color? Choices: - optical diffuser - fusion relay - light meter - laser A:
(A).
laser