(Q).
Answer the following question given this paragraph: When light is refracted its wavelength and speed change; however, its frequency remains the same as the frequency of the light source. Proof of this is that light retains its original color under water. For example, blue light is still blue under water. Q: Light retains its original color under water because what remains the same when light is refracted? Choices: - wave length - density - sound - frequency A:
(A).
frequency

(Q).
Answer the following question given this paragraph: Denaturation and Protein Folding Each protein has its own unique sequence and shape that are held together by chemical interactions. If the protein is subject to changes in temperature, pH, or exposure to chemicals, the protein structure may change, losing its shape without losing its primary sequence in what is known as denaturation. Denaturation is often reversible because the primary structure of the polypeptide is conserved in the process if the denaturing agent is removed, allowing the protein to resume its function. Sometimes denaturation is irreversible, leading to loss of function. One example of irreversible protein denaturation is when an egg is fried. The albumin protein in the liquid egg white is denatured when placed in a hot pan. Not all proteins are denatured at high temperatures; for instance, bacteria that survive in hot springs have proteins that function at temperatures close to boiling. The stomach is also very acidic, has a low pH, and denatures proteins as part of the digestion process; however, the digestive enzymes of the stomach retain their activity under these conditions. Protein folding is critical to its function. It was originally thought that the proteins themselves were responsible for the folding process. Only recently was it found that often they receive assistance in the folding process from protein helpers known as chaperones (or chaperonins) that associate with the target protein during the folding process. They act by preventing aggregation of polypeptides that make up the complete protein structure, and they disassociate from the protein once the target protein is folded. Q: An example of irreversible denaturation of what substance occurs to the liquid albumin when an egg is fried? Choices: - bacterial - acids - liquid - protein A:
(A).
protein

(Q).
Answer the following question given this paragraph: Almost all plants make food by photosynthesis. Only about 1 percent of the estimated 300,000 species of plants have lost the ability to photosynthesize. These other species are consumers, many of them predators. How do plants prey on other organisms? The Venus fly trap in Figure below shows one way this occurs. Q: What is the process by which almost all plants make food? Choices: - reactions - digestion - melting - photosynthesis A:
(A).
photosynthesis