Ques:Answer the following question given this paragraph: Chemical weathering is different than mechanical weathering. The minerals in the rock change. The rock changes composition and becomes a different type of rock. Most minerals form at high pressure or high temperatures deep within Earth. But at Earth's surface, temperatures and pressures are much lower. Minerals that were stable deeper in the crust are not stable at the surface. That's why chemical weathering happens. Minerals that formed at higher temperature and pressure change into minerals that are stable at the surface. Chemical weathering is important. It starts the process of changing solid rock into soil. We need soil to grow food and create other materials we need. Chemical weathering works through chemical reactions that change the rock. Q: What type of weathering causes the minerals in a rock to change? Choices: - toxic - natural - artificial - chemical A:

Ans:chemical
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Ques:Answer the following question given this paragraph: There are 20 amino acids that make up proteins. With three bases per codon, there are 64 possible codons. This is more than enough to code for the 20 amino acids plus start and stop signals. You can see how to translate the genetic code in Figure below . Start at the center of the chart for the first base of each three-base codon. Then work your way out from the center for the second and third bases. Q: How many different amino acids make up proteins. Choices: - 14 - 25 - 30 - 20 A:

Ans:20
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Ques:Answer the following question given this paragraph: Proteins play many important roles in living things. Some proteins help cells keep their shape, and some make up muscle tissues. Many proteins speed up chemical reactions in cells. Other proteins are antibodies, which bind to foreign substances such as bacteria and target them for destruction. Still other proteins carry messages or materials. For example, human red blood cells contain a protein called hemoglobin, which binds with oxygen. Hemoglobin allows the blood to carry oxygen from the lungs to cells throughout the body. A model of the hemoglobin molecule is shown in Figure below . Q: What type of proteins bind to foreign substances and attempt destruction? Choices: - membranes - ribosomes - antigens - antibodies A:

Ans:antibodies
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Ques:Answer the following question given this paragraph: Q: During what are deletions and duplications especially likely to occur? Choices: - nucleus - endothermia - electrolysis - meiosis A:

Ans:
meiosis
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