Q: Proto-oncogenes are positive cell-cycle regulators but when mutated, they can become what? Read this paragraph and choose the correct option from the provided answers: Watch this animation (http://openstaxcollege. org/l/p53_cancer) to learn more about the use of p53 in fighting cancer. Proto-oncogenes are positive cell-cycle regulators. When mutated, proto-oncogenes can become oncogenes and cause cancer. Overexpression of the oncogene can lead to uncontrolled cell growth. This is because oncogenes can alter transcriptional activity, stability, or protein translation of another gene that directly or indirectly controls cell growth. An example of an oncogene involved in cancer is a protein called myc. Myc is a transcription factor that is aberrantly activated in Burkett's Lymphoma, a cancer of the lymph system. Overexpression of myc transforms normal B cells into cancerous cells that continue to grow uncontrollably. High B-cell numbers can result in tumors that can interfere with normal bodily function. Patients with Burkett's lymphoma can develop tumors on their jaw or in their mouth that interfere with the ability to eat. Choices: - microbes and cause cancer - bacteria and cause cancer - cultigens and cause cancer - oncogenes and cause cancer A:
oncogenes and cause cancer
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Q: Shortening of muscle fibers is called what?' Read this paragraph and choose the correct option from the provided answers: Each muscle in the body is made up of cells called muscle fibers. Muscle fibers are long, thin cells that can do something that other cells cannot dothey are able to get shorter. Shortening of muscle fibers is called contraction . Muscle fibers can contract because they are made of proteins, called actin and myosin, that form long filaments (or fibers). When muscles contract, these protein filaments slide or glide past one another, shortening the length of the cell. When your muscles relax, the length extends back to the previous position. Nearly all movement in the body is the result of muscle contraction. Choices: - diffusion - diffusion - shrinking - contraction A:
contraction
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Q: What kind of compounds change color when bases come into contact with them, so they can be used to detect bases? Read this paragraph and choose the correct option from the provided answers: Certain compounds, called indicators, change color when bases come into contact with them, so they can be used to detect bases. An example of an indicator is a compound called litmus. It is placed on small strips of paper that may be red or blue. If you place a few drops of a base on a strip of red litmus paper, the paper will turn blue. You can see this in the Figure below . Litmus isn't the only detector of bases. Red cabbage juice can also detect bases, as you can see in this video: http://www. youtube. com/watch?v=vrOUdoS2BtQ . Choices: - liquid - parameters - metals - indicators A:
indicators
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Q: What is manufactured and added to foods to preserve freshness? Read this paragraph and choose the correct option from the provided answers: A type of lipid called trans fat is found in many processed foods. Trans fat is rare in nature but is manufactured and added to foods to preserve freshness. Eating foods that contain trans fat increases the risk of heart disease. Trans fat may be found in such foods as cookies, doughnuts, crackers, fried foods, ground beef, and margarine. Choices: - carbohydrates - vitamin c - protein - trans fat A:
trans fat
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