Problem: OPTIONS:
- concentration of repressor protein
- binding of expressor protein
- the addition of water
- nonbinding of repressor protein
Q: Answer the following question given this paragraph: When lactose is present, the repressor protein does not bind to the operator. This allows RNA polymerase to bind to the promoter and begin transcription. As a result, the lac genes are expressed, and lactose is digested. Q: When lactose is present in the cell, what allows the lac genes to be expressed? A:
Answer: nonbinding of repressor protein

Problem:OPTIONS:
- spring waves
- spring floods
- spring storms
- spring tides

Answer the following question given this paragraph: Spring tides occur during the new moon and full moon. The Sun and Moon must either be in a straight line on the same side of Earth, or they must be on opposite sides of Earth. Their gravitational pull combines to cause very high and very low tides. Spring tides have the greatest tidal range. Q: What occurs during the new moon and full moon, due to gravitational pull? A:
****
A: spring tides

Answer the following question given this paragraph: Physical and chemical properties of geometric isomers are generally different. While cis -2-butene is a polar molecule, trans -2-butene is nonpolar. Heat or irradiation with light can be used to bring about the conversion of one geometric isomer to another. The input of energy must be large enough to break the pi bond between the two carbon atoms, which is weaker than the sigma bond. At that point, the now single bond is free to rotate and the isomers can interconvert. Q: Physical and chemical properties of geometric isomers are generally what? A:
OPTIONS:
- round
- difficult
- similar
- different
different

Answer the following question given this paragraph: Unsaturated hydrocarbons that contain one or more triple bonds are called alkynes . The names of specific alkynes always end in yne and have a prefix for the number of carbon atoms. The structural formula in the Figure below represents the smallest alkyne, named ethyne, which has two carbon atoms and two hydrogen atoms (C 2 H 2 ). Ethyne is also called acetylene. It is burned in acetylene torches, like the one pictured in the Figure below . The flame of an acetylene torch is so hot that it can melt metal. Q: Alkynes are what type of compound? A:
OPTIONS:
- reversible hydrocarbons
- proteins hydrocarbons
- Split Hydrocarbons
- unsaturated hydrocarbons

Answer: unsaturated hydrocarbons

Question: Answer the following question given this paragraph: General Cnidarian Life Cycle. Cnidarians may reproduce both asexually and sexually. Q: What are two ways cnidarians are able to reproduce? A:
OPTIONS:
- mitosis and meiosis
- spawning and sexual
- internally and externally
- asexually and sexually
Answer: asexually and sexually

input: OPTIONS:
- helium
- nitrogen
- carbon
- oxygen Now, answer this question: Answer the following question given this paragraph: Occurrence, Preparation, and Compounds of Boron and Silicon Boron constitutes less than 0.001% by weight of the earth's crust. In nature, it only occurs in compounds with oxygen. Boron is widely distributed in volcanic regions as boric acid, B(OH)3, and in dry lake regions, including the desert areas of California, as borates and salts of boron oxyacids, such as borax, Na2B4O710H2O. Elemental boron is chemically inert at room temperature, reacting with only fluorine and oxygen to form boron trifluoride, BF3, and boric oxide, B2O3, respectively. At higher temperatures, boron reacts with all nonmetals, except tellurium and the noble gases, and with nearly all metals; it oxidizes to B2O3 when heated with concentrated nitric or sulfuric acid. Boron does not react with nonoxidizing acids. Many boron compounds react readily with water to give boric acid, B(OH)3 (sometimes written as H3BO3). Reduction of boric oxide with magnesium powder forms boron (9598.5% pure) as a brown, amorphous powder: B 2 O 3(s) + 3Mg(s) 2B(s) + 3MgO(s) An amorphous substance is a material that appears to be a solid, but does not have a long-range order like a true solid. Treatment with hydrochloric acid removes the magnesium oxide. Further purification of the boron begins with conversion of the impure boron into boron trichloride. The next step is to heat a mixture of boron trichloride and hydrogen: 1500 C. Q: Boron only occurs naturally in compounds with what element? A:
A:
output:
oxygen