Biology

What was first responsible for changing the formerly poisonous atmosphere to an oxygen-rich atmosphere, as we have today?
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When an enzyme is involved in a catabolic reaction A. its active site binds the substrates and changes shape, stressing the bond, lowering the activation energy, and breaking the bond. B. its active site binds the substrates and changes shape, bringing them close together, lowering the activation energy, and creating a bond. C. its active site binds the substrates and changes shape, stressing the bond, increasing the activation energy, and breaking the bond. D. its active site binds the substrates and changes shape, creating a bond by increasing the activation energy. E. None of the above.
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Zooplankton get their energy fromphytoplanktongrassesphotosynthesissmall fish
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What type of stress is most likely to occur at thisboundary?O shearingsynclinetensioncompression
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Which equation best represents the process of photosynthesis
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) During the germinal period, the fertilized ovum duplicates and forms a blastocyst. This hollow ball of cells ________.a. fills the amnion with fluidb. develops a tail for movementc. contains the embryonic diskd. shrinks in size and is absorbed by the blood
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Use the following words in multiple sentences to show your understanding of how they connect together.
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Which of the following types of solutions should be used when preparing a wet mount? (Circle one.) a. hypertonic b.hypotonic c.isotonic
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the following is an example of an indirect observation? A. using tools such as a thermometer or rain gauge to take measurements B. counting rings on a tree stump to determine its age C. counting the number of bald eagles that land near a river D. using a live video to observe nesting owls
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what type of commensal relationship is orchids growing on branches of trees ?
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How is dna molecule replicated
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Proteins are constantly being synthesized in a living cell. Why doesn't the number of protein molecules become too great for the cell to contain, leading to cell destruction?
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The images show two species of tree frogs in a particular region.The gray tree frogs are adapted to the trees of the woodlands, while the green tree frogs can survive in woodlands or grasslands. The gray frog was abundant in the woodlands. Because of climatic changes, most of the trees in the region died, and the woodlands changed to grasslands. In such a case, the .The gray tree frog is closely related to the green tree frog genetically, but they have different mating calls. This suggests that specia
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How have modern advancements allowed this modern-day scientist to do research in a way that Darwin couldn't?
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How does energy get transferred from the Sun to a cow?
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Dr. Haxton says the O-O bond is polar and the C-C bond is nonpolar. A good student would say ... a. No, both bonds are highly polar. b. Right! O is electronegative, so O2 is polar. c. Yes. O attracts electrons more strongly than C. d. No way. C is more electronegative than O. d. Wrong again, Ralph. Both bonds are nonpolar.
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Which disease is distinguished by the presence of reed-sternberg cells?
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Pollution from a single, identifiable source is called source pollution.
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Several factors influence the rate of diffusion and among these factors are temperature, ____________ , electrical currents, and molecular size. For example, as temperature ____________ , the rate of diffusion increases.
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What is malaria ?
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Which of the following Gametes can be formed from the following genotype: TtYy.A. YY B. tYC. tyD. TYE. TyF. Tt
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Why are estuaries, such as the Pamlico Estuary, so important?
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When Elaine accidentally touched the hot stove, she immediately pulled her hand away without even having to think about it. This seemingly automatic movement of her hand could not have been possible without the effective operation of the ______________ nervous system.
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Active transport requires energy because it usually involves the movement of A. substances from an area of low concentration to an area of high concentration. B. substances from an area of high concentration to an area of low concentration. C. substances in the gas phase, such as oxygen and carbon dioxide. D. substances that can easily pass through the cell membrane, such as water.
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