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1. Membrane-bound organelles have been an important component in the evolution of complex, multicellular organisms. Which of the following best summarizes an advantage of eukaryotic cells having internal membranes? (A) Eukaryotic cells are able to reproduce faster because of the presence of organelles. (B) Some organelles, such as mitochondria and chloroplast, are similar to prokaryotic cells in structure. (C) Organelles isolate specific reactions, increasing metabolic efficiency (D) Compartmentalization leads to a higher mutation rate in DNA, which leads to more new species 2. By discharging electric sparks into a laboratory chamber atmosphere that consisted of water vapor, hydrogen gas, methane, and ammonia, Stanley Miller obtained data that showed that a number of organic molecules, including many amino acids, could be synthesized. Miller was attempting to model early Earth conditions as understood in the 1950s. The results of Miller’s experiments best support which of the following hypotheses? (A) The molecules essential to life today did not exist at the time Earth was first formed (B) The molecules essential to like today could not have boon carried to the primordial Earth by a comet or meteorite (C) The molecules essential to like today could have formed under early Earth conditions. (D) The molecules essential to life today were initially self-replicating proteins that were synthesized approximately four billion years ago. 5. Which of the following statements best supports the claim that organism share fundamental processes as a result of evolution? (A) All organisms that are introduced into new environments have the capacity to fill vacant ecological roles. (B) All organisms have the ability to utilize oxygen to harness energy from the chemical breakdown of organic compounds. (C) All organisms share a genetic code organized into triplet codons, making it possible for one organism to express a gene from another organism. (D) All organisms possess structures such as chloroplasts and mitochondria within their cells that reflect past symbiotic relationships between prokaryotic precursors. 21. In most freshwater fish, nitrogenous waste is primarily excreted and ammonia, which is highly soluble in water and is toxic at low concentrations. In terrestrial mammals, ammonia is converted to urea before it is excreted. Urea is also highly soluble in water but is less toxic than ammonia at low concentrations. Which of the following best explains why freshwater fish do NOT convert ammonia to urea for excretion? (A) The metabolic pathways of fish do not normally involve nitrogen consumption. (B) The dilution of ammonia by direct excretion into freshwater conserves energy (C) Ammonia is concentrated in tissues, where it is stored prior to excretion. (D) The nitrogen in ammonia is recycled for use in protein and nucleotide synthesis 24. Which of the following statements most directly supports the claim that different species of organisms use different metabolic strategies to meet their energy requirements for growth, reproduction, and homeostasis? (A) During cold periods pond-dwelling animals can increase the number of unsaturated fatty acids in their cell membranes while some plants make antifreeze protein to prevent ice crystal formation in tissues. (B) Bacteria lack introns while many eukaryotic genes contain many of these intervening sequences. (C) Carnivores have more teeth that are specialized for ripping food while herbivores have more teeth that are specialized for grinding food. (D) Plants generally use starch molecules for storage while animals user glycogen and fats for storage. 31. The endocrine system incorporates feedback mechanisms that maintain homeostasis. Which of the following demonstrates negative feedback by the endocrine system? (A) During labor, the fetus exerts pressure on the uterine wall, induction the production of oxytocin =, which stimulates uterine wall contraction. The contraction cause the fetus to futher push on the wall, increa