Q: Q: What is the microtubule-organizing center found near the nuclei of animal cells? Read this paragraph and choose the correct option from the provided answers: Animal Cells versus Plant Cells At this point, you know that each eukaryotic cell has a plasma membrane, cytoplasm, a nucleus, ribosomes, mitochondria, peroxisomes, and in some, vacuoles, but there are some striking differences between animal and plant cells. While both animal and plant cells have microtubule organizing centers (MTOCs), animal cells also have centrioles associated with the MTOC: a complex called the centrosome. Animal cells each have a centrosome and lysosomes, whereas plant cells do not. Plant cells have a cell wall, chloroplasts and other specialized plastids, and a large central vacuole, whereas animal cells do not. The Centrosome The centrosome is a microtubule-organizing center found near the nuclei of animal cells. It contains a pair of centrioles, two structures that lie perpendicular to each other ( Figure 4.15). Each centriole is a cylinder of nine triplets of microtubules. Choices: - lysosome - spliceosome - entrosome - centrosome A:
A: centrosome

Q: Q: Distillation is an effective method to separate mixtures comprised of two or more what? Read this paragraph and choose the correct option from the provided answers: Distillation is an effective method to separate mixtures comprised of two or more pure liquids. Distillation is a purification process in which the components of a liquid mixture are vaporized (transformed from liquid to gas) and then condensed (transformed from gas back to liquid) and isolated. In a simple distillation, a mixture is gradually heated. The solution with the lowest boiling point will change into a gas first. This gas, or vapor, then passes through a cooled tube (a condenser) where it condenses back into its liquid state. This condensed liquid is called the distillate. Figure below illustrates this. Choices: - solutes - ionic compounds - elements - pure liquids A:
A: pure liquids

Q: Q: What type of flowers offer no reward, such as nectar, to a male wasp? Read this paragraph and choose the correct option from the provided answers: Choices: - vines - perennials - roses - ophrys A:
A: ophrys

Q: Q: When a solution freezes, only what particles come together to form a solid phase, while the presence of solute particles interferes with that process? Read this paragraph and choose the correct option from the provided answers: The presence of solute particles has the opposite effect on the freezing point of a solution. When a solution freezes, only the solvent particles come together to form a solid phase, and the presence of solute particles interferes with that process. Therefore, for the liquid solvent to freeze, more energy must be removed from the solution, which lowers the temperature. Thus, solutions have lower freezing points than pure solvents do. This phenomenon is called freezing point depression. For every mole of particles in a liter of water, the freezing point decreases by about 1.9C. Both boiling point elevation and freezing point depression have practical uses. For example, solutions of water and ethylene glycol (C2H6O2) are used as coolants in automobile engines because the boiling point of such a solution is greater than 100C, the normal boiling point of water. In winter, salts like NaCl and CaCl2 are sprinkled on the ground to melt ice or keep ice from forming on roads and sidewalks. This is because the solution made by dissolving sodium chloride or calcium chloride in water has a lower freezing point than pure water, so the formation of ice is inhibited. Choices: - pigment - hydrogen - diluent - solvent A:
A: solvent