Q: What is the substance called whenatoms of different elements join together? Read this paragraph and choose the correct option from the provided answers: Did you ever make cupcakes from scratch? You mix together flour, sugar, eggs, and other ingredients to make the batter, put the batter into cupcake papers, and then put them into the oven to bake. The cupcakes that come out of the oven after baking are different from any of the individual ingredients that went into the batter. Like the ingredients that join together to make cupcakes, atoms of different elements can join together to form entirely different substances called compounds. In cupcakes, the eggs and other wet ingredients cause the dry ingredients to stick together. What causes elements to stick together in compounds? The answer is chemical bonds. Choices: - crusts - crystals - plants - compounds A:
compounds

Q: Aging is associated with the death of what? Read this paragraph and choose the correct option from the provided answers: Aging is associated with the death of cells. Give two reasons why cells die. Choices: - proteins - genes - muscles - cells A:
cells

Q: Which theory explains how populations of organisms can change over time? Read this paragraph and choose the correct option from the provided answers: The theory of evolution by natural selection explains how populations of organisms can change over time. As environments change, so must the traits of organisms if they are to survive in the new conditions. Evolution by natural selection explains how this happens. It also explains why there are so many different species of organisms on Earth today. You can see examples of the incredible diversity of living animals in Figure below . You can read more about the theory of evolution in the chapter Evolution. Choices: - free by natural selection - changes by natural selection - intelligent selection - evolution by natural selection A:
evolution by natural selection

Q: Glaciers modify the landscape by what? Read this paragraph and choose the correct option from the provided answers: Glaciers modify the landscape by erosion. They also modify the landscape by deposition. Glaciers carry an enormous amount of material and dump it. The features they leave behind show where they were and what happened as they were melting away. Choices: - silt - sediment - truncation - erosion A:
erosion