Q: Answer the following question given this paragraph: Indeed, scientists discovered something astonishing. Many times in Earth's history, the magnetic poles have switched positions. North becomes south and south becomes north! When the north and south poles are aligned as they are now, geologists say it is normal polarity. When they are in the opposite position, they say that it is reversed polarity. Q: What feature of the land do contour lines show? Choices: - trails - flat surfaces - bodies of water - three-dimensional shape A:
A: three-dimensional shape

Q: Answer the following question given this paragraph: The speed of sound also depends on the temperature of the medium. For a given medium such as air, sound has a slower speed at lower temperatures. You can compare the speed of sound in air at different temperatures in Table below . A lower temperature means that particles of the medium are moving more slowly, so it takes them longer to transfer the energy of the sound waves. The amount of water vapor in the air affects the speed of sound as well. Do you think sound travels faster or slower when the air contains more water vapor? ( Hint: Compare the speed of sound in water and air in Table above . ). Q: The amount of water vapor in the air and the temperature of the medium affects how fast what travels? Choices: - colour - light - traffic - sound A:
A: sound

Q: Answer the following question given this paragraph: Peroxisomes Like lysosomes, a peroxisome is a membrane-bound cellular organelle that contains mostly enzymes (Figure 3.17). Peroxisomes perform a couple of different functions, including lipid metabolism and chemical detoxification. In contrast to the digestive enzymes found in lysosomes, the enzymes within peroxisomes serve to transfer hydrogen atoms from various molecules to oxygen, producing hydrogen peroxide (H2O2). In this way, peroxisomes neutralize poisons such as alcohol. In order to appreciate the importance of peroxisomes, it is necessary to understand the concept of reactive oxygen species. Q: Peroxisomes perform a couple of different functions, including lipid metabolism and chemical detoxification. in contrast to the digestive enzymes found in lysosomes, the enzymes within peroxisomes serve to transfer hydrogen atoms from various molecules to oxygen, producing what? Choices: - calcium - water - hydrogen - hydrogen peroxide A:
A: hydrogen peroxide

Q: Answer the following question given this paragraph: Eukaryotic cells also contain other organelles besides the nucleus. An organelle is a structure within the cytoplasm that performs a specific job in the cell. Organelles called mitochondria, for example, provide energy to the cell, and organelles called vacuoles store substances in the cell. Organelles allow eukaryotic cells to carry out more functions than prokaryotic cells can. Q: What is the term for a structure within the cytoplasm that performs a specific job in the cell? Choices: - mitochondria - nucleus - ribosome - organelle A:
A: organelle