Answer the following question given this paragraph: The nitrogen cycle moves nitrogen back and forth between the atmosphere and organisms. Bacteria change nitrogen gas from the atmosphere to nitrogen compounds that plants can absorb. Other bacteria change nitrogen compounds back to nitrogen gas, which re-enters the atmosphere. Q: The nitrogen cycle moves nitrogen back and forth between the atmosphere and what? Choices: - Ocean - Ozone Layer - sediments - organisms A:
organisms

Answer the following question given this paragraph: Carbon's affinity for covalent bonding means that many distinct and relatively stable organic molecules nevertheless readily form larger, more complex molecules. Any large molecule is referred to as macromolecule (macro- = "large"), and the organic compounds in this section all fit this description. However, some macromolecules are made up of several "copies" of single units called monomer (mono- = "one"; -mer = "part"). Like beads in a long necklace, these monomers link by covalent bonds to form long polymers (poly- = "many"). There are many examples of monomers and polymers among the organic compounds. Monomers form polymers by engaging in dehydration synthesis (see Figure 2.14). As was noted earlier, this reaction results in the release of a molecule of water. Each monomer contributes: One gives up a hydrogen atom and the other gives up a hydroxyl group. Polymers are split into monomers by hydrolysis (-lysis = "rupture"). The bonds between their monomers are broken, via the donation of a molecule of water, which contributes a hydrogen atom to one monomer and a hydroxyl group to the other. Q: Any large molecule is referred to as what? Choices: - cellular - microtubule - polymer - macromolecule A:
macromolecule

Answer the following question given this paragraph: The deep-water zone is dark so there is no photosynthesis. Most deep-water organisms are scavengers. They feed on dead organisms that fall to the bottom of the lake. Crabs and catfish are two of these types of organisms. Fungi and bacteria are decomposers that live in the deep zone. Q: Why does photosynthesis not occur in the deep-water zone? Choices: - it is cold - it is pressurized - it is stagnant - it is dark A:
it is dark

Answer the following question given this paragraph: Primates are generally divided into prosimian and non-prosimian primates. Q: What are generally divided into prosimian and non-prosimian? Choices: - carnivores - rodents - insects - primates A:
primates