*Question*
Q: Cells must also be able to separate their relatively stable interior from what? Read this paragraph and choose the correct option from the provided answers: Cells share the same needs: the need to get energy from their environment, the need to respond to their environment, and the need to reproduce. Cells must also be able to separate their relatively stable interior from the ever-changing external environment. They do this by coordinating many processes that are carried out within organelles, or other cellular structures. Structures that are common to many different cells indicate the common history shared by cell-based life. Examples of these common structures include the components of both the cell (or plasma) membrane and the cytoskeleton, and other structures shown in Figure above . Choices: - their habitat - predators - competition and chaos - the external environment A:
**Answer**
the external environment

*Question*
Q: Ultimately, most life forms get their energy from this? Read this paragraph and choose the correct option from the provided answers: Figure 4.2 Ultimately, most life forms get their energy from the sun. Plants use photosynthesis to capture sunlight, and herbivores eat the plants to obtain energy. Carnivores eat the herbivores, and eventual decomposition of plant and animal material contributes to the nutrient pool. Choices: - heat - earth - food - sun A:
**Answer**
sun

*Question*
Q: What kind of a reaction occurs when a substance reacts quickly with oxygen? Read this paragraph and choose the correct option from the provided answers: A combustion reaction occurs when a substance reacts quickly with oxygen (O 2 ). For example, in the Figure below , charcoal is combining with oxygen. Combustion is commonly called burning, and the substance that burns is usually referred to as fuel. The products of a complete combustion reaction include carbon dioxide (CO 2 ) and water vapor (H 2 O). The reaction typically gives off heat and light as well. The general equation for a complete combustion reaction is:. Choices: - invention reaction - Fluid Reaction - nitrogen reaction - combustion reaction A:
**Answer**
combustion reaction

*Question*
Q: What type of cellular respiration occurs in the presence of oxygen? Read this paragraph and choose the correct option from the provided answers: There are two types of cellular respiration (see Cellular Respiration concept): aerobic and anaerobic. One occurs in the presence of oxygen ( aerobic ), and one occurs in the absence of oxygen ( anaerobic ). Both begin with glycolysis - the splitting of glucose. Choices: - hyperbaric - anaerobic - extracellular - aerobic A:
**Answer**
aerobic