Answer the following question given this paragraph: At the beginning of the reaction, only the reactants A and B are present. Recall that over the course of a reaction, the reaction rate slows down. This is because the rate depends on the concentrations of one or more reactants. As the reactants are used up, their concentrations drop, thus decreasing the reaction rate. Q: What happens to the reaction rate over the course of a reaction? Choices: - reverses - stays the same - speeds up - slows down A:
slows down
Answer the following question given this paragraph: 4.3 | Connective Tissue Supports and Protects By the end of this section, you will be able to: Identify and distinguish between the types of connective tissue: proper, supportive, and fluid Explain the functions of connective tissues As may be obvious from its name, one of the major functions of connective tissue is to connect tissues and organs. Unlike epithelial tissue, which is composed of cells closely packed with little or no extracellular space in between, connective tissue cells are dispersed in a matrix. The matrix usually includes a large amount of extracellular material produced by the connective tissue cells that are embedded within it. The matrix plays a major role in the functioning of this tissue. The major component of the matrix is a ground substance often crisscrossed by protein fibers. This ground substance is usually a fluid, but it can also be mineralized and solid, as in bones. Connective tissues come in a vast variety of forms, yet they typically have in common three characteristic components: cells, large amounts of amorphous ground substance, and protein fibers. The amount and structure of each component correlates with the function of the tissue, from the rigid ground substance in bones supporting the body to the inclusion of specialized cells; for example, a phagocytic cell that engulfs pathogens and also rids tissue of cellular debris. Q: Connective tissues typically have three characteristic components in common: cells, large amounts of amorphous ground substance, and what else? Choices: - antioxidants - hormones - white blood cells - protein fibers A:
protein fibers
Q: Answer the following question given this paragraph: Deposition as a change of state often occurs in nature. For example, when warm moist air comes into contact with very cold surfacessuch as the ground or objects on the groundice crystals are deposited on them. These ice crystals are commonly called frost. Look at the dead leaf and blades of grass in the Figure below . They are covered with frost. If you look closely, you can see the individual crystals of ice. You can watch a demonstration of frost forming on the side of a very cold can at the URL below. (Click on the mulitmedia choice "Ice on a Can. "). The ice in the can has been cooled to a very low temperature by adding salt to it. If you want to do the demonstration yourself, follow the procedure at the URL. http://www. middleschoolchemistry. com/lessonplans/chapter2/lesson4. Q: What are the ice crystals that form on the ground called? Choices: - snow - granules - sleet - frost A:
A: frost
Question: Answer the following question given this paragraph: The strength of an acid depends on how many hydrogen ions it produces when it dissolves in water. A stronger acid produces more hydrogen ions than a weaker acid. For example, sulfuric acid (H 2 SO 4 ), which is found in car batteries, is a strong acid because nearly all of it breaks down into ions when it dissolves in water. On the other hand, acetic acid (CH 3 CO 2 H), which is the acid in vinegar, is a weak acid because less than 1 percent of it breaks down into ions in water. Q: The strength of an acid depends on how many of which ions it produces when it dissolves in water? Choices: - silicon - carbon - helium - hydrogen A:
Answer: hydrogen
*Question*
Answer the following question given this paragraph: Comets are small, icy objects that have very elliptical orbits around the Sun. Their orbits carry them from the outer solar system to the inner solar system, close to the Sun. Early in Earth's history, comets may have brought water and other substances to Earth during collisions. Q: What are small, icy objects that have very elliptical orbits around the sun? Choices: - meteors - craters - asteroids - comets A:
**Answer**
comets
*Question*
Answer the following question given this paragraph: 39.2 Gas Exchange across Respiratory Surfaces The lungs can hold a large volume of air, but they are not usually filled to maximal capacity. Lung volume measurements include tidal volume, expiratory reserve volume, inspiratory reserve volume, and residual volume. The sum of these equals the total lung capacity. Gas movement into or out of the lungs is dependent on the pressure of the gas. Air is a mixture of gases; therefore, the partial pressure of each gas can be calculated to determine how the gas will flow in the lung. The difference between the partial pressure of the gas in the air drives oxygen into the tissues and carbon dioxide out of the body. Q: Tidal volume, expiratory reserve volume, inspiratory reserve volume, and residual volume are all types of what kind of measurement? Choices: - respiratory volume - emitted volume - breathing volume - lung volume A:
**Answer**
lung volume