Answer the following question given this paragraph: You can't go to the mantle but small pieces of the mantle can come to you. Kimberlite forms deep in the mantle and is erupted violently into the crust. Kimberlite can contain diamonds. Most kimberlites reached the surface much earlier in Earth history. Q: What is the upper most level of earth's layers called? Choices: - surface - volcanic - mantle - crust A:
crust
(Question)
Answer the following question given this paragraph: Catalysts may be classified as either homogeneous or heterogeneous. A homogeneous catalyst is uniformly dispersed throughout the reactant mixture to form a solution. Sulfuric acid, for example, is a homogeneous catalyst used in the synthesis of esters such as procaine (Example 13). An ester has a structure similar to that of a carboxylic acid, in which the hydrogen atom attached to oxygen has been replaced by an R group. They are responsible for the fragrances of many fruits, flowers, and perfumes. Other examples of homogeneous catalysts are the enzymes that allow our bodies to function. In contrast, a heterogeneous catalyst is in a different physical state than the reactants. For economic reasons, most industrial processes use heterogeneous catalysts in the form of solids that are added to solutions of the reactants. Because such catalysts often contain expensive precious metals such as platinum or palladium, it makes sense to formulate them as solids that can be easily separated from the liquid or gaseous reactantproduct mixture and recovered. Examples of heterogeneous catalysts are the iron oxides used in the industrial synthesis of ammonia and the catalytic converters found in virtually all modern automobiles, which contain precious metals like palladium and rhodium. Catalysis will be discussed in more detail in Chapter 14 "Chemical Kinetics" when we discuss reaction rates, but you will encounter the term frequently throughout the text. Q: What two ways may catalyst be classified? Choices: - oxygenated or heterogenous - reactive or nonreactive - fast or slow - homogeneous or heterogeneous A:
(Answer)
homogeneous or heterogeneous
Ques: Answer the following question given this paragraph: Outside of chromosome 21 and the sex chromosomes, most embryos with extra chromosomes do not usually survive. Because chromosomes carry many, many genes, a disruption of a chromosome can cause severe problems with the development of a fetus. Individuals with one (or more) fewer chromosome usually don't survive either. Can you explain why?. Q: Embryos usually don't survive if they have extra or too few of these genetic units? Choices: - phenotypes - genes - ribosomes - chromosomes A:
Ans: chromosomes
(Q).
Answer the following question given this paragraph: Seminiferous tubules can be seen in a cross section of a testis pictured in Figure below . The tubule is lined with spermatogonia, which are diploid, sperm-producing cells. Surrounding the spermatogonia are other cells. Some of these other cells secrete substances to nourish sperm, and some secrete testosterone, which is needed for sperm production. Q: What is secreted by the cells surrounding spermatogonia to help sperm production? Choices: - estrogen - dihydrotestosterone - follicle stimulating hormone - testosterone A:
(A).
testosterone
Ques:Answer the following question given this paragraph: Although migration is thought of as innate behavior, only some migrating species always migrate (obligate migration). Animals that exhibit facultative migration can choose to migrate or not. Additionally, in some animals, only a portion of the population migrates, whereas the rest does not migrate (incomplete migration). For example, owls that live in the tundra may migrate in years when their food source, small rodents, is relatively scarce, but not migrate during the years when rodents are plentiful. Foraging Foraging is the act of searching for and exploiting food resources. Feeding behaviors that maximize energy gain and minimize energy expenditure are called optimal foraging behaviors, and these are favored by natural section. The painted stork, for example, uses its long beak to search the bottom of a freshwater marshland for crabs and other food (Figure 45.36). Q: When a species always migrates, what is this type of migration called? Choices: - emigration - genus migration - mass migration - obligate migration A:

Ans:obligate migration
Answer the following question given this paragraph: There are two main types of air pollutants: primary and secondary. Most air pollutants come from burning fossil fuels. Some come from burning forests. Some are due to the evaporation of chemicals. Q: What are the two main types of air pollutants? Choices: - a and b - new and old - good and bad - primary and secondary A:
primary and secondary