*Question*
Answer the following question given this paragraph: The first amino acid to be isolated was asparagine in 1806. It was obtained from protein found in asparagus juice (hence the name). Glycine, the major amino acid found in gelatin, was named for its sweet taste (Greek glykys, meaning "sweet"). In some cases an amino acid found in a protein is actually a derivative of one of the common 20 amino acids (one such derivative is hydroxyproline). The modification occurs after the amino acid has been assembled into a protein. Q: What was the first amino acid to be isolated? Choices: - histamine - histon - glutathione - asparagine A:
**Answer**
asparagine

*Question*
Answer the following question given this paragraph: Oil spills are another source of ocean pollution. To get at oil buried beneath the seafloor, oil rigs are built in the oceans. These rigs pump oil from beneath the ocean floor. Huge ocean tankers carry oil around the world. If something goes wrong with a rig on a tanker, millions of barrels of oil may end up in the water. The oil may coat and kill ocean animals. Some of the oil will wash ashore. This oil may destroy coastal wetlands and ruin beaches. Q: What source of ocean pollution kills animals by coating them? Choices: - plants spill - grain spill - chemical spill - oil spill A:
**Answer**
oil spill

*Question*
Answer the following question given this paragraph: For a better understanding of alkaline Earth metals, let's take a closer look at two of them: calcium (Ca) and strontium (Sr). Calcium is a soft, gray, nontoxic alkaline Earth metal. Although pure calcium doesn't exist in nature, calcium compounds are very common in Earth's crust and in sea water. Calcium is also the most abundant metal in the human body, occurring as calcium compounds such as calcium phosphate and calcium carbonate. These calcium compounds are found in bones and make them hard and strong. The skeleton of the average adult contains about a kilogram of calcium. Because calciumlike bariumabsorbs x-rays, bones show up white in x-ray images. Calcium is an important component of a healthy human diet. Good food sources of calcium are pictured in Figure below . Q: What is a soft, gray, nontoxic alkaline earth metal? Choices: - pewter - magnesium - potassium - calcium A:
**Answer**
calcium

*Question*
Answer the following question given this paragraph: Plants don't have immune systems, but they do respond to disease. Typically, their first line of defense is the death of cells surrounding infected tissue. This prevents the infection from spreading. Many plants also produce hormones and toxins to fight pathogens. For example, willow trees produce salicylic acid to kill bacteria. The same compound is used in many acne products for the same reason. Exciting new research suggests that plants may even produce chemicals that warn other plants of threats to their health, allowing the plants to prepare for their own defense. As these and other responses show, plants may be rooted in place, but they are far from helpless. Q: What do willow trees produce to kill bacteria? Choices: - chlorophyll - enzymes - cytoplasmic acid - salicylic acid A:
**Answer**
salicylic acid