Answer the following question given this paragraph: Nitrates, salts of nitric acid, form when metals, oxides, hydroxides, or carbonates react with nitric acid. Most nitrates are soluble in water; indeed, one of the significant uses of nitric acid is to prepare soluble metal nitrates. Nitric acid finds extensive use in the laboratory and in chemical industries as a strong acid and strong oxidizing agent. It is important in the manufacture of explosives, dyes, plastics, and drugs. Salts of nitric acid (nitrates) are valuable as fertilizers. Gunpowder is a mixture of potassium nitrate, sulfur, and charcoal. The reaction of N2O3 with water gives a pale blue solution of nitrous acid, HNO2. However, HNO2 (shown in Figure 18.51) is easier to prepare by the addition of an acid to a solution of nitrite; nitrous acid is a weak acid, so the nitrite ion is basic in aqueous solution: NO 2 (aq) + H 3 O +(aq) HNO 2(aq) + H 2 O(l) Nitrous acid is very unstable and exists only in solution. It disproportionates slowly at room temperature (rapidly when heated) into nitric acid and nitric oxide. Nitrous acid is an active oxidizing agent with strong reducing agents, and strong oxidizing agents oxidize it to nitric acid. Q: What is a mixture of potassium nitrate, sulfur, and charcoal? Choices: - gasoline - cyanide - TNT - gunpowder A:
gunpowder
(Question)
Answer the following question given this paragraph: Government policies and laws are needed to protect biodiversity. Such actions have been shown to work in the past. For example, peregrine falcons made an incredible recovery after laws were passed banning the use of DDT. Q: Peregrine falcons made an incredible recovery after laws were passed banning the use of what? Choices: - Carbaryl - miticide - Acetamiprid - ddt A:
(Answer)
ddt
Ques: Answer the following question given this paragraph: years or more. During this time, a girl's height can increase 3 inches a year. The next step in puberty is menarche, the start of menstruation. In boys, the growth of the testes is typically the first physical sign of the beginning of puberty, which is followed by growth and pigmentation of the scrotum and growth of the penis. The next step is the growth of hair, including armpit, pubic, chest, and facial hair. Testosterone stimulates the growth of the larynx and thickening and lengthening of the vocal folds, which causes the voice to drop in pitch. The first fertile ejaculations typically appear at approximately 15 years of age, but this age can vary widely across individual boys. Unlike the early growth spurt observed in females, the male growth spurt occurs toward the end of puberty, at approximately age 11 to 13, and a boy's height can increase as much as 4 inches a year. In some males, pubertal development can continue through the early 20s. Q: In boys, what hormone stimulates the growth of the larynx and thickening and lengthening of the vocal folds, which causes the voice to drop in pitch during puberty? Choices: - Sexual - Endocrine - Petuitary - testosterone A:
Ans: testosterone
(Q).
Answer the following question given this paragraph: Q: Glycolysis oxidizes glucose to two molecules of pyruvate? Choices: - N/A - see below - N/A - see below - N/A - see below - glucose A:
(A).
glucose
Ques:Answer the following question given this paragraph: The placenta takes over the synthesis and secretion of progesterone throughout pregnancy as the corpus luteum degenerates. Like estrogen, progesterone suppresses FSH and LH. It also inhibits uterine contractions, protecting the fetus from preterm birth. This hormone decreases in late gestation, allowing uterine contractions to intensify and eventually progress to true labor. The placenta also produces hCG. In addition to promoting survival of the corpus luteum, hCG stimulates the male fetal gonads to secrete testosterone, which is essential for the development of the male reproductive system. The anterior pituitary enlarges and ramps up its hormone production during pregnancy, raising the levels of thyrotropin, prolactin, and adrenocorticotropic hormone (ACTH). Thyrotropin, in conjunction with placental hormones, increases the production of thyroid hormone, which raises the maternal metabolic rate. This can markedly augment a pregnant woman's appetite and cause hot flashes. Prolactin stimulates enlargement of the mammary glands in preparation for milk production. ACTH stimulates maternal cortisol secretion, which contributes to fetal protein synthesis. In addition to the pituitary hormones, increased parathyroid levels mobilize calcium from maternal bones for fetal use. Q: What takes over the synthesis and secretion of progesterone throughout pregnancy as the corpus luteum degenerates? Choices: - vagina - uterus - ovaries - placenta A:

Ans:placenta
Ques: Answer the following question given this paragraph: Macroevolution occurs over geologic time above the level of the species. The fossil record reflects this level of evolution. It results from microevolution taking place over many generations. Q: Microevolution occuring and taking place over many generations results in? Choices: - fission - microinjection - recalibration - macroevolution A:
Ans:
macroevolution