ASVAB ASVAB Certifications ASVAB-SECTION-7 Questions & Answers

• Question 121:

  Nitrates are very useful as __________.

  A. detergents

  B. fertilizers

  C. fuels

  D. solvents

  Correct Answer: B

  Explanation:

  The nitrogen in the soil must be replaced by nitrogen-fixing bacteria in the roots of legumes or by artificial

  fertilizer containing nitrates.

• Question 122:

  The reaction between sodium, metal, and water can be classified as __________.

  A. decomposition

  B. synthesis

  C. single replacement

  D. double replacement

  Correct Answer: C

  Explanation:

  2Na + 211011 -* 2Na()l I - IU is a single replacement reaction where one sodium atom replaces just one of

  the hydrogen atoms in each water molecule.

• Question 123:

  The number of atoms in a molecule of CuS()4 • 51 h is __________.

  A. 15

  B. 18

  C. 21

  D. 29

  Correct Answer: C

  Explanation:

  The hydrate CuS()4 • 51U contains 6 atoms in the salt C11SO4 (lCu + IS + 40). The five loosely bonded

  water molecules contain 15 atoms (10H + 5()). The total number of atoms is 6 + 15 = 21.

• Question 124:

  Which substance can be used to treat drinking water of questionable purity?

  A. ammonia

  B. chlorine

  C. hydrogen chloride

  D. iodine

  Correct Answer: D

  Explanation:

  Iodine crystals in a small bottle of water make a saturated aqueous solution. A few milliliters of this solution

  added to a quart of water will destroy most organisms in an hour.

• Question 125:

  A viral infection in humans that has a very long time between the initial exposure and the exhibiting of symptoms is __________.

  A. AIDS

  B. measles

  C. pneumonia

  D. chicken pox

  Correct Answer: A

  Explanation:

  A person exposed to the AIDS virus will take up to 6 months to show antibodies in the blood serum and 2

  to 5 years to show externally observable symptoms.

• Question 126:

  The beneficial relationship between termites and the protozoa that inhabit their digestive systems is called __________.

  A. symbiosis

  B. parthenogenesis

  C. mitosis

  D. phagocytosis

  Correct Answer: A

  Explanation:

  Symbiosis is a nutritive relationship in which organisms of different species live together and benefit each

  other.

• Question 127:

  Erosion and depletion are problems associated with __________.

  A. blood circulation

  B. baldness

  C. soil conservation

  D. cardiovascular exercise

  Correct Answer: C

  Explanation:

  Soil is eroded by the action of wind, water, and ice and/or is depleted by the removal of organic matter or

  minerals.

• Question 128:

  The glucose content of the blood is regulated by __________.

  A. insulin and adrenaline

  B. nerve stimulation

  C. ACTH

  D. progesterone

  Correct Answer: A

  Explanation:

  The relative concentration of glucose is maintained by the combined action of insulin from the pancreas

  and adrenaline from the adrenal medulla.

• Question 129:

  Blood circulation from the lungs goes directly to the __________.

  A. legs

  B. head

  C. heart

  D. digestive system

  Correct Answer: C

  Explanation:

  The pulmonary circulation returns oxygenated blood from the lungs through the pulmonary veins to the left

  atrium of the heart.

• Question 130:

  The end produces of protein digestion consists of __________.

  A. glucose

  B. fatty acids

  C. glycerol

  D. amino acids

  Correct Answer: D

  Explanation:

  Proteins are synthesized from a variety of amino acid "building blocks." Digestion breaks down the

  complex protein structures.