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growing roots in isolation.c. how plants can be grown without roots.d. what elements are necessary for the growth of plants.62. the underlined word themselves in paragraph 1 refers to ______a. plant physiologists b. solutionsc. laboratory flasks d. roots63. the scientists found what the isolated roots need is ______a. quite naturalb. sugar, minerals and vitaminsc. some rare vitaminsd. organic nitrogen pounds64. roots have the ability to ______a. make proteinsb. obtain fresh airc. produce inorganic nitrogend. carry out activities without energy65. according to the passage, what is atp?a. a biochemical process.b. the tip of a root.c. a chemical pound.d. a type of plant cell.66. the underlined word intact in paragraph 2 is closest in meaning to ______a. mature b.