Franklin Pierce University PA 210 QUIZ 7 TRUE/FALSE QUESTIONS 1 TO 4 1)The element potassium helps plants adapt to environmental stresses   Calcium is critical to plant root growth    90 – 98% of soil K is readily available ions soluble in water or in exchangeable form on soil colloid surfaces    PO4 ions are fixed by oxides of Al and Fe in alkaline soils   The element___________ is found in ATP, DNA, RNA, and cellular membranes of plants   _________ plant-available soil S comes from microbial decomposition of organic matter   Sulfate is leached from the soil unless there is ____________exchange capacity   The plant nutrient ____________ comes from weathering of carbonate minerals and liming materials   Metal micronutrients form organo-metallic complexes called____________   _________is the most commonly deficient micronutrient, is more available under acid conditions, and is adsorbed by humus