Plants need phosphorus to build nucleic acids, phospholiqids, and ATP Potassium ions activate many of the enzymes essential for photosynthesis and respiration Plants also utilize calcium, magnesium, and sulfur Calcium ions are essential for building cell walls Magnesium ions are essential for the formation of chlorophy ll Cluster of phyll b pigment molecules CH, in chlorophy 一GH-cH Granum (stack of thylakoids) hurin ring Thylakoid drocarbon tail (H atoms not shown) CopytigHt O Pearson Education, ine, pushing as Berkman Cumming
• Plants need phosphorus to build nucleic acids, phospholiqids, and ATP. • Potassium ions activate many of the enzymes essential for photosynthesis and respiration. • Plants also utilize calcium, magnesium, and sulfur • Calcium ions are essential for building cell walls. • Magnesium ions are essential for the formation of chlorophyll
15.3 Soil fertility is determined by soil structure and nutrient retention Topsoil usually contains sand. silt a Soil Layers and clay 口0 Horizon( humus) Fertile topsoil is a A Horizon (topsoil) mixture of at least E Horizon(eluviation layer) four components 0°°:1 B Horizon( ( subsoil mineral particles water, aIr, organIc C Horizon (regolith matter R Horizon(bedrock
15.3 Soil fertility is determined by soil structure and nutrient retention • Topsoil usually contains sand, silt, and clay. • Fertile topsoil is a mixture of at least four components: mineral particles, water, air, organic matter