Which of the following pair is correct?

Step-by-step solution

Plant absorbs calcium from the soil in the form of calcium ions (Ca 2+ ). Calcium is required by meristematic and differentiating tissues. During cell division, it is used in the synthesis of the cell wall, particularly as calcium pectate in the middle lamella. It is also needed during the formation of the mitotic spindle. It accumulates in older leaves. It is involved in the normal functioning of the cell membranes. It activates certain enzymes and plays an important role in regulating metabolic activities.