Uptake of minerals

• what is the soil water like in terms of dilution compared to the contents of the root hair cells?

  the soil water is a much more dilute solution than the contents of the root hair cells
• what is the soil water like in terms of minerals?

  minerals are present in very low concentrations
• how are minerals absorbed into the cytoplasm from the soil?

  by active transport, against a concentration gradient
• at what point do mineral ions stop moving along the apoplast pathways, in solution?

  until they reach the endodermis, the casparian strips prevents further movement in the cell walls
• how do mineral ions enter the cytoplasm after reaching the casparian strip?

  they enter by active transport and then diffuse or are actively transported into the xylem
• how does nitrogen enter the plant?

  it usually enters the plant as nitrate or ammonium ions, which diffuse down a concentration gradient in the apoplast pathway, but enter the symplast by active transport against a concentration gradient and then flow in the cytoplasm through plasmodesmata
• what does active transport allow for the plant?

  it allows the plant to absorb the ions selectively at the endodermis
• why is oxygen essential for roots?

  as it allows cells to produce ATP in aerobic respiration, which provides energy for active transport