Page 12 - E-Biology Sec.2 2024-2025 U1_Handy

b) Absorption of mineral salts:

The plant needs other essential elements besides C, H, O and their shortage leads to:

o Disturbance or stop in the plant vegetative growth.

o Nonproducing of flowers / fruits.

P.O.C Macro-nutrients Micro-nutrients (Trace elements)

Definition They are needed in considerable They’re needed in v. small

quantities. quantities (not exceed few mg/L)

Number 7 elements (N, P, K, Ca, Mg, S, Fe) 8 (Mn, Zn, Al, B, Cl, Cu, Mo, I)

Importance (NO3)-, (PO4)-3, (SO4)-2 convert Some work as activators of
coenzymes.
carbohydrates proteins.

P enters in the composition of energy

carrier compounds. “ATP, ADP”

Fe is for building some coenzymes that

are required for accomp. Photosynthesis.

Mg is for chlorophyll synthesis.

1. Diffusion
phenomenon

Element’s ions (solutes) diffuse independently in the form of:

(Cations K+, Ca+2 / Anions (NO3)-, (NO2)-, (SO4)-2, (Cl)-)

Solutes diffuse from the soil sol. high conc. med. Wet cellulose wall low conc. med.
due to the continuous movement of free ions.

Cation exchange may occur through the cell membrane as Na+ can be replaced by K+.

12

First Term