The water and minerals is transported by xylem  in the plants. the process of transpiration also plays a major role in the tranportation of water and mineral.

Xylem vessels and tracheids of the roots, stems and leaves are interconnected to form a continuous system of water-conducting channels reaching all parts of the plant.
At the roots, cells in contact
with the soil actively take up ions. This creates a difference in the concentration of these ions between the root and the soil. Water, therefore, moves into the root from the soil to eliminate this difference. There is steady movement of water into root xylem, creating a column of water that is steadily pushed upwards. 

To get rid of excretory products plants use the following ways:
(i) Excess water is lost by Transpiration.
(ii) Many plants waste products are stored in vacuoles of the cells.
(ii) Some waste products are stored in the leaves. They are removed as the leaves fall off.
(iii) Some waste products such as resins and gums are stored, especially in nonfunctional old xylem.
(iv) Some waste products such as tanins, resins, gums are stored in bark, thereby removed as the peeled off.
(v) Plants also excrete some waste substances through roots into the soil around them.
(vi) Oxygen is lost while the stomata opens for taking in carbon-dioxide.

Structure of Nephron: Nephron is the Alteration unit of kidney. It consists of a tubule which is connected with collecting duct at one end and a cup shaped structure at the other end.

This cup-shaped structure is called Bowman’s capsule. Every Bowman’s capsule contains a cluster of capillaries, called Glomerulus, with in the cup-shaped structure. The blood enters into glomerulus through Afferent arteriole of renal artery and leaves it through efferent arteriole.


Fig. Structure of nephron

(i) Functioning of nephron: Filtration of blood takes in Bowman’s capsule from the capillaries of glomerulus. The filterate passes into the tubular part of the nephron. This filterate contains glucose, amino acids, urea, uric acid, salts and a major amount of water.
(ii) Reabsorption: As the filterate flows along the tubule useful substances such as glucose, amino acids, salts and water are selectively reabsorbed into the blood by capillaries surrounding the nephron tubule.
The amount of water reabsorbed depends on the need of the body and also on the amount of wastes to be excreted.
(iii) Urine. The filterate which remained after reabsorption is called urine. Urine contain dissolved nitrogenous waste i.e., urea and uric acid, excess salts and water. Urine is collected from nephrons by the collecting dust to carry it to the ureter.

The transport system in highly organised plants consists of two components:
(i) Xylem: Consists of vessels, tracheids and other xylem tissues. The interconnected vessels and tracheids form a continuous system of water conducting channels reaching all parts of the plant. Xylem conducts water and dissolved minerals absorbed from the soil.
(ii) Phloem: Consists sieve tubes and companion cell which conduct soluble products of photosynthesis from leaves to different parts of the plant body. This transportation of prepared food material through pholem is called translocation.

In plants the water is transported through the xylem tissue system. The xylem tissue, vessels and tracheids of the roots stems and leaves are interconnected to form a continuous system of water-conducting channels that transports water to all parts of the plant. The water and minerals are taken up from the soil by the roots. The uptake of ions at the roots creates a difference in the concentration of these ions between the root and the soil. Thus, water moves into the root from the soil to eliminate this difference. This ensures that there is a steady movement of water into root xylem, creating a continuous column of water. The root pressure is not enough to transport the water to the high parts of the plant. The transpiration from the leaves creates a Transpiration Pull, which helps in the absorption and upward movement of water and minerals dissolved in it from roots to the leaves and ensure water and minerals transport even to the highest part of the plant.