Outline the process by which water enters the cells of the root from the soil.?

Question

I think this is Osmosis or is it? i'm not entirely sure..

Thanks

Answer 1

Yes it is the process called osmosis.
The osmosis is the capacity of water to entry against the gravital law,into a plant throw it's limfatic vassels.The roots contain cells with certain organits called leucoplastides,wich contain starch,and have the role of absorbing the nutrients in the water and store them or transport them in the cells of the plant.

Answer 2

Osmosis is the method if the concentration of water in the soil is MORE than that of the plant. If it is the otherwise, the plant would use Transpiration Pull to "pull" the water up the roots. It requires energy to go against this concentration gradient.

Answer 3

"when two liquids of different concentration are separated by a semipermiable membrane,the liquid with lesser concentration enters the liquid with a higher concentration.This is OSMOSIS."
when freshly watered,the water in the soil is less concentrated with soil when compared to the cytoplasm of the cells in roots of the plant.so the water enteres the roots by the process of osmosis where the plasma membrane(infact every cell membrane acts as a semipermiable membrane).when water enters the cells, the concentration of cytoplasm of that cells is decreased and the next cell undergoes osmosis with this cell.thus water enters the roots of the plants.

Answer 4

Osmosis is the mind-set if the concentration of water interior the soil is larger than that of the plant. if it truly is the otherwise, the plant may use Transpiration Pull to "pull" the water up the roots. It demands ability to evade compared concentration gradient.

Answer 5

Absorption of water and minerals by roots: Water and mineral enter through root epidermis, cross the cortex, pass into the stele, and are carried upward in the xylem.
Active accumulation of Mineral Ions. The cells cannot get enough mineral ions from the soil by diffusion alone. The soils solution is too dilute.
ACTIVE TRANSPORT of these ions must occur. Specific carrier proteins in the plasma membrane attract and carry their specific mineral into the cell. A Proton Pump: H+ is pumped out of the cell causing a change in pH and a voltage across the membrane. This helps drive the anions and cations into the cell. Water and minerals cross the cortex in one of 2 ways: Via SYMPLAST which is the living continuum of cytoplasm connected by PLASMODESMATA. Via APOPLAST which is nonliving matrix of cell walls. At the endodermis the apoplastic route is blocked by the CASPARIAN STRIP. this is a ring of suberin around each endodermal cell. Here water and minerals MUST enter the stele through the cells of the endodermis. Water and minerals enter the stele via symplast, but xylem is part of the apoplast. Transfer cells selectively pump ions out of the symplast into the apoplast so they may enter the xylem. This action requires energy.

ASCENT of XYLEM SAP:
Water transported up from the roots must replace water lost by transpiration.

WATER POTENTIAL: Xylem sap rises against gravity, driven by a gradient of water potential (*) Water flows from an area of high * to an area of low *. Water Potential is expressed in units of pressure: 1 bar = pressure needed to push a column of water up 10 meters. 1 megapascal= 10 bars. Pure water has * = 0. Addition of pressure increases *. Addition of solutes decreases *.
ROOT PRESSURE: When transpiration is low, ions pumped into the stele decrease * and cause water uptake by the stele. This uptake force is called root pressure. Cannot keep pace with transpiration, can force water up only a few meters.

TRANSPIRATION-COHESION-ADHESION THEORY:
a). water leaves leaf through stomata.
b). this water loss is replaced by evaporation from mesophyll cells, lowering their water potential, causing them to take water from neighboring cells.
c). Process continues back to the tracheids causing water up take from the xylem sap.
d). Water goes fro tracheids to air following a water potential gradient.
e). Cohesion and adhesion of water. H bonds of water, hydrophilic walls of xylem and small diameter of xylem aid in the movement of water up the tube.
f). This pull decreases water pressure in the xylem causing the roots to take water from the soil.

How Stomata Open and Close:
Turgid guard cells open the stomata, while flaccid cells close them.
The K+ ion is responsible for the stomatal action.
Uptake of K+ causes the cell to become turgid- decreases water potential.
Stomata open at dawn because light induces the cells to take in K+. An internal clock (circadian rhythm) will make them open even if in they are kept in the dark.
Guard cells will close due to: a water deficiency, High temperatures due to an increase of CO2