Transport of Water In Plants

Question 1

Transport of Water In Plants

Answer 1

Water and minerals enter root hair vias osmosis, water moves towards center of root via Apoplastic or symplastic movement

Once water reaches endodermis, can only enter vascular cylinder through symplast pathways (apoplast pathways is blocked by casparian strips)

Question 2

Apoplastic Movement

Answer 2

Water moves through cell walls

Never actually enters the cell, only in the non-living portions

Question 3

Symplastic Movement

Answer 3

Water moves through one cell to the other

Moves from one cytoplasm to the next via plasmodesmata

Question 4

Movement of MInerals

Answer 4

Minerals are selective for by endodermins (K can enter, Na can’t)

Question 5

Osmosis in Plants

Answer 5

Osmotic gradient between soil and inside of root

Water moving from root into xylem (leaves behind buildup of minerals that can’t pass)

Question 6

Root Pressure

Answer 6

Water moving into root helps push water up the xylem

Minimal pressure compared to other forces involved in water movement

Responsible for guttation (build up of water droplets on plants)

Question 7

Capillary action

Answer 7

Due to adhesive properties of water and capillary tube

Water forms a continuos column up the xylem without a meniscus (indicates that effect of capillary action is also minimal)

Question 8

Cohesion-Tension Theory

Answer 8

Transpiration

Cohesion

Bulk Flow

Question 9

Transpiration

Answer 9

Water evaporated from leaves of plants, causes negative pressure in the leaves

Question 10

Cohesion

Answer 10

Water is cohesive, cuasing it to act like a single polymer unit as it moves up the xylem

Question 11

Bulk Flow

Answer 11

Bulk flow of water through plant caused by water evaporating from leaf surface, pulling water behind it

Transpiration is caused by heating action of the sun (driving force fro ascent of sap through plants)