Lecture 7

Question 1

water movement in large pore soil (sandy)

Answer 1

gravitational pull

Question 2

water movement in small pore space (clayey)

Answer 2

capillary action

Question 3

soil saturation is:

Answer 3

all pores are full of water, gravitational water is lost

Question 4

field capacity is:

Answer 4

available water for plant growth

Question 5

wilting point is:

Answer 5

no more water available for plants

Question 6

hydrotropic root growth is:

Answer 6

growth or roots towards water

Question 7

what does the casparian strip do?

Answer 7

forces water to cross a plasma membrane - made of lignin

Question 8

what is the suberin

Answer 8

a biopolymer found in the endodermis that helps with water holding

Question 9

what is the role of suberized endodermis in the roots?

Answer 9

decrease water permeability

Question 10

in radial conductance, water flows from:

Answer 10

soil to stele

Question 11

in axial conductance, water flows:

Answer 11

through the xylem

Question 12

radial conductance affected by;

Answer 12

anatomy, morphology, cell wall permeability, activity of water channels, etc.

Question 13

axial conductance affected by;

Answer 13

number, diameter and structure of xylem conduits.