Water

Question 1

Asymmetric shape of water molecules

Answer 1

Dipole

Question 2

What causes Surface tension?

Answer 2

Hydrogen bonding

Question 3

What happens to density and volume when water freezes?

Answer 3

Less dense, more volume

Question 4

Water’s ability to absorb a large amount of heat without much change in temp

Answer 4

High specific heat

Question 5

When soil pores are filled to the max with water

Answer 5

Saturated

Question 6

What effects water movement?

Answer 6

Gravity, adhesion, cohesion

Question 7

Capillary action

Answer 7

Adhesion and cohesion and moved water in any direction

Question 8

Capillary rise

Answer 8

Loss of water by evaporation

Question 9

Water potential

Answer 9

High to low

Question 10

Negative pressure

Answer 10

Tension or suction

Question 11

What does tension do to water potential

Answer 11

Lowers

Question 12

What is atm equal to?

Answer 12

.101 MPa

Question 13

What determines soil water potential?

Answer 13

Gravity, matric forces, osmotic forces

Question 14

What are matric forces

Answer 14

Adhesion and cohesion

Question 15

What are osmotic forces?

Answer 15

Dissolved salts

Question 16

What causes water to spread laterally when soil is moist

Answer 16

Matric potential

Question 17

What causes fertilizer burn?

Answer 17

High concentrations of salt creates osmotic potential that inhibits water uptake

Question 18

When soil is saturated, water tension is…

Answer 18

Zero until drainage, plant use, or evaporation

Question 19

When adhesive and cohesive forces are equal to gravity

Answer 19

Field capacity

Question 20

Permanent wilting point

Answer 20

Soil moisture content when a plant wilts and can’t recover even with optimal water conditions

Question 21

Soil texture determines relationship between…

Answer 21

Soil water content and soil moisture tension

Question 22

Hygroscopic water

Answer 22

Adsorbed water of thin, tightly bound layer surrounding soil particles. Moisture tension is too high

Question 23

Crystal lattice water

Answer 23

Less available to plants than hygroscopic water and can only be removed by sufficient heat

Question 24

Available water range

Answer 24

Soil moisture between field capacity and permanent wilting point

Question 25

Is water between saturated and field capacity available and why?

Answer 25

No because lost through drainage

Question 26

Is PWP the same for all plant species

Answer 26

No

Question 27

Is water closer to field capacity or PWP more available?

Answer 27

Field capacity

Question 28

What moves water up the stem

Answer 28

Cohesion and tension

Question 29

What carries minerals up a stem?

Answer 29

Xylem streams

Question 30

What is the movement of water from roots to stem to leaves to atmosphere

Answer 30

Transpiration stream

Question 31

What causes transpiration pull

Answer 31

Evaporation from outer surface of mesophyll cells

Question 32

Is osmosis used that often?

Answer 32

No it’s relatively small

Question 33

What moves minerals through impermeable membranes in roots

Answer 33

Active transport through energy from respiration

Question 34

Girdle

Answer 34

Phloem tissue is cut so below is starved while above is okay