Transpiration

Question 1

Vascular Pathway

Answer 1

Through vacuole

Question 2

Appoplast Pathway

Answer 2

Through cell wall and into cytoplasm at caspian strip. Forced through membrane so plant can control what enters xylem.

Question 3

Root Pressure

Answer 3

Mineral ions move into xylem by active transport. Lower water potential. Water moves in xylem. Water pushed up xylem but only a few metres.

Question 4

Mass flow

Answer 4

Movement of body of water from area of high pressure to area of low pressure.

Question 5

Cohesion

Answer 5

A force attracting same molecules together.

Question 6

Adhesion

Answer 6

A force attracting different molecule together.

Question 7

Photometer

Answer 7

Measures water uptake from a cut root (not really transpiration).

Question 8

Transpiration in leaves

Answer 8

Water moves out xylem (osmosis)
Into spongy mesophyll cells
Evaporates into air spaces
Vapour diffuses out through open stomata

Question 9

Factors that a affect transpiration…

Answer 9

• Number of leaves
• Number, size and position of stomata
• Cuticle thickness
• Light intensity
• Temperature
• Humidity
• Air movement

Question 10

Xerophytes

Answer 10

• Small leaves: less stomata and surface area
• Thick cuticle: less evaporation
• Hairs: trap vapour near stomata and lowers vapour potential gradient
• Sunken stomata: traps moist air
• Densely packed spongy mesophyll: lowers surface area

Question 11

Simplast Pathway

Answer 11

Through cytoplasm