Lesson 9 - Water and Glucose Transport in Plants

Question 1

What is the molecular bond in a molecule of water?

Answer 1

Two Hydrogen Atoms and One Oxygen Atom(H2O) - hydrogen bent around the oxygen

Question 2

Oxygen is slightly more electronegative causing it to have a STRONGER hold on the electron in the molecular bond in?

Answer 2

Water

Question 3

What makes the magnetic bond in water?

Answer 3

Oxygen being a slightly negative charge and the hydrogen having a slightly positive charge.

Question 4

Due to the polar nature of individual water molecules, multiple water molecules will experience an attraction to each other creating what?

Answer 4

Hydrogen bonds and forming long chains of water molecules

Question 5

What is the property of water molecules to be weakly attracted to each other called?

Answer 5

Cohesion

Question 6

When you do a belly flop off a diving board or why rain falls in droplets rather than a mist is explained by the property of ?

Answer 6

Cohesion

Question 7

What is the property called that causes water to experience an attractive force to certain types of surfaces?

Answer 7

Adhesion

Question 8

When water is attracted to the sides of xylem tubes in plants or a meniscus in a glass beaker it is called?

Answer 8

Adhesion

Question 9

What are the three mechanisms that help the plant bring water UPWARDS in the opposition to gravity?

Answer 9

Capillary Action
Root Pressure Push
Transpiration Pull

Question 10

The combination of COHESIVE forces between water molecules and ADHESIVE forces causing the water molecules to STICK to the edges of VERY THIN tubes may cause the water level to RISE within the tube (even opposed to gravity) - rise in water up to 10 metres

Answer 10

Capillary Action

Question 11

The roots of a plant are covered in a ONE thin layer of DERMAL tissue that forms root hairs, very small protrusions whose large SA/V ratio allows them to effectively PULL water from the soil into the roots by OSMOSIS. This water then moves INTO the xylem tubes (by OSMOSIS) increasing the tugor pressure inside the xylem cells in the roots and PUSHING water UP the xylem tubes. - rise in water up to 7 metres

Answer 11

Root Pressure Push

Question 12

What is the process when the stomata in the leaves are OPEN to allow CO2 into the spongy mesophyll layer and water vapour escapes from the leaves?

Answer 12

Transpiration

Question 13

When transpiration occurs, 99% of the water absorbed by their roots in trees is lost.
When the water is lost from the leaves, COHESIVE forces between the water molecules cause more water to be PULLED UPWARDS to replace that which was lost. What is this water transport called?

Answer 13

Transpiration PULL

Question 14

What tissue is used to transport glucose in a plant?

Answer 14

Phloem Tissue

Question 15

What is the theory described below?
Initially the sugars and other minerals are pumped in to the phloem tissue in the plant’s leaves using ACTIVE TRANSPORT. This high solute concentration causes water to flow into these cells creating turgon pressure which forces the sap like sugar solution DOWNWARDS. AS this phloem sap moves towards the roots, some of the solute is brought out of the phloem vessels to nourish surrounding tissues.

Answer 15

Pressure Flow Hypothesis

Question 16

What does phloem tissue consist of?

Answer 16

Thin hollow sieve tube elements (where glucose sap can flow)
Connected by Sieve Plates
Most phloem tissue is surrounded by companion cells who provide energy in the form of ATP, proteins and other resources to the cells within the phloem tissue