Transport in Plants

Question 1

Root cap

Answer 1

The root cap is a type of tissue at the tip of a plant root.

Question 2

Transpiration

Answer 2

Loss of water from plant leaves by evaporation at the surfaces of the mesophyll cells followed by loss of water vapour through the stomata

Question 3

Water potential

Answer 3

transpiration is the difference in water potential between the soil and the atmosphere surrounding the plant. This difference creates a gradient, forcing water to move toward areas with less water. These resistances slow water movement.

Question 4

How temperature effects transpiration

Answer 4

As temperature increase, transpiration increases since more water is evaporated

Question 5

How humidity effects transpiration

Answer 5

The higher the humidity the less water will evaporate since there is less of a gradient for the water between the air spaces inside the leaf.

Question 6

Wind speed

Answer 6

Transpiration increases as wind speed increases

Question 7

Light intensity

Answer 7

As Light intensity increases, the amount of transpiration increases, as more carbon dioxide is taken into the plant through the stomata

Question 8

Water supply

Answer 8

The lower the water supply, the plant will close its stomata so the rate of transpiration decreases

Question 9

Flaccid

Answer 9

drooping or inelastic through lack of water.

Question 10

Translocation

Answer 10

The movement of sucrose and amino acids in phloem, from regions of production (sources) to regions of storage or growth (sink).

Question 11

Xylem

Answer 11

It is like along drain pipe made of many hollow, dead cells joined end to end. It has no ends and it runs from the roots of the plant right up through the stem and branch out to every leaf. They are made from cellulose and lignin

Question 12

Vascular bundles

Answer 12

A group of phloem tubes and xylem vessels is called a vascular bundle. They are located in the centre of the root and near an outside edge in a shoot.

Question 13

Transpiration stream

Answer 13

Water drawn from the leaf xylem is in turn replaced by the water that flows upwards from the stem xylem, and this is replaced by the water from root xylem which is replaced by the water drawn from the root hairs.

Question 14

Structure of a plant to help water absorption

Answer 14

• The root hair increases surface area so more water can be absorbed
• Xylem vessel is narrow and hollow which provides an easy path for water to flow
• The many air spaces in the leaf means that large surface area of wet cells for water to evaporate into.
• The stomata opens to allow water vapour to diffuse easily out of the leaf.