Transportation

Question 1

Transpiration

Answer 1

The loss of water vapour from a leaf is called transpiration.
It ‘pulls’ water up the xylem from the roots.
The evapouration of water from the surface of a plant.

Question 2

Xylem

Answer 2

Transport tissue in plants which carries water and mineral ions up from the root through the stems to the leaves

Question 3

Phloem

Answer 3

Tissue that transports sugars or energy and amino acids for cell building all around the plant.

Question 4

Definition of:

diffusion

Answer 4

happens when a substance is more concentrated in one place than another. (eg CO2)
CO2 molecules will gradually move to an area of lower concentration.

Question 5

Definition of:

Osmosis

Answer 5

water moving across cell membranes. Water will move to more concentrated are to dilute it. (still moving from high concentration of water molecules to lower concentration)

Question 6

Definition of:

Active Transport

Answer 6

Happens when cell needs a substance of low concentration outside of cell. (Against a concentration gradient). Here, they use energy from respiration to take up particles.

Question 7

How is water absorbed by root hair cells?

Answer 7

The hairs increase the surface area. Each hair is specialised cell of the epidermis. The hairs penetrate between the soil particles reaching the water. The water enters the root hair cells by osmosis. It then moves into the outer tissue of the root.

Question 8

Factors that affect transpiration and how

Answer 8

Light Intensity: rate of transpiration increases in the light because the stomata in the leaves open.
Temperature: high temperature=more transpiration because the rate of evapouration increases
Humidity: decreases in humid air, increases in dry hair
wind speed: rate of transpiration increases with faster air movements because it removes water vapour near stomata

Question 9

Experiment to show diffusion

Answer 9

Demonstration of diffusion in jelly:
Use agar jelly
prepare a petri dish, which contains a 2cm deep layer of jelly, dyed purple with potassium permanganate solution.
three cubes of different sizes are cut out of the jelly with side lengths of 2cm, 1cm, and 0.5cm
drop cubes at the same time into beaker of dilute HCl
the time is taken for each cube to turn colourless
repeat

Question 10

Experiment to determine rate of respiration

Answer 10

Potometer

Measures the rate of loss of mass from a potted plant or leafy shoot over a period of time.