Transport In Plants

Question 1

How many transport systems does a plant have

Answer 1

They have 2 systems, the xylem and phloem

Question 2

What does the xylem tissue do

Answer 2

Transports water and minerals ions from the roots to the leaves, stem and flowers

Question 3

What does the phloem tissue do

Answer 3

The phloem tissue transports dissolved sugars produced during photosynthesis, and other soluble food molecules from the leaves to all of the other areas of the plant

Question 4

What are meristems

Answer 4

The place where new plant cells are made

Question 5

What is the process of moving sugars around the plant through the phloem called

Answer 5

Translocation

Question 6

What is the structure of the xylem

Answer 6

• the xylem vessels are made form dead xylem cells
• they form tubes which run through the plant stems
• there are no cell walls at the end of these cells,

Question 7

What is the structure of the phloem

Answer 7

• Phloem vessels are made of living cells
• the walls of the cells do not completely break down
• sieve plates are formed (they are small holes in the end wall which allow the dissolved sugars to pass through)
• the connection of phloem stems forms a tube which allows dissolved sugars to be transported

Question 8

How do the vascular bundles provide support

Answer 8

• in the leaf they form a network that supports the softer leaf tissue
• I’m the stem they are located around the outer edge, providing the stem with strength to resist bending in the wind
• in the root they are found in its centre, enabling the to act as an anchor - the root can bend as the plant moves in the wind

Question 9

How does the evaporation of water from the leaves work

Answer 9

The water molecules are taken up from the roots to the leaves by the xylem cells.

• as the water molecules travel up into the leaves, the guard cells become turgid, and the stomata open
• the water flows out of the leaf through the stomata, due to the concentration gradient
• inside the leaf, there is a high concentration of water, but outside in the air, there is a low concentration
• while the stomata are open, CO2 is then able to flow into the leaf, which is used to fuel photosynthesis

Question 10

Transpiration stream definition

Answer 10

The chain of water molecules that travel up the Xylem cells

Question 11

Transpiration meaning

Answer 11

The evaporation of water from the leaves

Question 12

What factors effect the rate of transpiration

Answer 12

• humidity
• light intensity
• temperature
• air flow

Question 13

How does light intensity effect rate of transpiration

Answer 13

Brighter light means that more photosynthesis will occur, meaning that more carbon is needed. This means that more water will have to evaporate, meaning a higher rate of transpiration

Question 14

How does temperature affect the of transpiration

Answer 14

The warmer it is, the higher the rate of transpiration

• the water particles will have ore energy, so they will be more likely to evaporate and diffuse out of the stomata

Question 15

How does wind speed effect transpiration

Answer 15

The rate of transpiration increases and decreases depending on if the wind speed is increased or decreased

• if the airflow is high, water particles in the the outside of the leaf will be blown away quicker. This means that there will be rapid changes in the concentration gradient.
  —> the reason the concentration gradient is larger, is because as the water is b,own away there will be more water inside that outside of the leaf

Question 16

How does humidity effect rate of transpiration

Answer 16

Humidity is the measure the rate of how much water is in the air at a given time

If there is a lot of water in the air, the concentration gradient will be low, meaning that transpiration will happen slowly,
If there is low humidity, there will be a high concentration gradient, which means that transpiration will go happen quicker