Transport in plat, xylem, phloem, transpiration, translocation, transpiration, vascular bundle

1. INTERNATIONAL ACADEMY - AMMAN
GRADE 9 / MYP 4 / BIOLOGY / Transport in plants
NAME: ................................... DATE: /1/2016
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Transport in plant:
Two types of transport tissues in plants:
1-Xylem: dead cells which is used to transport of water and dissolved mineral ions and salt from
root to the stem then leaves
2-Phloem: living cell which is used to transport food substance (glucose and amino acids) from
leaves to the other plant parts including roots
C.S in plant root
Cortex: highly permeable to the water and it store water within the vacuole.
Endodermis: inner layer of root and it is surrounded by a vascular bundle.
Endodermis made of wax so it ac as a waterproof.

2. C.S in plant stem
Cortex cell:
- Store starch. - It contains chlorophyll pigment.
Pith: central tissue cells.
(Cortex+Pith) are involved in the process of packing and support for the plant.
Explain how root is adapted to uptake (absorb) water from soil:
- It consists of thin layer of cells for fast diffusion
- They are large in number to provide more surface area to absorb water from soil
- It has fine hair cell to absorb water from soil particles by osmosis.
State the pathway taken by water through root, stem and leaves:
1- Root hair will absorb water from soil particles by osmosis.
2- Water will pass the cortex cell (highly permeable to water) in root
3- Water will pass to the xylem in root then stem till it reaches the xylem of leaves to be used by
cells (palisade and spongy cell) for photosynthesis.

3. Investigation: xylem to transport water and dissolved ions and salts
- Add stain (blue) to the water, then insert small branch of certain plants,
- Leave the plant for several hours.
- Prepare slide from root, stem and leaves
- Observe the place of stain
Result: the blue stain was found inside the xylem
Conclusion: xylem is used to transport water.
** Name one stain which is used to show that the xylem is responsible for transporting water and
dissolved mineral ions and salt.
Eosin stain (red stain)
Translocation:
- Long distance transport (mass flow system)
- Movement of sucrose and amino acids from leaves (where is produced by photosynthesis) to
the root (sink) to be stored and used in respiration or growth.
Transpiration:
Evaporation of water at the surface of mesophyll cells followed by loss of water vapour from plant
leaves through the stomata.
Two types of transpiration:
1- Transpiration from the epidermis (less).
2- Transpiration from the stomata (more):
* Water will move by osmosis from xylem to the mesophyll cell
* Excess water will be evaporated in the spaces between spongy cell and leave stomata in
form of water vapour.
Water will be transported in xylem up to reach leaves by:
- Transpiration which make pulling forces
- Water potential gradient in xylem which draw cohesive water molecules up the plat
- High root pressure at the bottom of the plant

4. Comparing transpiration and translocation:
Discuss the adaptations of the leaf, stem and root to the pond, garden and desert (according to
the temperature, light intensity and humidity).
1- Desert plants adaptation:
- Small leaves: has small surface area to reduce water loss (transpiration).
- Has hair cell to trap humidity to decrease loss of water (transpiration).
- Thick cuticle in leaves to reduce loss of water (transpiration).
- Long root to go down deep in soil to absorb water.
2- Pond plants adaptation:
- Reduce root system because it is sink in water.
- Dissected lamina leaves to protect it.
- Leaves have air space for floating.
- No stomata.

5. Explain factors affecting the rate of transpiration:
1- Temperature:
- As temperature increase the transpiration rate increase
- At high temperature: more rate of transpiration and the plant get wilting.
2- Light intensity:
- In bright light there will be more rate of transpiration.
- In dim light: less rate of transpiration.
3- Wind:
When the speed of wind increase the rate of transpiration will increase, because wind will remove
evaporated water which surround the surface of the leaf to increase the transpiration rate.
4- Humidity:
When the humidity increase the transpiration rate will decrease.
Translocation:
Movement of sucrose and amino acids in phloem from region of production (leaves) to region of
storage or utilisation in respiration and growth.
Application on translocation:
Systemic pesticides:
- Are pesticides which are absorbed by plants or animals and move to untreated tissues.
- The pesticides translocated to kill weeds and pest as it begins to feed or enter the plant
- Water and food-conducting tissues are the usual pathways through which these chemicals
move over long distances

6. Explain factors affecting the rate of transpiration:
1- Temperature:
- As temperature increase the transpiration rate increase
- At high temperature: more rate of transpiration and the plant get wilting.
2- Light intensity:
- In bright light there will be more rate of transpiration.
- In dim light: less rate of transpiration.
3- Wind:
When the speed of wind increase the rate of transpiration will increase, because wind will remove
evaporated water which surround the surface of the leaf to increase the transpiration rate.
4- Humidity:
When the humidity increase the transpiration rate will decrease.
Translocation:
Movement of sucrose and amino acids in phloem from region of production (leaves) to region of
storage or utilisation in respiration and growth.
Application on translocation:
Systemic pesticides:
- Are pesticides which are absorbed by plants or animals and move to untreated tissues.
- The pesticides translocated to kill weeds and pest as it begins to feed or enter the plant
- Water and food-conducting tissues are the usual pathways through which these chemicals
move over long distances