TRANSPORT IN PLANTS
What is the name of the transport tissue in plants?
The vascular tissue
What are the two types of vascular tissue?
The phloem and Xylem tissue
What are herbaceous plants?
Plants that have stems which are soft and non woody.
Why do plants need a transport system?
Because transport distances are usually long and the surface area to volume
ratio is small thus, they cannot rely on diffusion.
Describe the structures that are common in the stem and roots.
The outermost layer is the epidermis, most of the stem and root contains living
undifferentiated cells known as parenchyma cells.
Describe the distribution of the vascular tissue any dicotyledonous
stem.
The vascular tissue is arranged towards the outside of the stem.
Why is the distribution of the vascular tissue in a dicotyledonous
stem so?
The main forces acting on the stem are lateral forces caused by the action of
wind and such forces are best resisted by an outer cylinder of supporting tissue.
What is the arrangement of the Xylem and the phloem in the
vascular tissue?
The Xylem is on the inside whilst the phloem is on the outside.
Describe the distribution of vascular tissue in a dicotyledonous root.
The vascular tissue is situated in the centre of the root.
Why is the distribution of vascular tissue in a root so?
Roots are subjected to only pulling forces and vertical forces are better resisted
by a central column of supporting tissue.
What are root hair cells?
They are modified epidermal cells that have large vacuoles and cytoplasmic
extensions projecting into the soil.
What is the difference between the uptake of water and the uptake
of mineral ions?
, Water is taken up by osmosis however mineral ions are taken up actively.
What other structural adaptations of root hair cells other than their
long tails?
No waxy cuticle and a thin cellulose cell wall
Many aquaporins
Many mitochondria to provide ATP for active uptake.
Describe the structure of a leaf.
It has an epidermis composed of colourless cells which allows light to enter the
leaf.
It has a waxy cuticle to minimise water loss.
What is the main tissue that carries out photosynthesis?
The palisade mesophyll
what are the different cells of the Xylem tissue?
Xylem vessel elements
Xylem tracheid
Xylem parenchyma
what is the structure of the Xylem vessel elements?
Hollow and elongated because as they grow, they become impregnated with
lignin.
How is the Xylem vessel formed?
The Xylem vessel elements become impregnated with lignin as they mature,
and this causes them to die as this happens their end walls break off and they
join to form a continuous tube.
Why does lignin thicken the vessel elements in a spiral, Annular, and
reticulate manner instead of continuously?
This arrangement allows the elongation of the vessels as the plant grows.
What are the names of non-lignified regions in the Xylem vessel
elements?
Pits
What is the use of the pits?
They allow the lateral movement of water.
What is the name of the transport tissue in plants?
The vascular tissue
What are the two types of vascular tissue?
The phloem and Xylem tissue
What are herbaceous plants?
Plants that have stems which are soft and non woody.
Why do plants need a transport system?
Because transport distances are usually long and the surface area to volume
ratio is small thus, they cannot rely on diffusion.
Describe the structures that are common in the stem and roots.
The outermost layer is the epidermis, most of the stem and root contains living
undifferentiated cells known as parenchyma cells.
Describe the distribution of the vascular tissue any dicotyledonous
stem.
The vascular tissue is arranged towards the outside of the stem.
Why is the distribution of the vascular tissue in a dicotyledonous
stem so?
The main forces acting on the stem are lateral forces caused by the action of
wind and such forces are best resisted by an outer cylinder of supporting tissue.
What is the arrangement of the Xylem and the phloem in the
vascular tissue?
The Xylem is on the inside whilst the phloem is on the outside.
Describe the distribution of vascular tissue in a dicotyledonous root.
The vascular tissue is situated in the centre of the root.
Why is the distribution of vascular tissue in a root so?
Roots are subjected to only pulling forces and vertical forces are better resisted
by a central column of supporting tissue.
What are root hair cells?
They are modified epidermal cells that have large vacuoles and cytoplasmic
extensions projecting into the soil.
What is the difference between the uptake of water and the uptake
of mineral ions?
, Water is taken up by osmosis however mineral ions are taken up actively.
What other structural adaptations of root hair cells other than their
long tails?
No waxy cuticle and a thin cellulose cell wall
Many aquaporins
Many mitochondria to provide ATP for active uptake.
Describe the structure of a leaf.
It has an epidermis composed of colourless cells which allows light to enter the
leaf.
It has a waxy cuticle to minimise water loss.
What is the main tissue that carries out photosynthesis?
The palisade mesophyll
what are the different cells of the Xylem tissue?
Xylem vessel elements
Xylem tracheid
Xylem parenchyma
what is the structure of the Xylem vessel elements?
Hollow and elongated because as they grow, they become impregnated with
lignin.
How is the Xylem vessel formed?
The Xylem vessel elements become impregnated with lignin as they mature,
and this causes them to die as this happens their end walls break off and they
join to form a continuous tube.
Why does lignin thicken the vessel elements in a spiral, Annular, and
reticulate manner instead of continuously?
This arrangement allows the elongation of the vessels as the plant grows.
What are the names of non-lignified regions in the Xylem vessel
elements?
Pits
What is the use of the pits?
They allow the lateral movement of water.
