Meristematic tissues and growth 1.2 Flashcards
(34 cards)
Where apical meristem tissues are located?
Located at the tip of plant shoots and roots
What does the lateral meristem tissues consists of?
Vascular cambium and cork cambium.
Name the 3 different zones in the zone of cell growth in the order of stages.
Zone of cell division, zone of cell elongation, zone of cell differentiation.
Name the growth of apical meristem.
Primary growth.
Where does zone of cell growth occur?
Apical meristematic tissues (at the shoot and root tip of plants)
What happens in the zone of cell division?
Meristem cells undergo mitosis, the increase of cells causes elongation of the plant root/stem. The cells that are formed previously is pushed to the zone of cell elongation.
State the characteristics of the cell in zone of cell division.
Have small vacuole, nucleus (draw big) and cytoplasm.
What happens in the zone of cell elongation?
Cells are increasing in size that happens because of water diffusion by osmosis and absorption of nutrients in the cells and is stored in the vacuole. The diffused water exerts pressure against the cell wall which elongates and widens the cell. Vacuolation happens.
State the process of vacuolation.
Small vacuole fuse together to form a large vacuole.
State the characteristics of the cell in zone of cell elongation.
Have large vacuole, nucleus (draw smaller than vacuole), cytoplasm.
What happens in the zone of cell differentiation?
Cell that have reached their maximum size will differentiate to form permanent tissues such as phloem, xylem, epidermis, cortex. These specialised cells have specific functions.
Example of the function of cells that have undergone differentiation. eg: root hair cells.
Example, epidermal cells in leaves differentiate and form guard cells that controls the opening of stomata.
Name 2 types of growth in plants.
Primary and secondary growth.
What is primary growth?
The growth that occurs after germination and takes place in all plants.
Where does primary growth takes place?
In apical meristems.
In the shoot tips, what will the leaf primordia and shoot primordia will grow into?
They will form new leaves and shoots.
When the root cap is exhausted, how can it be replaced?
The cell can be replaced by the meristem cells.
What is secondary growth?
This growth increases the circumference of plant stem and root. It occurs mainly in eudicots and small number of monocots only.
Which plants will not undergo secondary growth?
Herbaceous plants.
How does the secondary growth occur?
From the division of lateral meristem cells located in stem and root. Lateral meristem consists of vascular and cork cambium.
Where does the vascular cambium located at?
Between xylem and phloem tissues in vascular bundles.
Where does the cork cambium located at?
Under the epidermal layer.
State the process of secondary growth at the plant stem.
Vascular cambium divides actively through mitosis and become cambium ring. Then cambium ring cells divide inwards to form new xylem and phloem which is the secondary xylem and secondary phloem. During this time, primary xylem is pushed towards the pith, while primary phloem is pushed towards the epidermis. The primary xylem is compressed to form a stronger wood layer because the walls of xylem is thickened with lignin that provides mechanical support to plants.
In secondary growth of plant stem, what did the cork cambium actively divides into?
They form cork cells (outer side) and cortex (inner side).
