Primary Structures Flashcards
What is growth in plants?
Irreversible increase of dry mass associated with the development of an organism
What type of growth do plants exhibit throughout their life?
Indeterminate growth
What are the primary structures of a dicot root?
Root hair, epidermis, cortex, endodermis, pericycle, xylem, phloem
What is the function of root hairs?
Absorption of water and minerals
What is the innermost single cell layer of the cortex in plant roots?
Endodermis
What is the outermost cell layer of a root?
Epidermis
What is the role of the cortex in plant roots?
Stores carbohydrates and transports water and minerals
What is the Casparian strip?
A suberin belt in the endodermis with no inter-cellular spaces, that blocks cortical apoplast from vascular apoplast
What is the pericycle?
A layer containing 2 or 3 parenchyma cell layers with meristematic function located interior to the endodermis
Fill in the blank: The _______ is responsible for the formation of lateral roots.
Pericycle
True or False: The primary structure of monocot roots is significantly different from dicot roots.
False
What type of cells mainly make up the cortex?
Parenchyma cells
What are the two main tissues found in the vascular cylinder of roots?
Xylem and phloem
What is the primary function of the epidermis in roots?
Protects inner parts of the root
What is the composition of the cortex in plant roots?
Mostly parenchyma cells with intercellular spaces
Fill in the blank: The _______ contains no inter-cellular spaces.
Endodermis
What is the role of parenchyma cells in the pericycle?
Involves in lateral root formation and secondary growth of the root
What is the difference between primary structures of monocot and dicot roots
Distribution pattern of xylem and phloem tissue
What is present inner to the pericycle in the roots
Vascular tissue as a solid core
What surrounds the vascular tissue in monocot roots?
A ring if alternating xylem and phloem
Is the pericycle in monocot roots meristemstic
No
What is found in the central core of vascular tissue in monocot roots?
Parenchyma cells
Describe the shape of the xylem tissue in a cross section of a dicot root.
Star shaped
This is in contrast to the circular arrangement in monocots.
Where is phloem located in dicot root
In the grooves between the arms of xylem
What can be found in the middle of solid core of vascular tissues in dicot roots?
Xylem
What is the outer most layer in primary structure of dicot stem
Epidermal cell layer
Function of epidermal cell layer
Protects inner parts from dessication and infections
What are the pores on epidermal layer called
Stomata
What is interior to the epidermis
Cortex
What is the cortex mainly made up of
Parenchyma cells
What is the location of collenchyma cells in the primary structure of dicto root
Just beneath the epidermal layer to provide strength
What is the types of cells found in cortex to provide support
Sclerenchyma such as fibres
How are the vascular bundles arranged in a dicot stem
In a ring
Describe the arrangement of vascular bundles in dicot stems
Primary phloem towards cortex
Primary xylem towards pith
In-between a cambium tissue
What is outside vascular bundles
Luster of sclerenchyma cells
What is found inner to the vascular bundle
A large pith made up of parenchyma cells
From where does the lateral shoots form
From lateral buds
What is the nature of ground tissue of monocot stem compared to dicot stem
Ground tissue is not differentiated into cortex and pith
What is the arrangement of vascular bundles in most monocot stems
The vascular bundles are scattered throughout the ground tissue in most monocot stems
What surrounds the vascular bundle of monocot stem
Schlerenchyma
Does monocot stem vascular bundle have cambium in between xylem and phloem
No
Does monocot stem vascular bundle have cambium in between xylem and phloem
No
