Simple Permanent Tissue Flashcards
a basic unit of an organ
Cell
A group of cell having essentially a common function and origin is called as
tissue
Plant tissues are classified into two main groups
Meristematic tissue
Permanent tissue
It is a group of young living cells with ability to divide in the regions where they are present.
MERISTIMATIC TISSUE
Growth in plants is restricted to specialized region of active cell division called
meristem
are isodiametric in shape without intercellular space
Meristematic cells
Cell wall is thin, elastic mainly composed of cellulose
Meristematic cells
Protoplasm is dense with distinct nucleus at center and with small vacuoles if present.
Meristematic cells
Cells are immature and shows high rate of metabolism.
Meristematic cells
3 Classifications of meristems:
- Origin
- Position and
- Function:
3 origins of meristems
Primordial meristem or Promeristem
Primary meristem
Secondary meristem
Usually occupying very minute area at the tip of root and shoot and also called as embryonic meristem
Primordial meristem or Promeristem
Originates from primordial meristem and occur in
plant body from beginning at the root and shoot apices and contribute in the formation of primary plant body
Primary meristem
are tissues develop from living permanent tissues during later stages therefore called as secondary meristems
Secondary meristem
They are responsible for producing secondary tissues and
occur in mature region of root and shoots of many plants
Secondary meristem
They are always lateral in position e.g. fasicular cambium, inter fasicular cambium, cork cambium
Secondary meristem
3 positions of meristems
Apical meristem
Intercalary meristem
Intercalary meristem
The meristem that occurs at tips of roots and shoots and
produce primary tissues
apical meristems
where does apical meristems occupies when in roots
tip of the root
where does apical meristems occupies when in shoots
most region of stem axis
The meristem which occurs between mature tissues is known as
Intercalary meristem
It is present in the top and base area of
the node
Intercalary meristem
They are short lived and their activity is mainly seen in monocots
Intercalary meristem
It is present along the side of central axis of organs and
takes part in increasing girth of stem and root e.g. intrafacicular
cambium.
Lateral meristem
is also known as secondary meristem
Lateral meristem
what are the 2 meristems known as primary meristem
apical meristems and intercalary meristem
3 functions of meristems
Protoderm
Procambium
Ground meristem
In young growing regions of plant, the protective covering like
epidermis around various organs is called as
protoderm
It helps in producing secondary vascular tissue
Procambium
what are the 4 parts that are formed by ground meristems
cortex
endodermis
pericycle medullary rays
pith
Structures like cortex, endodermis, pericycle medullary
rays and pith are formed from
ground meristems
these tissues do not generally divide further and acquired
permanent shape size and function.
permanent tissue
there are two types of permanent tissues
Simple Permanent
Complex Permanent
a permanent tissues having all cells similar in
function
Simple Permanent
tissues having many different type of cells
Complex Permanent
It is made up of only one type of cell carrying similar function
Simple permanent tissue
This tissue is either living or dead
Simple permanent tissue
3 types of simple permanent tissues
- Parenchyma
- Collenchyma
- Sclerenchyma
It forms the major component within the organs.
Parenchyma
cells are thin walled made up of cellulose, isodiametric,
round, oval to elongate in shape.
Parenchyma
Cells are living with prominent nucleus
and cytoplasm with large vacuole
parenchyma
Cells may be closely packed or having
intercellular space
parenchyma
These cells are distributed in all parts of plant body viz.
Epidermis, cortex, pericycle, pith, xylem and phloem.
parenchyma
these tissues performs various functions like storage of food and water, helps in gaseous exchange, perform photosynthesis
parenchyma
It is made up of living cell and occurs in layer below the epidermis in most of the dicotyledonous plants
Collenchyma
It is either found in homogenous layer or patches
Collenchyma
its Cell wall is cellulosic but shows uneven deposition of cellulose, hemicelluloses and pectin especially at corners.
Collenchyma
Cells similar to parenchyma containing cytoplasm, nucleus and vacuoles but small in size and without intercellular space.
Collenchyma
Cells may be oval, spherical or
polygonal contain chloroplast
collenchyma
It provides mechanical support to young growing parts of plants such as young stem and petiole of leaf
Collenchyma
allows bending and pulling action in plant parts, prevent tearing of leaf also helps in growth of organs and elongation
Collenchyma
It consists of long, narrow cells with thick walled dead cells
Sclerenchyma
Cells are living at the time of production but at maturity they become dead.
Sclerenchyma
Fibres are thick walled, thread like, elongated and narrow with tapering and interlocking end
Sclerenchyma
they are generally occurs in groups, in various parts of the plants and provide mechanical strength to the plant
Sclerenchyma
Scleroids are usually spherical, oval, highly thickened dead cells with narrow cavities or lumen
Sclerenchyma
provides mechanical support to organs, permits bending and
pulling, also give rigidity to epicarps and seeds
Sclerenchyma
Commercial fibres are also
produced from
Sclerenchyma
are also produced from Sclerenchyma fibres e.g. jute
Commercial fibres
