Plant Tissues Flashcards
An ensemble of similar cells that carry out a specific function
Tissue
Mutiple tissues forms?
Organ
2 Kinds of Meristematic Tissues
- Shoot Apex
- Root Apex
Simply called the meristem
Meristematic Tissue
Embryonic tissue
Meristematic Tissue
has the capacity to divide into new cells to produce morecells
Meristematic Tissue
Describe meristematic cells
thin walled living cells
with dense cytoplasm
with a large nucleus
Parts of the apical meristem
- Shoot
- Roots
Parts of the intercalary meristem
Node
Parts of the lateral meristem
Stem
found at the tip of stems and roots
causes primary growth (increase in length of plant) as they produce new cells
produces new leaves and flowers
Apical Meristems
found at the tip of stems
Shoot Apex
found at the tip of roots
Root Apex
Primary meristems (found in shoot and root apical meristems):
protoderm, ground meristem, and procambium
Aka cambia
- found along the sides of roots & stems
- produces secondary growth (increase in width or diameter of stems & roots)
- produces bark of trees
Lateral Meristems
the outermost layers of stems and roots of woody plants
Bark
responsible for increasing the diameter of stems and roots and for forming woody tissue
vascular cambium
produces some of the bark
cork cambium
found in the vicinity of nodes (leaf attachment areas) whichoccur at intervals along stems
Intercalary Meristem
responsible for further increase in length of stems andleaves
Intercalary Meristem
are short-lived since they are eventally transformedintopermanent tissues
Intercalary Meristem
is formed by the division of meristematic cells. The cells of these tissues have lost the power of division
permanently.
Permanent Tissues
composed of only one kind of cell (similar cells) that performs a common function
Simple Permanent Tissues
composed of several kinds of cells that performa common function
Complex Permanent Tissues
Explain parenchyma
- living tissues
- most abundant ; has the most basic/simple type of cells
- cells are more or less spherical in shape; cells are usually isodiametric (equal diameters) - cells have thin cell walls with large vacuoles
- there are spaces in between cells
- Parenchyma is seen in complex tissues like Xylem and Phloem
- generally funtion for food and waste storage. The edible parts of most fruits and vegetables
consist largely of parenchyma.
Explain Collenchyma
- living tissues
- thick cell walls (uneven thickness)
- cell walls are strong and lignified
- commonly found below the epidermis
- they are longer than they are wide
- usually smaller than parenchymal cells
Sclerenchyma
- dead tissues at maturity but function as supporting tissues in plants
- cells are thick and tough-walled
- cell wall also has lignin
for stiffness and allows plants to grow upright
Lignin
Equal diameters
isodiametric
a single layer of cells that covers plants
Epidermis
wall deposited inside the primary cell wall
Secondary Cell Wall
product of photosynthesis; storehouse of glucoseunits
Starch Grain
Potato contains what simple tissue?
Parenchyma tissue
Celery contains what simple tissue?
Collenchyma tissue
Pear contains what simple tissue?
Sclerenchyma tissue
Simple tissues with both thick and thin primary cell walls
Sclerenchyma
It only has thick primary cell wall in longitudinal cut
Collenchyma
It has thin primary cell wall
Parenchyma
Explain aerenchyma
- with plenty of intracellular space as larger air cavities/channels
- forms a spongy tissue because of air cavities
- present in aquatic plants, and its function is to provide buoyancy tothe plant
Explain chlorenchyma
- has chloroplasts, hence, contains chlorophyll (green pigment)
- usually present in the tissue of leaves
Explain prosenchyma
- elongated cell that gives mechanical support
- cells are
interpenetrating pointed ends
stores food material
Storage Parenchyma
stores water (Succulents)
Water storage tissue
retains water in dry climates or soil conditions.
Succulent
type of collenchyma seems polygonal in shape. The thickening pattern of the cell wall is towards the corner.
Angular Collenchyma
type of collenchyma that consists of rounded cells and possesses invariably thickened
cell wall
Annular Collenchyma
“plate or tangential collenchyma”, possesses longitudinally
elongated cells. The intact rows of cells are arranged tangentially, leaving no intercellular
spaces
Lamellar Collenchyma
“tubular collenchyma”, cells have large intercellular spaces
called ‘Lacuna’. It possesses spherical or oval-shaped cells.
Lacunar Collenchyma
They are commonly found below the epidermis (a single layer of cells that coversplants)
Collenchyma
very elongated cells that can be found in stems, roots, and vascular bundles in leaves; have a tiny cavity or lumen at the center of the cell
Fibers
short and are irregular in shapes, responsible for gritty texture of chico and pears
Sclereids (stone cells)
space that is found inside cell
Lumen
thinner portions of the cell wall
Pits
Tissues with different kinds of cells that perform similar function. They are mainly helpful in conduction.
Complex Tissues
conducts water
and minerals
Xylem
conducts sugars
and other organic
compounds
Phloem
cell walls with holes
Perforated cell walls
is the water conducting tissue and also provides mechanical support. It originates from two sources like procambium and the vascular cambium
Xylem
The first formed cells of xylem
protoxylem and metaxylem
produces primary xylem on the inner side and primary phloem on the outer
Intrafascicular cambium
are dead with thick lignified walls; similar to schlerenchyma
Xylem Fibers
smaller than size than ordinary parenchyma cells
Xylem Parenchyma
long tubes made up of individual cells; shorterandmuch wider than tracheids
Xylem vessels
elongated with tapering (narrowing) ends
Tracheids
conducts water, minerals and gives mechanical support. It originates from two sources like procambiumand vascular cambium.
Phloem
The first formed cells of phloem
protophloem and metaphloem
elongated cells joined end to end,forming sieve tubes. Their end walls have a large number of small pored called sieve plates and are living cells that do not have nuclei.
Sieve Elements/Sieve Tube Elements
small, nucleated, elongated parenchymous cells which support sieve tubes
Companion Cells
dead cells with tappering ends, look like schlerenchyma
Phloem fibers
living and thin walled cells, look likeparenchyma
Phloem parenchyma
located outside of phloemitself
phloem fiber
Explain secretory or special tissues
The cells or tissues that are concerned with secretion or excretion from the plant body.
They are located in different parts of the plant body and are widely distributed.
Many plant secretions are of high considerable economic
importance.
They include nectars and oils.
They are found in insectivore plants and secrete proteolytic enzymes.
Digestive glands
Give an example of digestive glands
Nepenthes/Pitcher Plant
enzymes that break down protein
proteolytic enzymes
They are called as nectaries.
They secrete sugary substance called nectar which attracts insects and promote pollination.
Nectar glands
nectaries in floral regions
floral nectaries
other than floral regions
extra floral nectaries
Example of a plant with nectar glands
Carnation (Dianthus caryophyllus)
They are special glands which produce volatile essential oils andimpart fragrance to flowers.
Osmophors
examples of osmophors
orchids specifically,
(Coryanthes macrantha / Bucket Orchid)
The secretions released are stored in the spaces within the gland. These are formed by the breakdown of secretory cells.
Secretory cavities
formed by the death of the secretory cells
Lysigenous cavities
formed by the enlargement of intercellular space
between secretory cells
Schizogenous cavities
example of a plant with secretory cavities
Eucalyptus tree (Eucalyptus globulus)
an essential oil for nasal congestion
Essential oil
Example of an hydathode
Tomato (Solanum lycopersicum formerly Lycopersicon esculentum)
Aka water stomata
Water is forced out in the form of drops through water pores
Hydathodes
removal of water from the hydathodes
Guttation
removal of water from the stomata on the leaves
Transpiration
present on the margins of leaf where the vascular supply (vein) ends.
Hydathodes
present on the epidermis of leaf, youngstem and floral parts
Stomata
are specialized parenchyma cells which secrete a viscous fluid,known as latex (milky liquid).
Laticiferous Tissues
example of laticiferous tissues
Preparation of rubber from Ficus elastica /rubber tree
Milky liquid in laticiferous tissues
latex
found inner than phloem
xylem
Explain ground tissues
Simple (Permanent) tissues
Store molecules (such as starch), photosynthesize, or support the plant
Often divided into 3 types: Collenchyma, sclerenchyma, and parenchyma
Explain dermal tissues (epidermis)
Complex (Permanent) tissues = multiple cell types
Covers the plant and can be found on the outer layer of roots, stems and leaves
Main functions: gas exchange and defense, transpiration (water movement and its evaporation from aerial parts of plants, such as leaves, stems and flowers)
Vascular Tissues
Complex (Permanent) tissues = multiple cell types
Conducts water, minerals, and dissolved sugars from photosynthesis topassthroughroots, stems, leaves, and other parts of the plant
2 types of vascular/conducting tissue
xylem and phloem
part of the transport system in vascular plants; supporting and protective tissues
vascular bundle
located in the center of the vascular bundle, deep in the plant
xylem
located on the outer side of the vascular bundle
phloem
