Botany Lec - Module 4: Plant Histology

PLANT HISTOLOGY

Study of tissues

histos

meaning “tissue”

logia

meaning “study of”

PLANT TISSUE

group of closely associated cells that perform related functions and are similar in structure

TISSUE

a group of cells performing a common function

PLANT TISSUE SYSTEM

functional unit of plant tissues

DERMAL, GROUND, AND VASCULAR

types of plant tissue system

MERISTEMATIC AND PERMANENT TISSUE

Type of Plant Tissue

MERISTEMATIC TISSUE

regions where cell division produce plant growth; site for cell division; where tissues originate

SHOOT APICAL MERISTEM

Type of apical meristem that produces leaves, stems, and flowers; upper part of the plant

ROOT APICAL SYSTEM

Type of apical meristem that produces roots; underground part of the plant

APICAL MERISTEMS

meristematic tissues found at the tip of roots and shoots, which increase in length as it produces new cells; responsible for primary growth

LATERAL MERISTEMS

increase width of stems and roots; responsible for secondary growth

VASCULAR CAMBIUM

Type of lateral meristem; produces vascular/secondary tissues, for support and conduction

CORK CAMBIUM

Type of lateral meristem; runs the length of roots and stems of woody plants. It lies outside the vascular cambium.

INTERCALLARY MERISTEM

neither vascular / cork cambium; have apical meristems in the vicinity of nodes

PERMANENT TISSUE

Tissues that does not undergo cell division

COMPLEX AND SIMPLE TISSUE

Type of meristematic tissue

COMPLEX TISSUE

more than one type of cell

SIMPLE TISSUE

only one type of cell

PROTODERM, GROUND MERISTEM, AND PROCAMBIUM

3 primary Meristem

PROTODERM

outermost and form epidermis

GROUND MERISTEM

Ground tissue ie cortex and pith

PROCAMBIUM

innermost; where primary vascular tissues is found

DERMAL TISSUE

complex tissue; protects the soft tissues of plants and controls interactions with the plants surroundings

EPIDERMIS

protects the soft tissues of plants and controls interactions with the plants surroundings.

CUTICLE

Epidermis secretes a waxy layer called the ____ that inhibits water loss

EPIDERMIS, MESOPHYLL, AND VEINS

3 regions of internal anatomy of leaves

PERIDERM

replaces epidermis (in young plants)

VELAMEN ROOTS

aka aerial roots

CUTIN

Fatty substances which composes the cuticle

LENTICELS

gas exchange in the epidermis

PERIDERM

constitutes the outer bark and is primarily composed of somewhat rectangular and boxlike cork cells, which are dead at maturity

SUBERIN

Fatty substance in the periderm

MESOPHYLL

location where most of the photosynthesis takes place

PALISADE MESOPHYLL

upper region with compactly stacked barrel shaped or post shaped parenchyma cells in two rows; with 80% of leaf chloroplast

SPONGY MESOPHYLL

lower region containing loosely arranged parenchyma cells with lots of air spaces between them, with cells having-numerous chloroplasts. NOT IN MONOCOTS

GROUND TISSUE

simple tissues are involved in photosynthesis, storage, regeneration, support, and protection

PARENCHYMA

have thin cell walls and large vacuoles and are most abundant of all the cells; Intercellular space is found; perform photosynthesis and store protein and starch.

COLLENCHYMA

composed of elongated cells and have thick cell walls; provide support for growing tissues, like stem

SCHLERENCHYMA

dead at maturity; composed of narrow dead thick-walled cells, impregnated with lignin; provide support for the plant

VASCULAR TISSUE

complex tissue; composed of xylem and phloem, which function in the transport of water and dissolved substances; transports material between the root and the shoot of the plant.

XYLEM

aka Conduction schlerenchyma; conducted water and dissolved minerals; conducting cells are dead and hollow at maturity

VESSELS

long tubes composed of individual cells

TRACHEIDS

are dead at maturity and have relatively thick secondary cell walls, are tapered at each end, the ends overlapping with those of other tracheids.

PHLOEM

conducts dissolved food materials (primarily sugars) produced by photosynthesis throughout the plant

SIEVE-TUBE MEMBERS

main conducting cells of phloems

COMPANION CELLS

assisting the loading of the sugars in the phloem

PITH

soft central portion and its central portion is surrounded by vascular bundles

ENDODERMIS

layer of cell between cortex and vascular tissue in roots (help to regulate water loss)

PERICYCLE

In dicot roots, it strengthens the roots and provides protection for the vascular bundles.

PITS

are depressions in cell walls where the secondary walls does not form

TRICHOMES

Hairs of a different nature occur on the epidermis of aboveground parts of plants

STOMATA

Pores on the leaves in charge of gas exchange

GUARD CELLS

pairs of specialized epidermal cells bordering the stomata

GLANDS

that secrete protective or other substances, or modified as hairs that either reduce water loss or repel insects and animals that might otherwise consume them