PLANT STRUCTURE AND FUNCTION (THE LAST CHAPTER!!)

PLANT STRUCTURE AND FUNCTION

(THE LAST CHAPTER!!)

PLANT STRUCTURE AND FUNCTION

• MONOCOTS VS DICOTS

PLANT STRUCTURE AND FUNCTION

• ORGAN SYSTEMS– ROOT SYSTEM• FUNCTION??

– SHOOT SYSTEM• MADE UP OF STEMS AND LEAVES• FUNCTIONS??

PLANT STRUCTURE AND FUNCTION

• ROOTS– FUNCTIONS??– TYPES??• TAPROOT VS FIBROUS

– ROOT HAIRS• FUNCTION??

PLANT STRUCTURE AND FUNCTION

• STEMS– FUNCTION??– NODES VS INTERNODES?

PLANT STRUCTURE AND FUNCTION

• LEAVES

PLANT STRUCTURE AND FUNCTION

• MAJOR TYPES OF PLANT CELLS– PARENCHYMA CELLS– COLLENCHYMA CELLS– SCLERENCHYMA CELLS– TRACHEIDS AND VESSELS*– SIEVE-TUBE CELLS ANDCOMPANION CELLS*

PLANT STRUCTURE AND FUNCTION

• MAJOR TYPES OF TISSUES– THREE TYPES• DERMAL• GROUND• VASCULAR

– XYLEM VS PHLOEM

PLANT STRUCTURE AND FUNCTION

• PLANT GROWTH– PRIMARY VS SECONDARY• PRIMARY GROWTH IS VERTICAL• SECONDARY GROWTH IS HORIZONTAL

– SECONDARY GROWTH IN WOODY DICOTS IS UNIQUE

PLANT STRUCTURE AND FUNCTION

• SECONDARY GROWTH IN WOODY DICOTS– UNIQUE STRUCTURES– VASCULAR CAMBIUM– CORK CAMBIUM– CORK– PRIMARY VS SECONDARYXYLEM**

PLANT STRUCTURE AND FUNCTION

• REPRODUCTION

PLANT STRUCTURE AND FUNCTION• POLLINATION

– TWO TYPES• WIND VS ANIMAL

• MAJOR STRUCTURES TO REMEMBER– OVULE develops into the seed

– COTYLEDON “SEED LEAF”; may become the embryonic first leaves of a seedling

– RADICLE is the embryonic root of the plant, and grows downward in the soil

– HYPOCOTYL primary organ of extension of the young plant and develops into the stem

– EPICOTYL embryonic shoot above the cotyledons. In most plants the epicotyl will eventually develop into the leaves of the plant

– SEED COAT

PLANT STRUCTURE AND FUNCTION

• OVARY DEVELOPS INTO A FRUIT

PLANT STRUCTURE AND FUNCTION

• GERMINATION**

PLANT STRUCTURE AND FUNCTION

• VEGETATIVE REPRODUCTION VS VEGETATIVE PROPAGATION

PLANT STRUCTURE AND FUNCTIONHORMONES!!!!

Where Found in Plant Major Functions

AuxinEmbryo of seed, young leaves, meristems of apical buds

Stimulates cell elongation; involved in phototropism, gravitropism, apical domincance, and vascular differentiation; inhibits abscission prior to formation of abscission layer; stimulates ethylene synthesis; stimualtes fruit development; induces adventitious roots on cuttings

CytokininSynthesized in roots and transported to other organs

Stimulates cell division, reverse apical dominance, involved in shoot growth, delay leaf sequence

EthyleneTissues of ripening fruits, nodes of stems, senescent leaves and flowers

Stimulates fruit ripening, leaf and flower senescence, and abscission

Abscisic Acid

Leaves, stems, green fruit Stimulates stomatal closure

GibberellinMeristems of apical buds and roots, young leaves, embryo

Stimulates shoot elongation, stimulates bolting and flowering in biennials, regulates production of hydrolytic enzymes in grains

PLANT STRUCTURE AND FUNCTION

• TROPISM VS PERIODISM– PHOTOTROPISM• GROWING TOWARDS LIGHT (SLIGHTLY MISLEADING)

– PHOTOPERIODISM• LONG-DAY VS SHORT DAY• ACTUALLY EFFECT

BY HOURS OFDARKNESS