Plant StructureAquaponics

Plant Body• Shoot system = leaves

+ stem• Root system• Meristem = cells that

divide for life of plant, can give rise to all plant structures

3 BASIC Organs– Roots– Stems– Leaves

2 BASIC Systems• BOTH SYSTEMS DEPEND ON

THE OTHER– Root System (roots) receive sugars

and other nutrients from photosynthetic parts

– Shoot System (leaves and stems) depends on water & minerals absorbed from the soil by roots.

The plant body cells tissues organs

• A tissue = group of cells with a common structure and function

• An organ = several types of tissues that work together to carry out particular functions

Tissue Types in Vascular Plants• Dermal Tissue

– Covers/ protects plant– Makes cuticle on stems/ leaves– Allows for better H2O absorption

(root hairs)– Make guard cells

• Vascular Tissue (xylem & phloem)– Transport and support– Throughout the plant– Called “veins” in leaves– Called the “stele” in stem or root

• Ground Tissue– Between dermal and vascular tissues– Storage– Photosynthesis (makes sugars)– Support

Dermaltissue

Vasculartissue

Groundtissue

MONOCOT PLANTS vs. DICOT PLANTS

Plant Body- ROOTSRoot Functions

Anchors plant in soil Takes up water and minerals from soil

& gymnosperms

Eudicot and Monocot Roots

Mono = 1 (1 BIG circle)

Eudicot and Monocot Roots• Epidermis-outer layer of

root that protects the underlying tissues of the root.

• Cortex-the inner side of the epidermis. Allows diffusion of water, mineral salts, and oxygen from the root hairs. Stores foods, especially starch.

• Endoderims-Active mineral uptake

Modified Roots• Some plants have modified

roots • Adventitious roots arise

aboveground spread over large areas

• Storage roots hold “food” called root tubers

Plant Body-STEMStem: series of nodes and internodes

FunctionsSupport for the plant body Holds leaves up to light

Transports nutrients throughout plant

Xylem conducts waterand minerals

Phloem transports sugar

Connect roots and leaves and support plant

Eudicot and Monocot Stems

Tissue Organization of Stems• Most Eudicots– vascular tissue consists of vascular bundles that are

arranged in a ring• Most Monocot stems– the vascular bundles are scattered throughout the

ground tissue, rather than forming a ringPith: in young stems, the pith stores food. The pith disappears in older stems.

Cambium: during growing season, cambium produces new phloem to the outside and new xylem to the inside.

Division of Meristem Cells Causes Plant Growth

• Apical Meristem– tips of root and

shoot– increase in height

• Lateral Meristem– cylinders within

plant body– increase in width

• Apical meristems are located at the tips of roots and in the buds of shoots– elongate shoots and roots, a process called primary

growth• Lateral meristems

– add thickness ONLY to woody plants, a process called secondary growth

– 2 lateral meristems: the vascular cambium and the cork cambium• vascular cambium adds layers of vascular tissue

called secondary xylem (wood) and secondary phloem• cork cambium replaces the epidermis with

periderm, which is thicker and tougher (bark)

Types of Meristems (like embryonic stem cells)

Woody Stem GrowthThe stem has three areas: •Bark•Wood•pith

CORK-protects the outer part of the bar

SPRING WOOD (early wood): the part of an annual ring of wood, characterized by large, thin-walled cells, formed during the first part of the growing season.

SUMMER WOOD (late wood): the part of an annual ring of wood, characterized by compact, thick-walled cells, formed during the later part of the growing season.

LE 35-18b

0.5 mm

Vascular cambiumSecondary phloem

Secondaryxylem

Transverse sectionof a three-year-old Tilia (linden)stem (LM)

Late woodEarly wood

0.5 mm

Cork cambium

Cork

Periderm

Xylem rayBark

HOW OLD IS THIS TREE?

Plant Body-LEAF REVIEW

Functions Exposes surface to sunlight

Major site of photosynthesisConserves waterProvides for gas exchange

Blade

Petiole

Leaf = blade + petiole

Stoma = opening in the leaf for

gas exchange, water evaporation

Monocots & Eudicots Leaves• Monocots lack petioles – Base of leaf forms a sheath that envelops stem– Have parallel veins (run length of the blade)

• Eudicot (dicot) have petioles & leaves have a multibranched network of major veins.– Petiole • Only Eudicots NOT Monocots

petiole

Flowering Plant Reproduction

• Flowers are modified leaves, specialized for reproduction (where pollination takes place).

• Flower parts undergo meiosis to produce haploid products– pollen grain– ovule (contains egg cell)

Pollengrains

Ovule

Flower

Meiosis

Mitosis

Mitosis

Development of Fruit and SeedsFrom Flower Parts

TriploidEndosperm

Cell

Ovary

Integument

DiploidZygote

Endosperm

FreshFruit

SeedCoat

Embryo(new plant)

Seed = embryo + stored food + seed coatFruit = ovary wall, mechanism for seed dispersal

Provides nutrition

Flowers, Fruits, and vegetablesA fruit is the part of the plant that develops from a flower. It's also the section of the plant that contains the seeds. (Protects the seeds).

The other parts of plants are considered vegetables. These include the stems, leaves and roots — and even the flower bud.

Dead Center sits the tomato. Why?Botanically speaking, a tomato is a fruit because it is a seed-bearing structure that develops from the ovary of a flowering plant.

In the culinary world sweet = fruits and savory = vegetables: this includes botanical fruits as eggplants, bell peppers, and tomatoes.

Angiosperm Classification and Morphology

– Monocots: grasses, lilies, orchids, corn, palms, onions– Dicots (aka-Eudicots): broadleaf trees, shrubs, most flowers, and

vegetables.

Exit Slip-March 12, 2014

• Draw a picture of a monocot and dicot cross section of a ROOT.

• Draw a picture of a monocot and dicot cross section of a STEM.