Chapter 3Introduction to plant structure

Organization of the vascular plant body

CellsCells Tissues Organs

Meristems – meristematic cells, initialsDerivatives – differentiated, non-meristematic, specialized cells

Cells

Meristems & growth– Apical meristems & primary

growth– Lateral meristems & secondary

growth

Primary growth

Figure 3.15

Apical meristems

3 primary meristems– Protoderm– Ground meristem– Procambium

Lateral meristems

Secondary growth (woody plants)– Vascular cambium– Cork cambium

Secondary growth & plant life cycles

Herbaceous plants vs. woody plants Annuals, biennials, perennials

Intercalary meristems

Stem elongation in grasses

Organization of the vascular plant body

Cells

TissuesTissues Organs Dermal

GroundVascular

Dermal tissues

Epidermis

Epidermis

Cuticle

Would you expect root epidermis to have cuticle?

EpidermisTrichomes

Epidermis

Dermal tissues

Periderm

Cypress bark

Maple bark

Pine barkOak bark

Periderm (bark)

Dermal products

Cuticle & Carnauba wax

Trichomes & Terpenes

Lipid-based Essential oils

– Citronellol– Camphor– Mints (Mentha)– Menthol

Pyrethrins

A terpene antimicrobial & anti-feedant

Ground tissues

Parenchyma– Chlorenchyma

Ground tissues

Sclerenchyma– Fibers– Sclereids

Sclereids

Sclerenchyma fibers

Sclerenchyma fibers

Important fiber crops

Hemp

Important fiber crops

Flax (linen)

Important fiber crops

Ramie

Jute

Bangladesh - #1 producer

Ground tissues

Collenchyma

Vascular tissues

Xylem Phloem

(EUDICOTS)

Vascular tissues

Vascular bundles in stems

Dicot root, c.s.

Xylem vessel Xylem tracheidPhloem

Vascular tissue Phloem

Sieve tube

Companion cell

Vascular tissues

Longitudinal sections

Cuticle is associated with which tissue(s)?

1. Epidermis

2. Sclerenchyma

3. Xylem

4. Ground tissue

5. All of these

Photosynthesis primarily occurs in

1. Epidermis

2. Ground tissue

3. Phloem

4. Collenchyma

5. Vascular tissue

Water transport is accomplished by

1. Dermal tissue

2. Ground tissue

3. Sclerenchyma fibers

4. Phloem

5. Vascular tissue

Organization of the vascular plant body Cells Tissues

OrgansOrgansShoot system

StemsLeavesFlowers

Root system

Plant growth & development

Seed plant embryos give rise to roots, stems and leaves of adult plant