Plant Anatomy: An Overview
Simpson, MG (2006). Plant Systematics
Eames and McDaniels (1953). Introduction to Plant Anatomy
IntroductionDefinition• Plant anatomy –the study of the internal
structure of various parts of the plant
Applications of plant anatomy• Taxonomic application
– e.g. problem plants
• Proper authentication of crude drug material– For safety and quality to be maintained– Morphology and anatomy of drug source is
published in British and English pharmacopoeias
Introduction
Applications of plant anatomy
• Avoids food adulterants and contaminants
Sambong (Blumea balsamifera L)
Mango (Mangifera indica L)
•FORENSIC APPLICATIONS Forensic botany refers to the use of plant materials to help solve crimes or resolve other legal problems.
The first botanical testimony to be heard in a North American court concerned the analysis of the wood grain of the ladder used in the kidnapping of Charles Lindbergh Jr., and led to the conviction of Bruno Hauptmann for the crime in 1935.
Xylotomist Arthur Koehler of the United States Forest Service undertook a meticulous examination of the ladder and when the case finally came to trial four years later, offered the first botanical testimony ever to be heard and accepted in American courts.
LIVING ORGANISMS
Prokaryotes
Kingdom Monera
Eukaryotes
Unicell/simple multicellular organisms
Kingdom Protista
Multicellular organisms
Autotroph
Kingdom Plantae
Heterotroph
Saprophytes
Kingdom Fungi
Ingestion of other organisms
Kingdom Animalia
The five-kingdom system prevailed in biology for over 20 years.
LIVING ORGANISMS
•During the last three decades, systematists applying cladistic analysis, including the construction of cladograms based on molecular data, have been identifying problems with the five-kingdom system.
The Land Plants=Embryophyta (embryophytes)
• The first colonization of plants on land during the Silurian period, ca. 400 million years ago.
• Land Plants now dominate the earth.
GAMETOPHYTE(n)
Egg (n)
Sperm (n)
Zygote
(2n)
HAPLODIPLONTIC("Alternation ofGenerations")
SPOROPHYTE(2n)
Embryo(2n)
Spores(n)
lost by reduction and modificationin the Angiospermsand some Gnetales
Sporangium(2n)
Archegonium(n)
Antheridium(n)
fertilization
mitosismitosis
meiosis
mitosis
}
(Sperm non-flagellate in Conifers, Gnetales, and Angiosperms)
Sporocyte(2n)
produce
Marchantia (liverwort) Mnium (moss)
antheridium
antheridium
sperm cells
Marchantia (liverwort)
archegonium
egg cell
neck
“Bryophytes”
Liverworts
Hornworts
Mosses
•Vascular plants/ Tracheophytes- Xylem tissue, true roots, stems & leaves.
Fern and allies/ cryptogams: Spores but no seeds
1.Division Psilophyta (Psilotum or whisk fern)2.Division Lycophyta (club mosses)3.Division Sphenophyta (horsetails).4.Division Pterophyta (ferns).
Spermatophytes/ phanerogams: Seed Plants
•Gymnosperms--Naked Seeds
5. Division Cycadophyta (cycads)6. Division Ginkgophyta (maidenhair tree).7. Division Gnetophyta (mormon tea & Welwitschia).8. Division Coniferophyta (conifers)
•Angiosperms--Seeds Enclosed In A Fruit
9. Division Anthophyta (flowering plants)
Selaginella
Lycopodiella cernua
Equisetum
Psilotum
GENERAL STRUCTURE OF HIGHER PLANTS
Shoot Shoot systemsystem
leafleaf
bladebladeaxillary budaxillary bud
petiolepetiole
nodenode
vascular tissuevascular tissue
vascular tissuevascular tissue
shoot apical meristemshoot apical meristemterminal budterminal bud
internodeinternode
vascular tissuevascular tissue
root tiproot tip
Lateral rootsLateral roots
root caproot cap
root apical meristemroot apical meristem
RootRoot systemsystem
dermal tissuedermal tissueground tissueground tissuevascular tissuevascular tissue
Stelar types
eustele atactostele
Pericycle
Plant Tissues & Cell Types
Tissue:
= group of cells with common function or structure.
Three broad tissue types:
1) Dermal - outside layer(s)
2) Vascular - conduction
3) Ground - between dermal and vascular
Simple vs. Complex Tissue:
1 versus 2 or more cell types
Ground Tissue
Parenchyma: Gen. metabol.
1) Isodiametric to elongate
2) Primary cell wall
3) Living
Collenchyma: support
1) Elongate
2) Primary cell wall thick, uneven, rich in pectins
3) Living
Ground Tissue
Sclerenchyma
1) Secondary cell wall (+ primary)
2) Dead at maturity (usually)
Fibers
Elongate, sharply tapering
Ground Tissue
Sclerenchyma
1) Secondary cell wall (+ primary)
2) Dead at maturity (usually)
Sclereids
Isodiametric to irregular
3 recognized vegetative organs
• ROOT
• STEM
• LEAF
- Distinguished by the relative distribution of the vascular and ground tissues
ROOT vs Stem
ROOTS vs STEM
Leaves
Vascular Bundles of similar dimensions.
have a large central Vascular Bundle called a Midrib
DEVELOPMENT OF THE PLANT BODY
• Carpels and stamens– Contain the sporangia
• Sporangium– Contains the spores
– Chambers where male and female gametophytes develop
• Male gametophyte– Sperm-containing pollen grain
• Female gametophyte– Egg-containing structures called embryo sacs
– Embryo sac develop within the ovules
• Development of male gametophyte (Pollen)
• Development of female gametophyte (Embryo sac)
• Pollination
integument
funiculusmicropyle
POLLINATION
Embryogenesis
1. Transversie and Asymmetric division---Establishment of polarity
Terminal cell– embryoBalsal– suspensor
2. Organizaation of Tissue system
During the early stages of embryogenesis, cell divisiontakes place throughout the young sporophyte. Asthe embryo develops, however, the addition of newcells gradually becomes restricted to opposite ends ofthe axis, the apical meristems of future root and shoot
Seed GerminationSeed Dormancy