1.
BOT 2150 C
Plant classification
Lecture 1, May 11

2.
What makes a plant?
• Photosynthetic and contain chlorophyll a & b
• Multicellular
• Alternates between two generations
• Produces embryos
• Has cell walls made of cellulose
• Mushrooms are not plants!

3.
Plant kingdom
Non-vascular Vascular (Tracheophyta)
Plants without seeds
Mosses
Liverworts (Seedless vascular Plants with seeds
(very moist areas) plants) (seeded vascular plants)
Horsetails
Ferns
Gymnosperms: Angiosperms:
Fronds & cones flowers & fruits
spores
Wetter areas

4.
Gymnosperms
page 2
Conifers
Often trees with needle-like or scale-like leaves, male and female cones;
female cones produce seeds (includes Podocarps)
Cycads
Large, pinnately compound leaves, male and female cones, cones large
and colorful; female cones produce seeds
Others:
Ginko biloba
Gnetales

5.
angiosperms
Monocots – one seed cotyledon, parallel leaf veins, flowers with
multiples of 3 (3, 6, 9), stems lack secondary growth, most are
herbaceous, fibrous root systems
Eudicots – (dicots), 2 seed cotyledons, veins are usually netted,
flowers are in multiples of 4 or 5, stems may have secondary growth,
many are herbaceous, many are woody, tap root systems (fleshy
included in this category)
Others: Basal angiosperms
Includes groups that are not monocots or eudicots
Ex: water lily

6.
Plant Monocot “Dicot”
characteristic
Plant 2,700/ 58,000 9,900/175,700
genera/species
(approx.)
Cotyledons 1, usually develop 2, usually develop
underground or above the ground
inside the fruit
Mature root adventitious, often Mostly taproot
system above ground, often system,
prop roots occasionally
adventitious
Leaf venation Usually parallel Usually netted

7.
Stem Scattered; Arranged in a ring
appearing around the stem; pith
random distinct
Cambium Usually absent - Usually present – “true”
no true secondary growth
secondary
growth
Habit herbaceous Woody or herbaceous
Floral parts Typically in Typically in multiples of
multiples of 3 4 or 5
Propagation Underground stem or seed Propagate from stem or leaf cuttings (success
depends on the species and various techniques);
seed, some tubers or underground stems will
grow.

8.
Scientific names
Individual: Theobroma cacao Quercus virginiana
Cacao Live Oak
Classification
Kingdom Plantae Plantae
Division (Phylum) Magnoliophyta Magnoliophyta
Class Angiospermae (flowering Angiospermae (flowering
plants) plants)
Order Malvales Fagales
Family Malavaceae (hibiscus family) Fagaceae
Genus (pl. genera) Theobroma Quercus
Species Theobroma cacao Quercus virginiana
Just remember: King David Came Over For Good Soup

9.
Other terms
Other terms Hybrids
Subspecies: ssp. Species hybrid: Cattleya skinneri X
guatemalensis
Variety: var.
Cultivar (cultivated variety): Variety hybrid: Maypan (Malay dwarf
cv “Malay dwarf” or “big boy” X Panama tall)

10.
activity
• Plants in the room – identify to basic group
• Moss (non-vascular), fern, gymnosperm,
angiosperm
• Nursery tour

11.
Vegetative characteristics-stems
• Support structure of the plant
• Hold leaves
• Figure 22 page 9
• Read specialized stem structure pages 9-15

12.
http://www.pssc.ttu.edu/techhort/IMAGES/leaves/node.jpg

13.
Vegetative characteristics-
leaf function
• Leaves – primary photosynthetic organ
• Take in sunlight, carbon dioxide, and water
and convert it into sugars

14.
www.paulnoll.com/Oregon/Wildflower/leaf-parts.jpg

15.
Vegetative characteristics- leaf type
page 20

16.
Vegetative characteristics- leaf shape
page 17
spatulate deltoid
sagittate
margins

17.
Vegetative characteristics- leaf margin
page 19

18.
Vegetative characteristics- leaf arrangement
page 20

19.
activity
• Two example stems
• For each stem determine:
– 1. leaf type
– 2. leaf shape
– 3. leaf arrangement
– 4. leaf margin

20.
Reproductive organs
• Flowers & fruit – only in angiosperms (pg 28-32)
Collectively
Collectively = calyx
= corolla
pedicel

21.
Flower terminology cont.
• Perfect – contains all parts, both male
(stamens) and female (pistil)
• Imperfect – does not contain all parts, only
male or female flower
• Naked flower – usually wind pollinated, no
petals or sepals, often imperfect

22.
Reproductive organs - inflorescence
• Flowers are found on a stem (peduncle)
• The flowering stem with flowers is called an
inflorescence
• Page 23-27

23.
Inflorescence types

24.
activity
• Dissect 3 flowers and label the parts
• For each flower, determine:
– 1. perfect or imperfect
– 2. ovary superior or inferior
– 3. monocot or eudicot

25.
Homework & activities to turn in
• 1. turn in keyed out leaf – 2 examples
• 2. flower diagrams – 3 flowers
• Assigned reading: Botany Handbook for
Florida – full booklet