Million years of evolution:

Angiosperm

Cooksonia

Angiosperms and plant anatomy

Practical # 3Mid-term evaluations (lab 6 of 10)LectureScavenger HuntTurn in cladistics worksheet p 123-4

Next week:Last lab practical

400mya

• http://www.johnkyrk.com/evolution.html

Paleo plant and insect interactions

Older Younger

Insects and plants evolved together

Rapid origin

time

The unique character of angiosperms is that the ovules are

completely enclosed in a carpel

1. gametophytes only a few cells

2. immotile sperm- carried to ovule by pollen tube

3. No “spores” because reduced gametophyte

Controversy about its floral morphology interpretation

Extinct

http://www.pbs.org/wgbh/nova/flower/anat-flash.html

http://www.pbs.org/wgbh/nova/flower/

Knowing the flower anatomy…let’s review the fossil record of earliest angiosperms

keep in mind:

• To date, the origin of the angiosperms remains controversial

• No consensus about the ancestral relative

• Molecular evidence suggest a Jurassic origin (>150 Ma), but the oldest fossils is early Cretaceous (~125 Ma)

MORE INFO: http://www.mobot.org/mobot/research/apweb/welcome.html

UF grad student found this one!

Extinct

Many early flowers arerelated to living

Angiosperms families

Pollination of ‘primitive’ flowers

Flowers adapted for pollination by "smart" insects

Insects can see uv light

Insects can see uv light

What pollinates these?

Wind-pollinated flowerssecondarily derived in Angiosperms

-- flowers are green, small, and often lack petals. Wind pollinated flowers of deciduous trees species open in early spring –

why?

Pick the Pollinator

http://www.pbs.org/wgbh/nova/flower/pollinator.html

Plant parts

Take a look…

Primitive vs Derived characters

• http://botany.csdl.tamu.edu/FLORA/tfplab/primder.htm

Fruit and seed dispersal

Don’t forget…

Also: ichthyochory

?

What disperses these?

Pleistocene extinction

Gomphothere

Late Pleistocene Extinctions

– 13,000 years ago, N & S America

“Re-wilding of N. America?”

Angiosperms often used for medicine – why?

Preparing ayahuasca

3 clades

A. Monocotyledones (monocots)

B. Magnoliids

C. Eudicotyledones (dicots)

ANGIOSPERMS

Generalized distinguishing characteristics:

MONOCOTSone cotyledon

parallel venation

scattered vascular bundles

floral parts in 3's

adventitious roots

pollen monosulcate

EUDICOTStwo cotyledons

reticulate venation

vascular bundles in rings

floral parts in 4's or 5's

taproots common

pollen tricolpate

MAGNOLIIDStwo cotyledons

reticulate venation

vascular bundles in rings

parts in 3's or numerous

taproots common

pollen monosulcate

A comparison of monocots and dicots -- know this for lab practical

Lab exercise – can you tell them apart?

All flesh is grass” -- Isaiah

Grasses evolved directly with mammals

MONOCOTS

Bamboo

Pineapple Onion

Banana

Palms!

Harvesting palm hearts

‘ivory palm’

Coconuts

Bactris gasipaes

‘peach palm’

One apical bud!!

Monocot stem -- vascular bundles

xylem

phloem

Dicot stem

Dicots have secondary growth

Xylem and phloem in rings

Which tree has a better chance to

live?

Monocot (palm)Dicot

Annual growth rings?

Illegal mahagony logging

Dicot stems

We eat many, many dicot fruitsExamples?

Theobroma cacao

In common?

Chinese kale

cabbage

Kale

Collard greens

Califlower

Brussel sprouts

Broccoli

Kohlrabi

Brassica oleracea

Chinese kale

cabbage

Kale

Collard greens

Califlower

Brussel sprouts

Broccoli

Kohlrabi

‘wild mustard’

Brassica oleracea

‘wild mustard’

Vavilov Centers of origin

for crop plants

http://www.hort.purdue.edu/newcrop/history/lecture05/lec05.html

Anatomy study slides

The life cycle of an angiosperm

Angiosperm life cycle

Plant morphology/anatomy

Primary vs. secondary growthA. Apical meristems - primary growth

B. Cambium (vascular or cork) - secondary growth

C. In lab -. Apical meristems1. Coleus - stem tip (no. 3) - herbaceous dicot

2. Zea - root longitudinal section (no. 4) - monocot

Seed anatomy Scan

StemsA. Anatomy

1.parenchyma (pith) 6. xylem2.sclerenchyma 7. phloem3.epidermis 8. vascular cambium4.cork & cork cambium 9. meristem5.cortex 10. node

B. In lab:1.Helianthus - stem (no. 5) - herbaceous dicot2.Tilia - stem cross sections (no. 6) - woody dicot3.Zea - stem cross section (no. 7)

Morphology of a flowering plant

Morphology of a winter twig

Anatomy of a tree trunk

Organization of primary tissues in young stems

Leaves

A. Anatomy1. palisade mesophyll 5.

stomata

2. spongy mesophyll 6. xylem

3. epidermis 7. phloem

4. cuticle

B. In lab:1. Ligustrum - leaf section (no. 8)

Leaf anatomy

Simple versus compound leaves

a. Simpleb. Compound

i. palmateii. pinnate

RootsA. Anatomy

1.epidermis 5. casparian strip2.cortex 6. pericycle3.stele 7. xylem4.endodermis 8. phloem

B. In lab:1.Ranunculus - root (no. 9)2.Salix - branch root (no. 10)3.radish root hairs4.sweet potato demo - storage root5.carrot - root stores sugars

Primary growth of a root

Organization of primary tissues in young roots

The formation of lateral roots

Root hairs of a radish seedling

Storage organs

A. white potato demo - modified stem

B. green onion demo - leaves modified for storage

C. celery - leaf petiole modified

D. sweet potato demo - storage root

E. carrot - root stores sugars

Principal Biological Concepts this lab:

A. Angiosperms as dominant plant taxon.B. Ovules enclosed within two integuments and a carpel

wall.C. Structure and function of flowers, and importance of

pollinators.D. Carpel wall may ripen as pericarp = fruit.E. Monocots versus dicotsF. Double fertilization.G. Plant tissues.H. Primary and secondary growth.I. Structure and function of shoots, roots, and leaves.

To study for next lab practical

• Moncots vs dicots• Flower parts• Leaf structures• Stem structures, xylem vs phloem,

monocots vs dicot vasculature• Root tissues & functions• Xylem vs phloem

Complete Plant Cladistic Exercise

A. Follow directions in Plant Cladistics data sheet (pp. 123-124).

B. Complete the cladogram and hand in before you leave.