KINGDOM PLANTAE Multicellular eukaryotes autotrophs sporic meiosis life

KINGDOM PLANTAE Multicellular, eukaryotes, autotrophs, sporic meiosis life cycle

RESPONSES • TROPISMS • Plant growth response to a stimulus – 1. Positive – grows with/toward stimulus – 2. Negative – grows against/away from stimulus – 3. Phototropism – growth response to light – 4. Thigmotropism – growth response to touch – 5. Hydrotropism – growth response to water – 6. Geotropism/Gravitropism – growth response to gravity/Earth

RESPONSES cont… • Taxis/Nastic Response • Plant movement response to a stimulus – 1. Phototaxis – movement response to light • Ex. Helianthus annuus (sunflower) – 2. Thigmotaxis – movement response to touch • Ex. Dionaea muscipula (Venus fly trap)

Bryophytes Seedless Nonvascular • • Mosses Liverworts Hornworts Important Human Uses – Significant component of plant biodiversity (~16, 000 species) – Human uses Peat fuel & Peat Moss (used for heat/fuel)

Seedless Vascular Plants ferns & fern allies • A. Evolution of vascular plants – Cooksonia = oldest vascular plant fossil – Vascular Plant Body 1. Root System DERMAL – Anchor plant – Absorb water & nutrients 2. Shoot/Tissue System - leaves photosynthesis - stems elevate leaves - Tissue Systems – 1. Dermal » Outer protective covering – 2. Ground » Main plant body = storage – 3. Vascular » Conducts water & nutrients » Xylem = conducts water » Phloem = conducts minerals VASCULAR GROUND SHOOT SYSTEM ROOT SYSTEM

Ferns & fern allies PHYLUM PTEROPHYTA “ptero” = winged

BODY BLADE FROND PETIOLE RHIZOME ROOTS • • Lamina – blade Petiole - stalk Rachis - axis “fiddleheads” cercinate venation – Unrolling of the head; uncurls while it develops – Protects the delicate leaf tip

Order Filicales • Most ferns belong to this order • 10, 500 species • REPRODUCTION – Some have separate vegetative & fertile leaves – Sori = structures that hold spores – Multiflagellate sperm – Some only reproduce asexually

Conifers “gymnos” = naked GYMNOSPERMS - 1 ST PLANTS TO HAVE SEEDS “sperm” = seed

Reproduction • Male – Microsporangia make many spores • Microspores are the male gamete (sperm) • Female – Megasporangia make 4 megaspores • Megaspores are the female gamete (egg) • Fertilization – Fertilization of the egg produces a zygote (2 N) – Stores tissue inside the seed for food – Seed is dispersed

Fruiting plants ANGIOSPERMS

CARPEL Stigma Style Ovary stigma style anther petals sepals filament ovary Receptacle stalk STAMEN Anther Filament

Monocots • Parallel venation • Multiples of 3

(eu)dicots • Palmate venation • Multiples of 4 or 5

Fertilization & Fruits • Fruit Development • Double Fertilization – Ovule • 2 sperm fuse with the • Develops into seed (2 N) same egg – Integument = seed coat • 1 ST sperm + egg/N = – Endosperm = food reserve zygote (2 N) – Ovary • Develops into fruit • 2 ND sperm + egg/2 N = • Fruit completely encloses seed endosperm (3 N) • Fruit is a food source/reward for animals/transportation/disper sal

Outcrossing/Cross Pollinating Phases Dichogamy • Male & female parts are mature at the same time • a. Staminate (male dominant) • Male & female parts mature at different times • A. Protandrous – Carpels reflexed/bent to one side – Stamens produce pollen • B. Carpellate (female dominant) – Carpels swing up above – Stigma opens to receive pollen – “andro” = male – Stamens & anthers mature 1 ST • B. Protogynous – “gyno” = female – Carpels & stigmas mature 1 ST

Adaptations of species with bisexual flowers (aka “perfect flowers”) • Physical separation between the male & female parts • Self-incompatibility – Pollen from the same flower will not be able to fuse with the egg to germinate and produce any seeds. • e. g. Plums – must have 2 different varieties to get fruit!

Adaptations of species with Unisexual Flowers Monoecious Dioecious • “mono” = one • Male and female flowers are separate, but on the same plant • “di” = two • Male and female flowers are on completely different plants! • Guarantees outcrossing

Inbreeding (self-pollination) • About ½ of species in the temperate zones selfpollinate • Usually have small less-conspicuous(showy) flowers • Advantages – 1. saves energy • Can produce more seeds instead of colors, different maturation times, etc. – 2. genotype suited to a specific habitat • “if it ain’t broke… don’t fix it!” – 3. lack of pollinators • Cold environment not many birds/insects/animals

Families of Flowering plants

Daisies biggest eudicot family FAMILY ASTERACEAE 22, 000 species

Structure • Tiny flowers arranged into a huge compound head • “capitulum” – compound head of many smaller flowers • Fused anthers with a stigma sticking out the top • 2 fused carpels make up the inferior ovary • 5 fused stamens • 5 fused petals

Ray Flower Disk Flower

CAPITULUM Ray Flower Disk Flower Peduncle

Examples • Dandelions – Have only ray flowers • Thistles – Have only disk flowers • Sunflowers – Have both disk & ray flowers

Orchids biggest monocot family FAMILY ORCHIDACEA 24, 000 species

Structure • Stamen fused with style and stigma to form a column

Plant Pollinators Beetle-Pollinated Bee-Pollinated • Dull colors • Bright showy petals (blue & yellow) • Distinctive markings • Strong fragrances • Landing platform • Nectaries at the base of a corolla tube – (white/cream/green/darker) • Strong odors – (fruity/spicy/foul) • Inferior ovary to protect ovules • Edible parts

Plant Pollinators Cont… Butterfly Pollinated Moth Pollinated • Long tube with nectar at the bottom (specific to mouth parts) • Showy colors (red & orange) • weak fragrances • Open at night • Emit fragrance after sunset • Long tube with nectar at the bottom (specific to mouth parts) • White or pale colors

Plant Pollinators Cont… Bird Bat • Often red (visible to birds) • Usually odorless • Large amount of thin nectar (high energy) • Dull colors • Strong odors (fruity or musty) • Some open only at night • Large amount of nectar

Plant Pollinators Cont… Wind • Dull or colorless • Petals small or absent • Odorless and no nectar

PLANT HORMONES -Small organic molecules -Highly specific chemical agents -Only produce certain results -Function in tiny concentrations -A little goes a long way -Regulate growth & development

Auxins Cytokinins • Produced in the shoot tips • Stimulate cell elongation Auxin production (NOT DIVISION) • Only moves down through plant • Indolacetic Acid (IAA) • Produced in the root tips • Stimulates cell division • Only moves up through the plant – Most common natural auxin – Important in fruit growth Cytokinin production

Ethylene • Only gas hormone in plants • Inhibits cell expansion • Promotes fruit ripening – Change in color – softening • Promotes leaf drop

extras Abscisic Acid Gibberellins • Inhibitors • Restrains plant growth • Promotes growth – Cell division & elongation • Promotes seed germination – Fertilized seed can start to grow