Download presentation
Presentation is loading. Please wait.
1
Topic 9—Plant Biology Plant Diversity
2
Major Plant Groups Figure 22-6 p. 554 Flowering plants
Cone-bearing plants Ferns and their relatives Mosses and their relatives Green algae ancestor Flowers; Seeds Enclosed in Fruit Seeds Water-Conducting (Vascular) Tissue Figure 22-6 p. 554
3
The Diversity of Plants
Section 22-1 Cone-bearing plants 760 species Flowering plants 235,000 species Ferns and their relatives 11,000 species Mosses and their relatives 15,600 species Figure 22-7 p. 555
4
Success on land Avoid drying out with a outer waxy covering
Absorb, conduct and conserve water Reproduce without water… Spores and seeds
5
Alternation of Generations (p.552)
diploid, asexual stage haploid, sexual stage
7
Avascular, seedless plants
Mosses and liverworts
8
p. 558
9
Moss life cycle Gametophyte stage: (dominant) Sporophyte stage:
Protonema = tiny filaments producing leafy shoot Leafy shoot with rhizoids (rootlike structures) Archegonia = female organs producing eggs Antheridia = male organs producing sperm Sporophyte stage: Stalk & capsule (containing sporangia spores) Spores produce protonema
12
Vascular, seedless plants
Ferns and horsetails, etc.
13
Fern life cycle Sporophyte stage (dominant)
Fronds (leaves), rhizomes (underground stems) and roots ( with vascular tissue) Sori (under frond) contain sporangia spores Gametophyte stage = heart-shaped Prothallus sperm from antheridia swim to egg in archegonia producing zygote Zygote grows into young sporophyte
17
Vascular plants with seeds
Gymnosperms Exposed seeds Angiosperms Seeds enclosed in a fruit Flowering plants
18
Gymnosperms Means “naked” seeds…seeds are NOT enclosed in a fruit
Examples: cone-bearing plants, cycads, & gingkos
20
Sporophyte stage: pollen cone (male) microsporangium microspore
Consists of plant body containing roots, stems, & leaves pollen cone (male) microsporangium microspore seed cone (female) megasporangium megaspore 1st yr = pollination nd yr = seed developing rd yr = open to release seeds on scales
22
Gametophyte stage: Microspores pollen (male gametophytes) sperm
megaspores ovules (female gametophytes) eggs after fertilization, zygote begins seed, which develops into new sporophyte
23
Angiosperms Monocotyledons (one seed-leaf)
Examples = grasses, grains, orchid family, palms Dicotyledons (two seed-leaves) Examples = vegetables, nut & fruit trees, & all other flowers in the garden
24
Comparison of Monocots vs. Dicots
Seed : One seed leaf Two seed leaves Leaf : Parallel veins Branching veins Flower parts: Multiples of Multiples of 4 or 5 Root system: fibrous taproot Stem : random radial vascular bundles vascular bundles
25
Monocot Characteristics
26
Dicot Characteristics
28
Sporophyte stage Zygote Embryo (within seed) plant body
plant body consisting of roots, stems & leaves flower containing male & female reproductive organs reproductive organs microspores & megaspores
29
Gametophyte stage: Microspores pollen (male gametophyte containing sperm) Megaspores ovule (female gametophyte containing eggs) after pollination & fertilization… sperm + egg zygote (which begins the seed)
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.