Ch 29 Plant Diversity Learning objectives What did
Ch 29 – Plant Diversity
Learning objectives � What did plants evolve from? sets plants apart from other kingdoms? is the evolutionary sequence of the occurrence of seeds, vascular system, flowers, and the dominant stages in alternation of generations? � Be able to label the parts of the seed and flower. � What is double fertilization and which plants undergo double fertilization?
Plants evolved from a common ancestor of Charophytes
What are the differences between plants and their algae relatives (In other words, what are the derived traits of plants? ) Remember: These traits helped plants adapt to life out of the water
Walled spores (sporopollenin) � Sporopollenin is a tough polymer that keeps the plant from drying out.
Spores vs. Seeds SPORES � � � Usually haploid Smaller than a seed Usually single celled SEEDS � � � Have a supply of stored food Contains a zygote (fused sex cells) so is diploid Multicellular layers of tissue
Multicellular Gametangia �A specialized structure on the plant that produces gametes • Female gametangia: archegonia • Male gametangia: antheridia * The gametes will fuse to form an embryo (Key to the term embryophytes which defines plants)
Apical meristems � Area in roots and shoots where cells divide to elongate the roots and shoots. *Algae do not have true roots, leaves or shoots
Alternation of generations (Alternation between two generations of multicellular organisms)
Vocab for all plants Gametes • Male gamete • Female gamete � Gametangia • Archegonia • Antheridia � Gametophyte � Spores • Microspore • Megaspore � Sporocytes � Sporangia (sporangium) • Megasporangium • Microsporangium � Sporophyte
� Gametes – a haploid reproductive cell � • Male gamete - pollen or sperm • Female gamete - egg � � • Microspore – a spore that develops into a male gametophyte • Megaspore – a spore that develops into a female gametophyte Gametophyte – gamete producing plant Gametangia – multicellular organs that produce gametes • Archegonia – female gametanga • Antheridia – Male gametanga Spores – haploid cell that will give rise to a new organism � � Sporophyte - spore producing plant Sporangia – multicellular organs that produce the spores • Megasporangium – female sporangia • Microsporangium – male sporangia � Sporocytes – Cells that undergo meiosis to make spores
Vocab specific to moss � Gametophore
� Gametophore – gamete bearer
� Sporophylls – modified leaves that bear sporangia(spore producing organ) This includes sori in ferns, cones in gymnosperms and flowers in angiosperms
Vocab specific to ferns, gymnosperms and angiosperms � Sporophylls
Alternation of Generations ) Contain multicellular stages Is found in W ? (2 n or n is h ic h W ) Gametophytes Give rise to In moss the dominant stage is In gymnosperms the dominant stage is In ferns the dominant stage is Which is (2 n or n? ) In angiosperms the dominant stage is h hic is (2 n o ? rn Sporophytes Give rise to Which is (2 n or n? )
Sporophyte Moss Fern Gymnosperm Angiosperm Gametophyte
Sporophyte Gametophyte Moss The small structure that contains the sporangium Gametophore (gamete bearer) – the main part of the moss Fern The main plant considered the fern Small structure that looks like a lilly pad Gymnosperm The tree The grown megaspore which is made up of two or three cells, and the developed microspore (pollen) that has developed into two cells Angiosperm The flower The female gametophyte is everything within the megasporangium, the male gametophyte is the two cells within the pollen grain
Sequence of evolution of plants
Non-Vascular plants (Bryophytes) Traits � Multicellular embryo (all plants, not algae) � Non – vascular • This requires them to be small • Vascular plants have cells that are joined to produce tubes that transport water and nutrients � Live in damp/moist conditions so sperm can be transferred to the egg Examples: Liverworts, hornworts and mosses
Gametophyte life cycle is dominant
Seedless vascular plants Traits � Vascular tissue (allows them to grow taller) • Xylem: transport water and minerals • Phloem: transports sugar and amino acids (sap) � Use water to transport sperm to egg � Has true roots and leaves Ex. Lycophytes and Pterophytes
Sporophyte life cycle is dominant
Vascular, Seed Plants ANGIOSPERMS � A flowering plant, which forms seeds inside a protective chamber called an ovary. GYMNOSPERMS � A vascular plant that bears naked seeds – seeds not enclosed in specialized chambers
Seed bearing gymnosperms (conifers) plant reproduction � Fig 30. 6
Seed bearing angiosperm (flowering plant) reproduction � Fig 30. 10 � Dissect the flower � Label the parts
Seed plant fertilization
Monocots vs. Eudocots �In your notes, list the main characteristics of each (pg 631) and then take a corn seed and a green bean seed. You must determine which is a monocot and which is a eudocot
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