Chapter 24 Part 1 .pdf

Chapter 24 Seeded Plants: Gymnosperms (Part 1) Gymno= naked & seeds Adaptations needed to live in a terrestrial environment? Ways to obtain nutrients in water? ○ Stay close to water or develop vascular tissue Ways to keep water and stop desiccation? ○ Waxy cuticles on all surfaces keep water inside...

Chapter 24 Seeded Plants: Gymnosperms (Part 1) Gymno= naked & seeds Adaptations needed to live in a terrestrial environment? Ways to obtain nutrients in water? ○ Stay close to water or develop vascular tissue Ways to keep water and stop desiccation? ○ Waxy cuticles on all surfaces keep water inside Ways to get enough but not too much sunlight? ○ Develop habitat appropriate interception structure (leaves) and ways to mitigate sunburns Ways to get carbon dioxide and release oxygen? ○ Adaptive structures for gas exchange (Stomata, lenticel, etc.) Ways to structurally support the body? ○ Develop cell and body architecture that is strong enough to grow for competition of resources and withstand winds Ways to protect and spread offspring? ○ Develop embryo protection strategies ( fruit nuts eggs) The structure is provide protection and minimal nutrients until germination ○ Develop strategies for embryo dispersal Why did seeds give to our plants that spores didn't? ○ These plants still have spores they still use micro and megaspores but now what we've done is created a seed whether it is any naked seed like a gymnosperm or a vessel seed like an angiosperm. The seed is basically an immature Sporophyte That is housed in a protective shell of some sort and there is a food Reserve in that seed. Gymnosperms dominate during the Trassica~200-250 mya First seed plants are like fern-like in appearance: ○ Pteridosperms (seed ferns)- Reclassified as Gymnosperms Gymnosperms Characteristics ○ Sporophyte Dominant ○ Heterosporous; dioecious gametophyte ○ Megaphylls (Only microphyll is Lycopodiophyta) ○ Small taxa: 4 phyla w/ 73 genera and 700 species ○ Phyla Coniferophyta-Conifers Non-motile sperm Mostly evergreen Monoecious sporophyte Largest unit Has tracheids but not vessels elements Most have needle-like leaves ○ Fascicle bundle Ethnobotanical ○ Masts (telephone pole) ○ Wood ○ Turpentine ○ “Pokewood” ○ Pine needle tea- very rich in vitamin C (not enough orange juice) ○ Fuel ○ Perfume ○ Lumber ○ Crates, furniture Cycadophyta- Cycads Dioecious sporophyte Tracheids Evergreen; typically see in tropical or subtropical areas Motile (many flagella) Ethnobotanical; ○ Horticulture uses Ginkgophyta- Ginkgo Biloba (single extant species) Maidenhair fern Dioecious sporophyte Single extant species ( means still here); Ginkgo biloba Leaves; fan shaped Braching; dichotomously Deciduous Fall; bright and gold can get large Sperm; motile vestillget Odiferous seeds Tracheids Ethnobotanical ○ Horticulture ○ Urban areas (in air pollution) ○ Take extract for bring down blood pressure ○ Can eat seeds- some culture Gnetophyta- Gnetophytes Tracheid & vessel elements Dioecious sporophyte Morphologically diverse Deciduous Non-motile sperm Gnetum- Vine-like plants with broad leaves in tropics Joint Firs (Ephedra); shrubby plants of drier regions of southwestern North America Ethnobotanical ○ Drug extracts; ephedrine for respiratory problems from a chinese species ○ Weight loss ○ Horticulturally Gametophyte Stage becomes REDUCED Vascular Tissue (Xylem and Phloem) ○ Gymnosperms xylem: Tracheids (all 4 phyla) Vessel elements (Gnetophyta) ○ Wood (secondary xylem); (Secondary vascular tissue; some not all) Manoxylic: soft and loose with high parenchyma cells- Cycads Pycnoxylic: high xylem, stronger Conifers and Angiosperms Pollen (stiminate) cones (male cones; male strobili) house the microspores that grow into pollen grains (male gametophyte) that can mature and send sperm to female gametophyte Female (ovulate) cones (strobili) I produce the megaspores that will grow into the female gametophyte that produces the archegonia and ovule that will be fertilized and become a seed. Seed Plant Classification (Superdivision; Superphylum) ○ Superdivision: Spermatophyta (Tracheophyta) Phylum Coniferophyta (Pinophyta)- Conifers Phylum Ginkgophyta- Ginkgo Biloba Phylum Cycadophyta- Cycads Phylum Gnetophyta- Gnetophytes Part 2- Coniferophyta Phylum Coniferophyta- Conifers Pines (Pinus sp.- largest genus) ○ Needle- like leaves ○ Mostly Monoecious Include world’s oldest known living organisms- Bristlecone pines Image Below (left)- 3 Needles and two vascular bundle IMPORTANT Female Conifers- NC NATIVE: Bald Cypress ( Taxodium distichum ○ deciduous= looses needles in winter (bright red, orange) Longleaf Pine (Predominant) -(Pinus palustris) SUPER THICK bark can withstand fires Loblolly Pine (Pinus taeda) Eastern Red Cedar (Juniperus virginiana) Frasier Fir (abies fraseri)