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An ovule of a seed plant consists of the megasporangium, megaspores, and integuments †¢Explain why pollen grains were an important adaptation for successful reproduction on land. Pollen grains were an important adaptation because the evolution of pollen allowed for pollination and contributed to the diversity of seed plants Basically like pollen allowed for sexual reproduction so there could be diversity †¢Explain how a seed can be said to include contributions from three distinct generations. 1) Seeds can survive harsh conditions through dormancy ) Distributed far from their parent sporophyte (or close depending) 3) Multicellular. Concept 30. 2: Gymnosperms bear â€Å"naked† seeds, typically on cones †¢List and distinguish the four phyla of gymnosperms. 1) Phylum Ginkgophyta Phylum Ginkgophyta consists of only a single extant species, Ginkgo biloba This popular ornamental species has fanlike leaves that turn gold before they fall off in the autumn. 2) Cycadophy ta Cycads (phylum Cycadophyta) have large cones and palm like leaves. Cycads flourished in the Mesozoic era. We will write a custom essay sample on Test or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page (look like palms with cone) 3) Phylum Gnetophyta Phylum Gnetophyta consists of three very different genera. Weltwitschia plants have strap like leaves that are among the largest known leaves. (desert plant that looks like dried sea weed) Gentum species are tropical trees or vines. Ephedra is a shrub of the American deserts. (look like Welt but have little cones) 4) Coniferophyta The conifers belong to the largest gymnosperm phylum, the phylum Coniferophyta. The term conifer comes from the reproductive structure, the cone, which is a cluster of scale like sporophylls. (large trees, juniper berries, pines, sequoia) Describe the life history of a pine. Indicate which structures are part of the gametophyte generation and which are part of the sporophyte generation. †¢ oIn most conifer species, each tree has both ovulate and pollen cones. The pine tree is the sporophyte. Each ovulate cone contains megasporangium. Microsporangium undergoes meiosis, producing haploid micropsores that develop into pollen grains. A pollen grain enters through the micropyle and germinates, forming a pollen tube that digests through the megasporangium. By meiosis, four haploid cells are produced. One survives as a megaspore. Female egg develops. Fertilization occurs as sperm and egg nuclei unite. The ovule becomes a seed. oWhich does not apply to gymnosperms or angiosperms? 1. Vascular tissues 2. Diploid dominance 3. Single spore type (because they have micro- and megaspores) 4. Cuticle with stomata oIn seed bearing plants, microspores develop into ____. 1. Ovules 2. Seeds 3. Pollen grains 4. Anthers o oHow many generations are represented in the seed of a gymnosperm? 1. 1 2. 2 3. 3 4. 4 oGymnosperms include 1. Gingko biloba, conifers, and flowering plants 2. Pine trees, apple trees, and rose bushes 3. Conifers, cycads, and magnolia 4. Cycads, conifers, Gingko biloba, and gnetophytes o Concept 30. 3: The reproductive adaptations of angiosperms include flowers and fruits †¢Identify the following floral structures and describe a function for each: oSepal †¢modified leaf in angiosperms that helps enclose and protect a flower bud before it opens oPetal †¢modified leaf of a flowering plant that advertise insects and other pollinators oStamen †¢pollen-producing reproductive organ of a flower , Contains: †¢Filament ostalk of a stamen †¢Anther in an angiosperm, the terminal pollen sac of a stamen, where pollen grains with male gametes form oCarpel †¢ovule-producing reproductive organ of flower , contains: †¢Stigma osticky part of a flower’s carpel, which traps pollen grains †¢Style othe stalk of a flower’s carpel, with the ovary at the base and the stigma at top †¢Ovary oin flowers, the portion of a carpel in which the egg-containing ovules develop †¢Ovule oa structure that develops within the ovary of a seed plant and contains the females gametophyte †¢Define fruit. Explain how fruits may be adapted to disperse seeds. A fruit is a mature ovary of a flower that protects dormant seeds and aids in their dispersal. Some fruits are dispersed by wind, others, such as coconuts, by water. Many rely on animals to carry the seeds by clinging to fur or producing edible fruits so that by the time the seed is deposited from the animal tract, the seed is far from the parental sporophyte. †¢Diagram the generalized life cycle of an angiosperm. Indicate which structures are part of the gametophyte generation and which are part of the sporophyte generation. †¢Explain the process and function of double fertilization. Double fertilization is a mechanism of fertilization in angiosperm in which two sperm cells unite with two cells in embryo sac to form the zygote and endosperm. One hypothesis for the function of double fertilization is that it synchronizes the development of food storage in the seed with development of the embryo. †¢Distinguish between monocots and eudicots. oMonocots is a clade consisti ng of flowering plants that have one cotyledon while oEudicots is a clade consisting of a vast majority of flowering plants that have two cotyledons. oOne difference between gymnosperms and angiosperms is that 1. Only angiosperms reproduce sexually 2. Only angiosperms produce fruits 3. Only angiosperms produce seeds 4. Only angiosperms produce wood oIf an angiosperm plant embryo contains two seed leaves, the plant is a ____. 1. Monocot 2. Eudicot 3. Bryophyte 4. Conifer oGymnosperms and angiosperms have the following traits in common except ____. 1. Seeds 2. Pollen 3. Vascular tissue 4. Ovaries 5. Ovules oWith respect to angiosperms, which of the following is incorrectly paired with its chromosome count? 1. Egg cell – n 2. Megaspore – 2n 3. Microsporocyte – 2n 4. Endosperm – 3n