C22 Test Review Study Guide Place these notes into your Biology Notebook A biennial is smaller during its first growing season. Unlike a dicot, a monocot has parallel leaf veins. The number of seed leaves distinguishes two classes of angiosperms. The specialized reproductive structure that evolved most recently is the ovary. There is evidence that Ginkgo biloba evolved before most other living species of seed plants. Seed-bearing plants differ from all other plants in that their gametes do not require water for fertilization to occur. When land environments became drier millions of years ago, many moss and fern species became extinct. The most ancient surviving seed plants are the gymnosperms. The evolution of seed plants caused many species of mosses and ferns to become extinct. The four groups of gymnosperms are conifers, cycads, ginkgoes, and gnetophytes. Conifers, cycads, gnetophytes, and ginkgoes have gymnosperms that produce exposed seeds. A plant is a multicellular eukaryote. Not all plants produce seeds. To produce spores plants must undergo meiosis. Plants use the energy of the sun to carry out photosynthesis. Plants get the water they need from the soil. The first plants evolved from an organism similar to multicellular green algae. Living on land required that plants conserve water. Bryophytes draw up water by osmosis; they lack vascular tissue. Mosses grow in low, shaded ground close to a water source. The rhizoid has a similar function as a root. In liverworts, the structures that produce eggs and sperm look like tiny green umbrellas. Mosses have long, thin cells called rhizoids that anchor them in the ground. The antheridium is the sperm-producing structure of the bryophyte. The immediate result of fertilization in mosses is a zygote. Vascular tissue includes xylem, phloem, and tracheids. Bryophytes do not have vascular tissue to carry water and nutrients. Ferns can thrive in areas with little light. Fern spores are diploid and are produced in sporangia. A seed includes a plant embryo, a food supply, and a protective covering. Club mosses are seedless vascular plants. Horsetails do NOT produce seeds. A fern life cycle is different from the moss life cycle in that a fern gametophyte always has both archegonia and antheridia.