Life 103 Exam 2 Lockwood CSU Questions And Answers With Complete Solutions 100% Correct Answers

Flowers - specialized structure for sexual reproduction, pollination by animals (insects, mammals, birds) and wind Seed - consists of an embryo and nutrients surrounded by a protective coat. Gametophytes of seed plants - develop within the walls of spores that are retained within tissues of the parent sporophyte The ancestors of seed plants were most likely_____, while seed plants are ________. - homosporous; heterosporous Ovule - consists of a megasporangium, megaspore, and one or more protective integuments (outside coating) Megasporangium (Gymnosperm Female Anatomy) - diploid tissue where haploid megaspore is formed (meiosis) Megaspore(Gymnosperm Female Anatomy) - haploid cell that grows into female gametophyte, including the egg nucleus Microsporangium(Gymnosperm Male Anatomy) - diploid tissue where haploid microspores are formed (meiosis) Microspores (Gymnosperm Male Anatomy) - develop into male gametophyte Pollen - contains the male gametophyte within the tough pollen wall. Structure influenced by dispersal methods, exterior composed largely of sporopolleninGymnosperm Fertilization - Pollen released into the air, pollen grain reaches ovule and germinates, pollen tube grows digesting through megasporangium, pollen tube reaches egg nucleus and discharges sperm nucleus into egg nucleus of female gametophyte Pollen Grains - developed from microspores, which contain the male gametophytes Pollination - is the transfer of pollen to the part of a seed plant containing the ovules Evolutionary Advantage of Seeds - A seed develops from the whole ovule, a seed is a sporophyte embryo, along with its food supply, packaged in a protective coat. A seed provides some evolutionary advantages over spores: they remain dormant for days to years, until conditions are favorable for germination. They maybe be transported long distances by wind or animals The gymnosperms have naked seeds not enclosed by ovaries and consist of what 4 phyla? - Cycadophyta (Cycads), Gingkophyta(one living species: Ginko boloba), Gnetophyta (Three genera Gnetum, Ephedra and Welwitschia), and Coniferophyta (conifers such as pine, fir and redwood) Phylum Cycadophyta - individuals have large cones and palm like leaves Phlum Ginkgophyta - phylum consists of a single living species, Ginkgo Biloba Phylum Gnetophyta - phylum comprised of three genera The Carpel - consists of an ovary at the base and a style leading up to a stigma, where pollen is received. The Female gametophyteor embryo sac - develops within an ovule contained within an ovary at the base of the stigma The Stamen - modified microsporophyll (sepals, pedals, stamen and carpels), male part of the flowerComplete Flower - has all modified leaves Incomplete flower - is missing one or more leaves Perfect Flowers - have both male and female parts Selfing Plants - Perfect flowers can theoretically self pollinate The Life of a Pollen - A pollen grain that has landed on a stigma germinates and the pollen tube of the male gametophyte grows down to the ovary, the ovule is entered by a pore called the micropyle. Double Fertilization occurs when the pollen tube discharges two sperm into the female gametophyte within an ovule. One sperm fertilizes the egg, while the other combines with two nuclei in the central cell of the female gametophyte and initiates development of food storing endosperm, the endosperm nourishes the developing embryo Cotyledons - one or two seed leaves that exist within a seed embryo Fruits - A fruit typically consists of a mature ovary but can also include other flower parts, fruits protect seeds and aid in their dispersal. Mature fruits can either be fleshy or dry Dry Fruits - Achene(dandelions, strawberries), Legume (pea, peanut, bean), Samara(maple, ash, elm), Nut(acorn, beech, hazelnut), Fibrous Drupe(coconut, walnut) Drupe - contains fleshy exocarp and mesocarp Influorescence (Multiple Fruits) - cluster of flowers, each flower becomes a fruit, all fruits merge into one mass What are the two main groups of angiosperms? - Monocots (one cotyledon) and eudicots ("true dicots")Basal Angiosperms - are less derived and include the flowering plants abelonging to the oldest lineages Magnoliids - share some traits with basal angiosperms but are more closely related to monocots and edicts. Include magnolias, laurels and black pepper plants. Flower parts come in multiples of 3 and often have parallel leaf veins