2Basic structure of the angiosperm flower The fertilization processPollen and stigma self-incompatibilityThe efficiency of animal pollinationSome basic types of flowerReproduction and diversity of angiosperms
4Collective nouns that can cause confusion! CalyxThe outer whorl of a flower made up of sepals that are usually green, and protect the flower in bud.CarpelBears the stigma, and frequently an elongated style, and encloses the ovules (sometimes gynaecium). The megasporophyll of the flowerCorollaThe collective term for the petals of a flowerOvaryThe total of the carpels in a flower is the ovaryPistilEach separate carpel when there are lots of them in the ovaryPerianthThe floral envelope, it includes the calyx and corolla.StamenThe anther and its supporting filament. The microsporophyll of the flower
5Evolution of the pistil Ways in which Angiosperms are different from GymnospermsAngio-Gymno 4 Ovules protected within an enclosed structureEvolution of the pistil
12Ways in which Angiosperms are different from Gymnosperms Angio-Gymno 5. Double fertilization to produce diploid zygote and triploid endosperm nucleus
13What goes on in the endosperm? The triploid nucleus divides and the endosperm cell becomes a supercell with many nuclei and a milky consistency. Cyotkinesis forms membranes and walls between the nuclei and makes the endosperm more solid. The developing embryo uses the nutrients stored in the endosperm, as does the moncot seedling after germination. In most dicots, food reserves are moved to the cotyledons and the endosperm is not present in a mature seed.
14Somatic cell division involves two successive steps: mitosis and cytokinesis. In mitosis, the nuclear DNA duplicates and chromosomes segregates equally between the two daughter nuclei;cytokinesis divides these two nuclei and cytoplasm, including related cytoplasmic organelles, into two individual cells.
15Ways in which Angiosperms are different from Gymnosperms Angio-Gymno 5. Generally angiosperms have hermaphrodite flowers and cross pollinate (70%)
17Pollen and stigma incompatibility There can be dozens of alleles of the S-gene. If a pollen grain has an allele that matches an allele of the stigma upon which it lands, then the pollen tube fails to grow. What happens when pollen from plants with three different allele pairs is crossed with an S1S2 plant? This system prevents self-fertilization AND fertilization from close relatives.
18Rye grass incompatibility Pollen Grain Size and Surface Morphology in a Perennial Rye Grass HybridRye grass incompatibilityAttempts to hybridize between particular varieties resulted in production of a web-like substance and incompatibilityPollen grain on stigmaStacey Lacoste
19The efficiency of animal pollination Pollen is up to 30% proteinNucleus of tube cellAnimal pollination is targeted and so is more efficient than wind pollination.Generative cellAnimal pollinated flowers generally produce much less pollen than wind pollinated flowers.Pollen is important for animals – and many animal pollinated plants do produce excess pollen.Lilium pollen
20Some basic types of flower Separate petalsMagnolia grandiflora
21Flowers with a tubular corolla Gentiana algidaRocky Mountain National Park CO
23Monocotyledons Flower parts in threes Narcissus spp.
24Monoecious, wind pollinated Oaks, have separate male and female flowers.The female flower (upper left) consists only of carpels and a calyx (collection of sepals).The male flowers are in elongated clusters, called catkins, and consist only of anthers and a calyx. Both sexes are found on the same tree, and thus oaks are monoecious (meaning same house).Some trees, e.g., poplars and willows are dioecious (meaning two houses), and there are male and female trees.Other monoecious genera include birch, walnut, ash, hickory, and most maples.
25Reproduction and diversity of angiosperms Animal pollination is efficient and associated with the development of the hermaphrodite reproductive axisThe diversity of flowers represent mechanisms promoting efficient pollinationPrevention of self-fertilization maintains genetic variation by promoting cross pollinationSophistication of the reproductive process enables a large number of ways reproductive isolation can occur and so maintains genetic diversity
26Sections you need to have read through and and 31.10Courses that deal with this topicBotany 113 Plant identification and classification