Introduction to the Angiosperms

Chapter 19 – Introduction to the Angiosperms I. Diversity in the Phylum Anthophyta II. The Flower a. The flower is a determinate shoot – that is, a shoot with the growth of a limited ruation, that bears sporophylls, which are sporangium-bearing leaves b. Carpel * Contains the ovules, which develop into seeds after fertilization * The Vessel c. Inflorescense * Flowers that may be clustered in various ways into aggregations d. Pedicel * The stalk of an individual flower in an inflorescense 1. The Flower Consists of Sterile and Fertile, or Reproductive, Parts Borne on the Receptacle a. Many flowers include two sets of sterile appendages, the sepals and petals, which are attached to the receptable below the fertile parts of the flower, the steamns and the carpels b. Sepals * Attached to the receptacle below the fertile parts of the flower c. Androecium * Microsporophylls * House of man d. Gynoecium * The carpels, house of women * Megasporophylls that are folwed lengthwise enclosing one or more ovules e. Stigma * Receives the pollen f. Ovary * Enclosed the ovules 2. The Ovules Are Attached to the Ovary Wall at the Placenta a. Placenta * The portion of the ovary where the ovules originate and to which they remain attached until maturity b. Placentation * The arrangement of the placentae * Consequently of the ovules varies among different groups of flowering plants 3. There Are Many Variations in Flower Structure a. Perfect- The majority of flowers include both stamens and carpels b. Imperfect - If either stamens or carpels are missing c. Staminate- Depending on the part that is present d. Carpellate e. Monoecious- If both staminate and carpellate flowers occur on the same plant as in maize and the oaks f. Dioecious * If the staminate and carpellate flowers are found on separate plants * As in the willows