Module 6 flowers.pptx
Transcript
MODULE 6: REPRODUCTIVE STRUCTURES Flowers Flowers • Flower parts are modified leaves (developed from a bud) • Reproductive organs Flower parts – sepals/calyx Flower parts – petals/corolla Flower parts • Perianth • Tepals – the corolla and calyx referred to collectively. – If the corolla...
MODULE 6: REPRODUCTIVE STRUCTURES Flowers Flowers • Flower parts are modified leaves (developed from a bud) • Reproductive organs Flower parts – sepals/calyx Flower parts – petals/corolla Flower parts • Perianth • Tepals – the corolla and calyx referred to collectively. – If the corolla and calyx look the same, they are all referred to as “tepals. Flower parts – stamens/androecium •Androecium – collective noun for all the stamens •Stamens made up of an anther and a filament Flower parts – carpels/gynoecium •Gynoecium – collective noun for all carpels •Pistils made up of stigma, style, and one to several carpels Ovary anatomy – placentation • Pattern of attachment of the ovule (what will become a seed) to the ovary • Carpel made of ovule plus locule (the chamber in which the ovule sits). • Ovule can be attached to the ovary in several ways, characteristic of plant species. Axile placentation • Ovules attached to the center, with carpels divided by walls (septa) Parietal placentation • Ovules attached to outer wall of ovary. Usually divided by septa. Free central placentation • Ovules all attached to a central column without septal divisions Basal, apical, and marginal placentation • Applies to ovary with a single (or few) ovules Basal – attached to base of ovary • Apical – attached to apex of ovary • Marginal – attached to margin of ovary • Connation and adnation • Patterns • Many • of attachment floral parts are fused together Connation - If parts from the same whorl are fused together. Petals to other petals to form a tube • Sepals to other sepals • Carpels fused together to form a compound ovary • Etc. • • Adnation – If parts from one whorl are fused to parts from another whorl Petals fused to sepals • Anthers fused to petals • Etc. • Connation Adnation (and connation too!) Flowers – ovary position •Also referred to by position of ovary – “superior” or “inferior” Flower symmetry - radial •Also known as actinomorphic symmetry Flower symmetry - bilateral •Also known as zygomorphic symmetry Flowers – complete/incomplete • Complete pistils flowers – flowers having sepals, petals, stamens, and • Incomplete flowers lack one or more of the above Flowers – perfect/imperfect • Perfect flowers contain both male and female parts • Imperfect flowers contain either male or female parts Flowers – monoecious/dioecious • Monoecious plants – have separate male and female flowers (imperfect, incomplete) on the same plant • Dioecious plants plants – have male and female flowers on separate • Hermaphroditic – plants with perfect flowers Spike Raceme Panicle Umbel Compound Umbel Head (Capitulum) Corymb Pollination • Flowers can be pollinated by a number of vectors Insects • Birds • Bats • Wind • Water • Self-pollination • Pollination - coevolution Pollination - coevolution Pollination - coevolution
