Flower morphology

“Complete” FLOWER Carpel

Complete flower (hermaphrodite) Flower diagram Calyx (K) Corolla (C) Androecium (A) Gynoecium (G)

Bracts Definition --In botany, a bract is a modified or specialized leaf. Example: Euphorbia pulcherrima

Flowers without a calyx and corolla differentiated Perianth elements in this case are called tepals Petaloid tepals Sepaloid tepals

The calyx (K): Totality of sepals in the flower. Calyx with connate (united) sepals: Fabaceae flower Calyx lobes Calyx tube Gamosepalous Silene spp.

Aposepalous Calyx with free sepals Stellaria media -chickweed Rosa spp. Aposepalous Oenothera spp.

در برخی گیاهان با شکفته شدن گل کاسبرگ ها می افتد: خشخاش و شاه تره

عروسک پشت پرده Physalis

مهمیز

The corolla (C): Totality of petals in the flower Corolla with free petals Papaver spp. Ranunculus spp. Polypetalous or Apopetalous

Sympetalous or Gamopetalous Corolla with connate (united) petals Corolla tube Corolla lobes Digitalis spp. Campanula spp. Sympetalous or Gamopetalous

Types of corolla with connate petals Bell-shaped Campanula spp Funnelform Petunia spp. Salveform Syringa vulgaris Ligulate Helinthus spp. Tubular Helianthus spp.

Types of corolla with connate petals (continuation) Rotate – Solanum spp. bilabiate Lamium spp. Urceolate Vaccinium spp.

Types of corolla with free petals Papillonaceaous – Fabaceae (legume family)

Stamens

Stamen Arrangements Magnolias have dozens of stamens Some have free stamens and others are fused at filaments

ماگنولیا Some flowering plants are neither monocots or dicots. Magnolia

Orchids

Stamens continue In some specialized flowers the stamens are fused together. Form columnar structure i.e pea, melon and mallow fig 20-8d and sunflower 20-9d Some stamens fused with corolla i.e. snapdragon, phlox, and mint families.

Androecium (A): Totality of stamens in the flower [♂] Tetradynamous Cabbage family Brassicaceae Didynamous Mint family (Lamiaceae) “normal”

Diadelphous: many Fabaceae Monadelphous Malvaceae

Polyadelphous چند دسته پرچمی Diadelphous دو دسته پرچمی Monadelphous یک دسته پرچمی Syngenesious پیوسته بساک

Flower Anatomy

Double Fertilization Fertilization requires that pollen grains from anther to receptive stigma of a pistil Embryo sac forms with a stalk and 1 or 2 integuments that develop into seed coat Pollen reaches stigma and germinates to make pollen tube down style into the ovary pollen that forms the pollen tube is the tube cell 2nd cell in pollen grain is the generative cell as it divides and makes 2 sperm – move to a small opening in ovule called micropyle

The female parts of a flower The female part of the flower is made up of three main sections, the stigma, style and ovary. The receptive stigma serves as the “landing pad” for the male pollen. The style holds up the stigma and the ovary is the “house” for fertilisation and the seed. Together they are known as the Carpel Stigma Style Carpel Ovary

Apocarpous versus syncarpous gynoecium جدا برچه پیوسته برچه

تخمدان چندخانه ای Polylocular Apocarpus [with free carpels] carpels Syncarpous [with connate carpels] تخمدان چندخانه ای Polylocular

تخمدان یک خانه ای تخمدان چندخانه ای Polylocular

Gynoecium (G): totality of carpels in the flower [♀] Depending on the position of the ovary in relation to the calyx and corolla: hypanthium گل زبرین Epigynous گل میانی Perigynous گل زیرین Hypogynous Inferior ovary superior ovary

Ovary position inferior hypanthium superior

Male (staminate) & Female (pistillate) flowers (incomplete) Staminate (male) flowers (cucumber) Pistillate (female) flowers (cucumber)

Types of plants with unisexual flowers Dioecious: male and female flowers are separated on different individuals; e.g. Cannabis spp. Monoecious: male and female flowers are found on the same individual; e.g. Pinus spp.

Flower symmetry Zygomorphic .|. (bilateral) Actinomorphic (radial) *

Define the symmetry of these flowers * Convolvulus spp. .|. Lamium spp

Variation in Basic Parts Some flowers lack sepals, petals, stamens or pistils Grasses have 3 stamens, 1 functional carpel (may have 2 non-functioning ones), no petals or sepals Others have either stamens or carpels but not both

Floral Diagram Symbols I

Floral Diagram Symbols II

Sample floral diagrams

General Flower-terms Peduncle: The stalk of a flower. Receptacle: The part of a flower stalk where the parts of the flower are attached. Sepal: The outer parts of the flower (often green and leaf-like) that enclose the flower. Totality of sepals in a flower constitute the calyx. Petal: The parts of a flower that are often conspicuously colored. The totality of petals in a flower constitute the corolla. Perianth = calyx + corolla When the Sepals & Petals are identical, they are both called Tepals Androecium (male part): the totality of stamens in a flower. A stamen is formed from anther, which is supported by a slender filament. Anther: The part of the stamen where pollen is produced. Gynoecium (female part): totality of carpels in a flower. A carpel is formed from: ovary, style and stigma. The term Pistil has been used in the past to describe the gynoecium and this can cause some confusion in terminology Ovary: The enlarged basal portion of the carpels where ovules are produced. Stile: the part supporting the stigma. Stigma: The part where where pollen germinates. Monoecious: Male and female flowers on the same individual. Dioecious: Male and female flowers are separated on different individuals, which are therefore, male and female.

ALL botanical terms can be found online at: Symmetry terms Actinomorphic. Radially symmetric; divisible into two essentially equal portions along any median longitudinal plane. Zygomorphic: Bilaterally symmetric; divisible into two essentially equal portions along only one median longitudinal plane. Reminder Note: ALL botanical terms can be found online at: http://huntbot.andrew.cmu.edu/HIBD/Departments/DB-INTRO/IntroFNA.shtml

Monocot – Dicot: Comparisons

Types of Inflorescence Spike: Has an elongated inflorescence on the main stem. Ex: liatris, gladiolus

Types of Inflorescence Raceme: Similar to a spike except florets aren’t directly attached to the stem Ex: delphinium

Types of Inflorescence Corymb: Has a flat top or slightly convex shape Has main stem with pedicels of unequal length Ex: yarrow

Types of Inflorescence Cyme: Broad and flat topped Has divisions that arise below a terminal flower Ex: Bird of Paradise

Types of Inflorescence Umbel: Flower cluster that is easily recognized Simple umbel has single pedicelled flowers all arising from the top of the main stem. Ex: agapanthus Compound umbel has secondary umbels arising from main stem. Ex: Queen Anne’s Lace

Types of Inflorescence Head Flower: Short, dense cluster of flowers in a flat pattern Ex: sunflowers

Life Cycle Sperm is made in the pollen grain in the anther Egg made in embryo sac in the ovule Pollen grain and egg are gametophytes of flowering plants Zygote grows in ovule becomes first cell of new organism