Flower morphology

“Complete” FLOWER

Carpel

Complete flower (hermaphrodite)

Calyx (K)Corolla (C)

Androecium (A)

Gynoecium (G)

Flower diagram

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:

Calyx tube

Calyx lobes

Silene spp.

Fabaceae flower

Gamosepalous

Rosa spp.

Aposepalous

Calyx with free sepals

Stellaria media -chickweed

Oenothera spp.

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

عروسک پشت پردهPhysalis

مهمیز

The corolla (C): Totality of petals in the flower

Corolla with free petals

Papaver spp.Ranunculus spp.

Polypetalous or Apopetalous

Corolla with connate (united) petals

Corolla tube

Corolla lobesDigitalis spp.

Campanula spp.

Sympetalous or Gamopetalous

Types of corolla with connate petals

Bell-shaped

Campanula spp

Funnelform

Petunia spp.Salveform

Syringa vulgaris

Tubular Helianthus spp.Ligulate Helinthus 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 ArrangementsMagnolias have dozens of stamens Some have free stamens and

others are fused at filaments

• Some flowering plants are neither monocots or dicots.

• Magnolia

ماگنولیا

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 [♂]

“normal” DidynamousMint family (Lamiaceae)

TetradynamousCabbage familyBrassicaceae

Monadelphous Malvaceae

Diadelphous: many Fabaceae

Monadelphousیک دسته پرچمی

Polyadelphous چند دستهپرچمی

Syngenesiousپیوسته بساک

Diadelphous دو دسته پرچمی

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

Ovary

Carpel

Apocarpous versus syncarpousgynoecium

جدا برچه

پیوسته برچه

carpels

Apocarpus

[with free carpels]

Syncarpous

[with connate carpels]

تخمدان چندخانه ایPolylocular

تخمدان چندخانه ایPolylocular

تخمدان یک خانه

ای

Gynoecium (G): totality of carpels in the flower [♀]

Inferior ovary superior ovary

Depending on the position of the ovary in relation to the calyx and corolla:

hypanthium

گل زیرینHypogynous

گل میانیPerigynous

گل زبرینEpigynous

Ovary position

inferior hypanthium

superior

Male (staminate) & Female (pistillate) flowers

(incomplete)

Pistillate (female) flowers (cucumber)

Staminate (male) 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

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

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

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Floral Diagram Symbols I

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Floral Diagram Symbols II

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Sample floral diagrams

General Flower-termsPeduncle: 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 + corollaWhen 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.

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

• Has an elongated inflorescence on the main stem.

• Ex: liatris, gladiolus

Spike:

Types of Inflorescence

• Similar to a spike except florets aren’t directly attached to the stem

• Ex: delphinium

Raceme:

Types of Inflorescence

• Has a flat top or slightly convex shape

• Has main stem with pedicels of unequal length

• Ex: yarrow

Corymb:

Types of Inflorescence

• Broad and flat topped

• Has divisions that arise below a terminal flower

• Ex: Bird of Paradise

Cyme:

Types of Inflorescence

• 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

Umbel:

Types of Inflorescence

• Short, dense cluster of flowers in a flat pattern

• Ex: sunflowers

Head Flower:

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