Morphoanatomy of the Morphoanatomy of the FlowerFlower

Parts of a FlowerParts of a Flower

Pedicel -the stalk of an individual flower

Sepal --one member of the outermost whorl of a flower. Collectively, the sepals make up the calyx. The sepals may be free or fused.

PetalPetal --one member of the second whorl of a flower. --one member of the second whorl of a flower. Collectively, the petals make up the Collectively, the petals make up the corollacorolla. The . The petals may bepetals may be free free (the flower then termed (the flower then termed polypetalous) orpolypetalous) or fused fused into one piece (the flower then into one piece (the flower then termed sympetalous). termed sympetalous).

PerianthPerianth--the --the calyx and corolla calyx and corolla together together

CalyxCalyx

Corolla

StamenStamen--one --one member of the member of the whorl of male sex whorl of male sex parts. The part of parts. The part of the flower that the flower that produces pollen. produces pollen. This consists of This consists of two partstwo parts. The . The antheranther or top of the or top of the stamen actually stamen actually produces the produces the pollen. the anther is pollen. the anther is held aloft by a held aloft by a filament filament which is which is like a stem of the like a stem of the stamen. stamen.

Each Each stamenstamen consists of a consists of a filamentfilament and and antheranther, where pollen is produced. , where pollen is produced. Collectively, the stamens make up theCollectively, the stamens make up the androeciumandroecium androeciumandroecium

1. Tetradynamous

- refers to four long and two short stamens in one flower

Types of Stamens

2. Monadelphous----refers to stamens refers to stamens united by the united by the filaments into one filaments into one column column

3. Diadelphous--refers to stamens united by the filaments into two groups--often 1 in one group and 9 in another

Corydalis flavula

Desmodium laevigatum

CarpelCarpel

- one member of the whorl of female sex parts. - one member of the whorl of female sex parts.

- Collectively, the carpels make up the - Collectively, the carpels make up the gynoeciumgynoecium..

- Each carpel consists of an - Each carpel consists of an ovaryovary connected to a connected to a

sstigma by a by a stylestyle. .

- The stigma is receptive to pollen. Within the ovary, - The stigma is receptive to pollen. Within the ovary, on the placentae (sing.,on the placentae (sing., placentaplacenta) are one or more ) are one or more ovulesovules, which will mature into seeds. , which will mature into seeds.

- The open spaces inside the ovary are called - The open spaces inside the ovary are called loculeslocules or or cellscells. The dividing walls are called . The dividing walls are called septasepta. .

CarpelCarpel = inserted above the = inserted above the stamens,stamens,

= uppermost floral = uppermost floral organorgan

= consist of Stigma, = consist of Stigma, Style and PistilStyle and Pistil

which is which is collectively calledcollectively called

GynoeciumGynoecium

Stigma - Tip of the carpel, receptive toStigma - Tip of the carpel, receptive to

pollen pollen Ovary - Base of the carpel, contains OvulesOvary - Base of the carpel, contains Ovules Style - Connects the Stigma to the OvaryStyle - Connects the Stigma to the Ovary

Types of CarpelsTypes of Carpels

1. Apocarpous1. Apocarpous

- The flower is said - The flower is said to have many to have many simple simple pistilspistils

- A gynoecium of - A gynoecium of many separate carpels many separate carpels

Crassula

Magnolia

2. Syncarpous2. Syncarpous = A gynoecium of = A gynoecium of

many fused carpels many fused carpels = The flower is said = The flower is said

to have a to have a compound compound pistilpistil

Saxafraga

Poppy

3. monocarpous3. monocarpous

In the very center of the flower is a In the very center of the flower is a single single carpelcarpel. A carpel is the basic unit of a . A carpel is the basic unit of a gynoecium. gynoecium.

This flower only has This flower only has one carpelone carpel, and flowers , and flowers like this are said to have a like this are said to have a monocarpous monocarpous gynoeciumgynoecium. .

4. Unicarpellate

- - gynoecium gynoecium with only one with only one carpel carpel

- The flower - The flower has a has a simple simple pistilpistil

hypanthiumhypanthium

A hypanthium (= floral cup) is a structure derived by the adnation of the perianth bases and stamens. It can be variously shaped. This is a line drawing corresponding to a longitudinal section of a Prunus (cherry) flower.

Ovary PositionOvary Position

1. 1. HypogynousHypogynous--The --The flower is flower is hypogynous if the hypogynous if the ovary is situated ovary is situated above the calyx and above the calyx and there is no floral cup there is no floral cup around it. The ovary around it. The ovary is is superiorsuperior. .

2. 2. PerigynousPerigynous -The flower is -The flower is

perigynous if the perigynous if the ovary is situated ovary is situated within (and free within (and free from) a floral from) a floral cup or cup or hypanthiumhypanthium. . The ovary is The ovary is superiorsuperior. .

When the perianth and the stamens arise from a hypanthium that is NOT adnate to a superior ovary, the insertion is said to be perigynous, as in this longitudinal section of a flower of black cherry Prunus serotina.

3. 3. EpigynousEpigynous

--The flower is --The flower is epigynous if the ovary epigynous if the ovary is situated below the is situated below the calyx. The ovary iscalyx. The ovary is inferiorinferior. (In the . (In the graphic example, the graphic example, the calyx is pink and the calyx is pink and the flower hangs upside flower hangs upside down.) down.)

Inflorescence Inflorescence An inflorescence may be defined as a cluster

of flowers,all flowers arising from the main stem axis or peduncle::

cymecyme

Different types of inflorescencesDifferent types of inflorescences

A catkinA catkin

- a spike-like - a spike-like inflorescence (i.e. the inflorescence (i.e. the flowers do not have a flowers do not have a pedicel and the main axis pedicel and the main axis is elongated and is elongated and unbranched) which has unbranched) which has only male or female only male or female flowers. They occur in flowers. They occur in many woody trees such many woody trees such as the hazelnut and the as the hazelnut and the willow. willow.

A willow catkin (Salix sp)

Left: Male (staminate) catkin from the white mulberry (Morus alba), a fruitless variety commonly planted as a shade tree in southern California. Right: An individual male flower containing four stamens, each with an anther and a filament. At the base of each filament is a fleshy green sepal.

Female flowers consist of single pistil tightly enveloped by four inconspicuous sepals. Each carpel or pistil (also referred as a gynoecium) consists of a forked stigma, a short style and a spherical ovary. Each ovary (carpel) becomes a drupelet and the ripened cluster of drupelets (syncarp) is called a multiple fruit. In the aggregate fruit of a blackberry, all the drupelets of the cluster (syncarp) come from a single flower

Solitary

--just one flower on --just one flower on the peduncle the peduncle

SpadixSpadix - is the characteristic inflorescence of the - is the characteristic inflorescence of the

remarkable arum family (Araceae). remarkable arum family (Araceae). - It consists of a thickened, fleshy axis (spike) - It consists of a thickened, fleshy axis (spike)

bearing clusters of sessile, apetalous, unisexual bearing clusters of sessile, apetalous, unisexual flowers. flowers.

- The small unisexual flowers are packed together - The small unisexual flowers are packed together along the lower region of an erect, phallus-like along the lower region of an erect, phallus-like central spike, typically with male flowers above the central spike, typically with male flowers above the female. female.

- The upper region of the spadix is usually devoid - The upper region of the spadix is usually devoid of flowers. of flowers.

- Male (staminate) flowers consist of numerous - Male (staminate) flowers consist of numerous stamens packed together, stamens packed together,

- while female (pistillate) flowers consist of - while female (pistillate) flowers consist of numerous individual pistils. numerous individual pistils.

- Individual flowers are reduced to a - Individual flowers are reduced to a single stamen or pistil (gynoecium). single stamen or pistil (gynoecium).

- The spadix emerges from a vase-shaped - The spadix emerges from a vase-shaped or funnel-like modified leaf or spathe or funnel-like modified leaf or spathe which is often brightly colored. which is often brightly colored.

- The spadix of some arums emits a - The spadix of some arums emits a putrid odor that attracts carrion flies for putrid odor that attracts carrion flies for pollination. pollination.

The bizarre Malaysian Amorphophallus paeoniifolius. An enlarged, inflated, flower-bearing spadix protrudes from the vase-shaped spathe. Clusters of yellow male flowers (stamens) can be seen above the whitish stigmas of female flowers (pistils).

racemeraceme

- This - This inflorescence has inflorescence has an unbranched an unbranched main axis and all main axis and all the pedicels of the the pedicels of the flowers are more flowers are more or less the same or less the same length. length.

Other racemeOther raceme

Sweet pea (Lathyrus odoratus) Chinese hat (Holmskioldia sp.)

umbelumbel

- The peduncle of  this type of inflorescence - The peduncle of  this type of inflorescence bears all of the pedicels at its apex. bears all of the pedicels at its apex.

Hydrangea (Hydrangea macrophylla) Lantana (Lantana sp)

compound umbelcompound umbel - The peduncle - The peduncle

bears a number of bears a number of primary pedicels at primary pedicels at its apex. These do its apex. These do no bear flowers no bear flowers but a number of but a number of secondary pedicels secondary pedicels at their apices at their apices which in turn bear which in turn bear the flowers.  the flowers.  Frangipani (Plumeria rubra)

spikespike

- This - This inflorescence type inflorescence type has a long, has a long, unbranched main unbranched main axis which bears axis which bears flowers which flowers which have no pedicels have no pedicels or very short or very short pedicels. pedicels. Silver oak (Grevillea robusta)

Quiver tree (Aloe dichotma)

Quiver tree (Aloe dichotma)

Quiver tree (Aloe dichotma)

Quiver tree (Aloe dichotma)

Quiver tree (Aloe dichotma)

Gladiolus (Gladiolus sp.)

Red hot poker (Kniphofia sp.)

head (capitulum)

- which do not have pedicels

- are grouped together on the top of a peduncle which may be flattened or rounded.

- Daisies (Asteraceae) are a good example

- outer flowers may have one very large petal

- In other families the whole inflorescence may be surrounded by bracts e.g. the Proteas.

- This gives the impression that the whole structure is a single flower but it may in fact be hundreds of flowers grouped together.

Examples:

King protea (Protea cynaroides)

Daisy species

Mimosa sp. Pincushions (Leucospermum sp.)

A corymb A corymb

- The main axis of this - The main axis of this inflorescence type is inflorescence type is elongated and unbranched elongated and unbranched as in a raceme, but the as in a raceme, but the pedicels of the flowers are pedicels of the flowers are of unequal length so that of unequal length so that the entire structure appears the entire structure appears flat-topped. Examples flat-topped. Examples include hawthorn, the include hawthorn, the apple and dogwood. apple and dogwood.

Crataegus calpodendron

hawthornhawthorn

Hydrangea corymb (group of flowers displayed as a disc)

Difference of corycomb, cyme and Difference of corycomb, cyme and umbelumbel

SpikeletSpikelet

-like a spike, but with -like a spike, but with the flowers and the flowers and inflorescence inflorescence subtended by subtended by specialized bracts. specialized bracts. Usually applied to the Usually applied to the grass family (Poaceae) grass family (Poaceae)

Verticil or Whorl-Verticil or Whorl-

-the flowers are borne -the flowers are borne in a tight circle at in a tight circle at each node each node

PaniclePanicle

--the main axis has --the main axis has branches which are branches which are in turn rebranched in turn rebranched

Inflorescence Types Inflorescence Types

The EndThe End