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Home , Connation, Floral diagram, Floral formula

CLASSIFICATION OF ORGANISMS Domain Archaea Prokaryotes, unicellular, absorptive nutrition, found in unusual habitats, high salt, excessive heat, for example; differ biochemically from the Bacteria Domain Bacteria

Prokaryotes, unicellular or in filaments, autotrophs and heterotrophs, sometimes called "true bacteria", diverse habitats Domain Eukarya Eukaryotes, unicellular & multicellular, four kingdoms: Protista, Fungi, Plantae, Animalia KINGDOM PROTISTA - eukaryotes (have true nuclei and membrane-bounded organelles), cell walls present in some; majority are motile; most unicellular, but some colonial & multicellular forms present; heterotrophs & autotrophs; sexual and asexual reproduction; majority are aquatic or in very moist terrestrial habitats. Heterotrophic Protists Phylum Myxomycota - plasmodial slime molds; multinucleate plasmodium and uninucleate ; nutrition by ingestion, terrestrial. Phylum Dictyosteliomycota - cellular slime molds; have two forms - one motile (amoeboid) and other non-motile (fruiting body); nutrition by ingestion, terrestrial. Phylum Oomycota - water molds; aquatic or terrestrial; motile. Autotrophic Protists ; Phylum Chrysophyta - chiysophytes or golden brown , unicellular or colonial, lack cell walls or have mineral walls or silica scales Phylum Bacillariophyta - diatoms, unicellular or colonial, silica cell walls, basis for aquatic food chains Phylum Euglenophyta - euglenoids; primarily freshwater organisms; no cell walls Phylum Dinophyta - dinoflagellates; also at base of food chains in aquatic ecosystems; red tide organisms. Phylum Rhodophyta - red algae; mostly marine; complex life cycles. Phylum Phaeophyta - brown algae; largest algae some with specialization; exclusively marine. Phylum Chlorophyta - green algae; probable ancestors of land ; few marine, but most primarily found in freshwater.

KINGDOM FUNGI - eukaryotes, most multicellular though few unicellular, majority are filamentous (mycelia); cell walls present; mostly non-motile; heterotrophs; no tissues or organs; sexual and asexual reproduction. Phylum Chytridiomycota - chytrids, aquatic with motile cells at some stage in life cycle Phylum Zygomycota - bread molds; dung fungi; Phylum Ascomycota - sac fungi; yeasts, cup fungi, morels; Phylum Basidiomycota - club fungi; mushrooms, puffballs, bracket fungi, rusts & smuts; KINGDOM PLANTAE - eukaryotes; multicellular photosynthetic organisms with rigid cell walls; only male gametes of some forms motile; tissues and organs present; autotrophs; sexual and asexual reproduction; vast majority are terrestrial. Non-Vascular Plants with Dominant Gametophvte. Reproduce by Phylum Hepatophyta - liverworts; multicellular gametangia, lack conducting tissues & stomata, simplest of land plants; have connection to algae at genetic level Phylum Anthocerophyta - hornworts, with basal , stomata, no conducting tissue Phylum Bryophvta - mosses; specialized conducting tissue in and sporophyte, stomata present.

Vascular Plants with Dominant Sporophyte, Reproduce fry Spores Phylum Psilotophyta - whisk ; no true or ; long evolutionary history. Phylum Lvcophyta - club mosses; true leaves and roots; Phylum Sphenophyta - horsetails and scouring rushes; whorled arrangement of roots, stems & leaves. Phylum Pterophyta - ferns; multiveined leaves with clustered sporangia (sori) on undersurface.

Vascular Plants with Dominant Sporophyte, Reproduce by Phylum Coniferophyta - conifers (cone-bearing); needlelike or scalelike leaves; exposed seeds; non-motile sperm. Phylum Cycadophyta - cycads; palmlike or femlike leaves; exposed seeds; motile sperm; formerly much more abundant. Phylum Ginkgophyta - Ginkgo biloba only remaining species; fan-shaped leaves;exposed seeds; motile sperm;"living fossils". Phylum Gnetophyta - gnetophytes; 3 very diverse genera; exposed seeds; non-motile sperm; some flowering properties. Phylum Anthophyta - flowering plants; seeds enclosed in a ; non-motile sperm; most diverse, widespread and successful of plant groups; have co-evolved with animals. Class Monocotyledones - monocots, one cotyledon in , parts in threes, veins parallel, true absent, vascular bundles in stem scattered. Class Eudicotyledones - dicots, two cotyledons in seed, flower parts in fours and fives, leaf veins netted, secondary growth present, vascular bundles in stem in ring.

HEPATOPHYTA ANTHOCEROPHYTA BRYOPHYTA (liverworts) (hornworts) (mosses)

GAMETOPHYTE - thailloid or leafy GAMETOPHYTE - thailloid GAMETOPHYTE - leafy - non-septate (no cross walls) Rhizoids - non-septate Rhizoids septate (cross walls) No leaves - dorsi-ventral flattened thallus Leaves - flattened when present, often bilobed in 2 or Leaves flattened; not bilobed, in spiral 3 rows without distinct raid vein arrangement with midvein Sex organs free, emergent Sex organs sunken in thallus Sex organs free Protonema rudimentary or none Protonema absent Protonema present SPOROPHYTE SPOROPHYTE SPOROPHYTE Seta clear or transparent No seta present Seta not clear, is opaque dehiscent by a lid or Capsule - not dehiscent or dehiscent by 4 valves; Capsule dehiscent by 2 valves longitudinal slits Columella absent Columella present Columella present in most No peristome teeth No peristome teeth Usually with peristome teeth Elaters present Elaters present No elaters Stomata absent Stomata present Stomata present Foot present Foot present Foot present Overall differentiation; no meristem Meristematic cells at apices Intercalary meristem between capsule and foot

ANGIOSPERMS: TERMINOLOGY Parts of the Flower Carpel: A leaflike structure that encloses one or more ; collectively, the . The carpel is the basic unit of the pistil; a simple pistil consists of a single carpel, and a compound pistil consists of two or more united carpels. Commonly differentiated into , style, and . Locule: A cavity within a sporangium or a cavity of the ovary in which ovules occur. Ovary: Swollen basal portion of the carpel or pistil containing (s). : The stalk of an individual flower in an .

Peduncle: The stalk of a solitary flower or of an inflorescence. : The and together. : The part of the flower that is usually conspicuously colored; collectively, the corolla. : The enlarged end of the flower stalk to which the sepals, petals, , and carpels are attached. : The outermost part of a flower; collectively, the calyx, which usually encloses the other parts. : The part of the flower that produces the ; usually composed of anther and filament; collectively, the androecium. Stigma: Upper, pollen-receptive portion of style. Style: Slender, stalklike portion of a carpel, or pistil; arises from the top of the ovary. Complete flower: A flower in which all four floral parts—sepal, petal, stamen, and carpel—are present. Incomplete flower: A flower in which one or more of the four floral parts is lacking. -merous: An ending that, together with a number, indicates the number of each of the floral parts. For example, 3-merous would mean having three parts of each kind. a-: A prefix used to indicate absence of a floral part (“apetalous” means that petals are lacking).

Distribution of Sexes Perfect flower: A single flower that has both stamens and pistils; bisexual, or hermaphroditic. Imperfect flower: A flower in which either stamens or pistils are lacking; unisexual. A unisexual flower possessing only an androecium is referred to as a staminate flower; a flower possessing only a gynoecium is referred to as a pistillate, or carpellate, flower. Monoecious: Having both carpellate and staminate flowers on the same plant. Dioecious: Having carpellate flowers on one plant, and staminate flowers on another of the same species.

Arrangement of Floral Parts Spiral arrangement: Floral parts are arranged in a spiral on the floral axis, or receptacle. Whorled arrangement: Having the floral parts arranged in circles, or in whorls (in the same plane), on the floral axis, or receptacle.

SYMMETRY OF FLOWERS Regular: Corolla made up of similarly shaped petals that radiate from the center of the flower and that are equidistant from one another; actinomorphic, or radially symmetrical, flower. Irregular: Having one or more parts in at least one of different form from other parts of the same whorl; a flower that is bilaterally symmetrical, or zygomorphic.

MONOECIOUS VS DIOECIOUS

INSERTION OF FLORAL PARTS Insertion of Floral Parts Hypogyny: Floral organization in which the sepals, petals, and stamens are attached to the receptacle at the base of the ovary, which is superior (that is, free from the calyx). Perigyny: Floral organization in which the sepals, petals, and stamens are attached to the margin of a cup-shaped extension of the receptacle (the ). The ovary is free of surrounding parts and is superior. Epigyny: Floral organization in which the sepals, petals, and stamens apparently grow' from the top of the ovary, which is inferior (that is, completely or partially attached to the calyx). Note: both hypogynous and perigynous flowers have superior (S) ovaries; only epigynous flowers have inferior (I) ovaries.

PLACENTATION TYPE

Axile: Having placentae arranged around (or ovules borne upon) a central of tissue in an ovary with as many locules as there are carpels. Parietal: Having placentae borne upon the ovary wall or on an extension of it; the ovary is not divided into locules. Free central: Having placentae borne upon a central column of tissue not connected by partitions with the ovary wall. Basal: Having placentae at the very base of a unilocular ovary.

CONNATION VS ADNATION

ADNATION

CONNATION

Connation (coalescence): The union of like parts. When the parts are not joined, the prefix apo- (separate) may be used to describe the flower (for example, aposepalous means separate sepals). When the parts are joined, either syn- or sym- is used (for example, “synsepalous” and “sympetalous” mean united sepals and united petals, respectively). Adnation: The union of parts of two different whorls.

INFLORESENCES Determinate: An inflorescence in which the first flower forms at the tip of the axis, thus stopping terminal growth. Flowers below the first bud open later. Indeterminate: An inflorescence in which flowers open in succession, the lower or outermost ones opening first. Panicle: An indefinitely branching indeterminate inflorescence; essentially a compound or a corymb. Spike: An indeterminate inflorescence consisting of a central stalk (rachis) and sessile, or nearly sessile, flowers. Raceme: An indeterminate inflorescence consisting of a central stalk (rachis) and pediceled flowers. Cyme: A few-flowered, flattish, determinate inflorescence in which the central or terminal flower opens earliest. : An indeterminate inflorescence consisting of several pediceled flowers arising from the same level. Corymb: An indeterminate inflorescence consisting of a central stalk (rachis) and pediceled flowers along the sides of the stalk. The pedicels of the lower flowers are much longer than those of the upper ones, giving the inflorescence a rounded or flat appearance. Head: A compact, indeterminate inflorescence consisting of sessile, or nearly sessile, flowers closely attached to the top of an expanded stem. Catkin (ament): A spike with apetalous, unisexual (imperfect) flowers

FRUIT TYPES are formed when an ovary undergoes changes, becoming either drv and hardened or enlarged and fleshy. This maturation process is generally triggered by hormonal signals accompanying seed formation. The nature of the fruit in a particular plant will depend, to a large extent, on the nature of the ovary from which it develops. For example, the of the ovules carried in a particular ovary will determine the eventual placement of seeds within the fruit. Also, the number of locules in the ovary will be apparent in the fruit.There are several key features which are used to classify fruits. These include: 1. The composition of the fruit. A true fruit is one that forms from ovary tissue alone, while an accessory fruit is one that includes modified tissue of other floral parts (usually the receptacle). 2. The origin of the fruit. A simple fruit is one that forms from a single ovary; an aggregate fruit (e.g. the raspberry, the strawberry with its development from flower to fruit) forms from several ovaries of a multipistiliate flower; a multiple fruit (e.g. the pineapple) forms from the ovaries of several different flowers within an inflorescence. 3. The texture of the fruit. Some fruits are dry whereas others are fleshy.

I. Dry fruits

A. Indehiscent fruits (these are fruits which do not open at maturity)

1. Achene - a small, dry. hard, indehiscent fruit, one-seeded, nut-like, often mistaken for a seed. Examples: sunflower, lettuce, strawberry, buttercup.

2. Caryopsis (grain) - an achene in which the ovary wall and seed coat are inseparable. Examples: wheat, com.

3. Nut - a large, indehiscent achene, commonly one-seeded. Examples:

chestnut, acorn of oak.

4. Samara - a winged achene or nut. Examples: maple, elm, ash.

B. Dehiscent fruits (these are fruits which do open at maturity to shed their seeds) 1. Follicle - derived from one carpel, several seeded, opening along one side at maturity. Examples: milkweed, proboscidea. larkspur.

2. Legume - derived from one carpel, usually several-seeded, opening along two sides at maturity. Examples: bean, pea.

3. Capsule - developed from a pistil of two or more united carpels, each opening at maturity. Examples: lily, iris.

II. Fleshy or partly fleshy fruits

A. : ovary wail becomes fleshy throughout, one to many seeds. Examples: grape, eggplant, persimmon, tomato, carambola. kiwi fruit.

B. Pepo - an accessory berry, in which the ovary wall and floral tube are adherent, with a hard rind. Applied to fruits of the gourd family. Examples: cucumber (also cucumber in c.s.). squash, pumpkin, cantaloupe.

C. Hesperidium - a modified berry, in which the outer part of the ovary wall becomes leathery. Applied to fruits of the citrus family. Examples: grapefruit, lemon.

D. Drupe - a fruit from a single carpel, in which the outer wall of the ovary has become fleshy and the inner part stony at maturity. Often termed a "stone fruit". Examples: plum, peach, almond, cherry. E. Pome - an accessory fruit derived from a compound pistil of several carpets, parts of which are stony or membranous and parts of which are fleshy; the whole permanently enclosed in the fleshy floral tube or receptacle. Examples: pear, apple, quince, hawthorn. Examples of dry fruits

(1) Dehiscent Fruits. Fruits that split open at maturity. (a) Legume. Develops from a simple pistil; splits along two sutures into two valves. (b) Follicle. Develops from a simple pistil; splits along one suture. (c) Capsule. Develops from a compound pistil; method of dehiscence is variable.

(2) Indehiscent Fruits. Fruits that do not split open at maturity. (a) Grain, or Caryopsis. Small, one-seeded; the seed coat is fused to the pericarp over its entire surface. (b) Achene. Small, one-seeded; seed attached to the pericarp at one point only; the pericarp is readily separable from the seed coat. (c) Samara. A winged achene. (d) Nut. The pericarp is hard or stony throughout; usually develops from a compound pistil with only one functional carpel; generally, one-seeded; usually with an involucre. 2. Aggregate Fruits. Fruits composed of several to many small fruits (fruitlets), all of which originate from a single flower with many separate pistils. The fruitlets mature together as a single unit on a common receptacle together with any associated accessory structures; mostly fleshy. 3. Multiple Fruits. Fruits composed of the matured ovaries of an inflorescence together with any associated accessor}1' structures; the mature fruits form a single unit; mostly fleshy.

ROOT MODIFICATIONS

STEM MODIFICATIONS

LEAF MODIFICATIONS

MONOCT SEED

DICOT SEED

MONOCT STEM

MONOCOT STEM

MONOCOT

DICOT ROOT

DICOT ROOT

DICOT STEM

DICOT STEM

WOODEN STEM

DICOT AND MONOCOT LEAVES

ROOT ZONES

MONOCT DICOT HYDROPHYTES

XEROPHYTES

C3 VS C4 PLANTS

FUNGI

ASCOMYCOTA BASIDIOMYCOTA

ZYGOMYCOTA

CHYTRIDIAMYCOTA

PLANT LIFE CYCLES

Fertilization (syngamy) is the fusion of two haploid gametes (the sperm and the egg) to form a diploid (2n) zygote. This is how the chromosome number in a life cycle changes from haploid (n) to diploid (2n). The biflagellate sperm in the above illustration is characteristic of a moss. Human sperm have a single flagellum.

Mitosis is the division of a haploid (n) or diploid (2n) cell into two duplicate daughter cells. In a strict definition, mitosis (karyokinesis) refers to the division of a nucleus into two duplicate nuclei, each with identical sets of chromosomes. Cytoplasmic division or cytokinesis involves a cleavage furrow in animal cells and a cell plate in plant cells. An example of cell division in haploid cells is the male honey bee (drone bee) which develops from a haploid unfertilized egg.

Meiosis is a special kind of cell division in which the chromosome number is reduced in half. This is how the chromosome number in a life cycle changes from diploid (2n) to haploid (n). In humans, the only cells that undergo meiosis are egg mother cells (oöcytes) in the ovaries and sperm mother cells (spermatocytes) in the testes. Egg formation and sperm formation are referred to as oögenesis and spermatogenesis. In flowering plants, meiosis occurs in mother cells (megasporocytes) within the ovules of ovaries, and in mother cells (microsporocytes) within the anthers of stamens. In the first division (blue cells in above illustration), the homologous chromosome doublets separate from each other so they are no longer in pairs. In the second and final division the chromatids of each doubled chromosome separate from each other forming the haploid gametes. During the first and second divisions of meiosis nondisjunction can occur, as shown in the following illustration. In normal spermatogenesis, X-bearing and Y-bearing sperm are produced. If an X-bearing sperm unites with an X-bearing egg, the resulting zygote is female (XX). If a Y-bearing sperm unites with an X-bearing egg, the resulting zygote is male (XY). Sometimes the X and Y chromosomes do not separate properly during the first division (Anaphase I) or the second division (Anaphase II) during spermatogenesis, a phenomenon known as nondisjunction. Nondisjunction may result in sperm that carry an extra X or an extra Y chromosome, such as XX- bearing sperm, XY-bearing sperm and YY-bearing sperm. If these sperm unite with an X-bearing egg, the result could be XXX (triple-X syndrome), XXY (Klinefelter's syndrome) or XYY (XYY-syndrome). This is also one way that polyploidy is achieved in plants – not an uncommon phenomenon. Three major kinds of life cycles: Gametic, zygotic, and sporic A. Zygotic: An example of a generic fungal life cycle (zygotic): note the short single celled diploid stage and the more complex multicellular haploid stage. In some shrooms the diploid stage has never been seen. B. Some variations on the sporic life cycle, and some we will be studying: Algae Life cycle (isomorphic alternation of generations):

Note: In The Following Life Cycles, Everything Above The Red Line Is Diploid (2n) And Everything Below The Red Line Is Haploid (n) Moss Life Cycle: Dominant gametophyte, dependent sporophyte Moss Life Cycle. Mosses belong to the Division Bryophyta characterized by nonvascular plants with that develop within multicellular female sex organs called archegonia. The dominant (conspicuous) part of the life cycle is the haploid, leafy gametophyte. The diploid sporophyte consists of a sporangium-bearing stalk that grows directly out of the gametophyte. mother cells within the sporangium undergo meiosis, producing numerous haploid spores that fall to the ground like tiny particles of dust. Since the sporophyte is without , it is completely dependent on the autotrophic (photosynthetic) gametophyte for its water, minerals and carbohydrate nutrition. Consequently, the sporophyte of the moss is heterotrophic and parasitic on the gametophyte. Most moss are dioecious, with separate male and female individuals in the population. The gametophytes are produced by "male" and "female" spores. Mosses have a primitive method of fertilization that involves a motile, biflagellate sperm that swims through water to reach the egg on female plants.

Some lichens superficially resemble mosses from a distance, particularly fruticose (branched) lichens growing on the branches and trunks of . Lichens are essentially fungi containing symbiotic algal cells. The photosynthetic algae provide carbohydrate nutrition for the fungus, while the fungus provides a protective place for the algal cells to thrive in an otherwise hostile environment. Because the relationship or "marriage" is beneficial to both partners, this particular example of symbiosis is classified as mutualism. Life Cycle: dominant sporophyte: Fern Life Cycle. Ferns belong to the Division Pterophyta characterized by vascular plants with leaves (fronds) arising from subterranean, creeping . In ferns, the leaves are produced on a definite woody trunk. The dominant (conspicuous) part of the life cycle is the diploid, leaf-bearing sporophyte. On the underside of the leaves are rows of brown sori. Each sorus is composed of a cluster of sporangia, and is often covered by a thin outer layer called the indusium. Some ferns such as Polypodium and Cyrtomium do not have the indusium. Ferns are classified by the arrangement of the sori and shape of the indusium. The sori and indusium superficially resemble an infestation of scale insects, and some people actually spray their ferns! Spore mother cells within the sporangium undergo meiosis, producing numerous haploid spores. The sporangia split open at maturity, releasing millions of spores that fall to the ground like tiny particles of dust. The splitting open of a sporangium is caused by a thick-walled, outer belt of cells called the annulus. As the cells of the annulus dry out, the annulus contracts and rips open the sporangial wall, thus dispersing the spores.

Each spore germinates and grows into a heart-shaped gametohyte (prothallus) which is smaller than your little finger nail. This haploid gametophyte bears male and female sex organs (antheridia and archegonia). With respect to populations of gametophytes, ferns are typically monoecious with both male and female sex organs on the same gametophytes. Unlike the unisexual gametophytes of a moss, a fern gametophyte is bisexual. Like mosses, ferns have a primitive method of fertilization that involves a multiciliate sperm that swims through water to reach the egg. The gametophytes and of ferns are photosynthetic and autotrophic.

Flowering Plant Life Cycle Cycle. Flowering plants (angiosperms) belong to the division Anthophyta. Like ferns, the diploid sporophyte consists of a herbaceous or with roots, stems and leaves. Unlike ferns, flowering plants produce reproductive organs called flowers and seed-bearing fruits. The term angiosperm is derived from angio (vessel) and sperm (seed), referring to the seed-bearing vessels (containers) called fruits. Flowers may be unisexual or bisexual, depending on whether they contain only one type of sex organ (the male stamen or female pistil), or whether they contain both stamens and pistil in the same flower. Species with separate male and female flowers on the same plant are termed monoecious, including oaks (Quercus), alder (Alnus) and walnut (Juglans). Species with separate male and female flowers on separate individuals are termed dioecious, including willows (Salix), cottonwoods (Populus), date palms (Phoenix), some figs (Ficus) and marijuana (Cannabis). The following illustration shows a typical bisexual flower:

The general evolutionary trend is a gradual increase in the diploid sporophyte phase and a decrease in the gametophyte phase. In the moss, the diploid phase consists of a sporangium and stalk that grows out of the haploid female gametophyte. In the fern and flowering plant, the entire leaf-bearing plant is diploid. The haploid gametophye of a fern is reduced to a small, heart-shaped prothallus. In flowering plants, the haploid gametophyte is greatly reduced and consists of two microscopic structures: A seven-celled, eight -nucleate sac containing the egg and mother cell, and a pollen grain plus containing 3 nuclei, two of which are the sperm which penetrate the embryo sac during fertilization.

Asexual reproduction: Many species of plants reproduce asexually without gametes. They simply clone themselves by the formation of , , tubers, rhizomes, runners, turions, plantlets and "pups." In the duckweed family (Lemnaceae) daughter plants are produced vegetatively in budding pouches. Each "mother plant" produces up to a dozen daughter plants during its lifetime of 1-2 (or more) months. The daughter plants repeat the budding history of their clonal parents, resulting in exponential growth. It has been estimated that the Indian Wolffia microscopica may reproduce asexually by budding every 30 hours under optimal growing conditions. At the end of 4 months this would result in about 1 nonillion plants (1 followed by 30 zeros) occupying a total volume roughly equivalent to the planet earth. FLORAL FORMULAS

Floral formulas are useful tools for remembering characteristics of the various angiosperm families. Their construction requires careful observation of individual flowers and of variation among the flowers of the same or different individuals. The first symbol in a describes the symmetry of a flower.

(*) Radial symmetry – Divisible into equal halves by two or more planes of symmetry. (x) Bilateral symmetry – Divisible into equal halves by only one plane of symmetry. ($) Asymmetrical – Flower lacking a plane of symmetry, neither radial or bilateral.

The second major symbol in the floral formula is the number of sepals, with “K” representing “calyx”. Thus, K5 would mean a calyx of five sepals. The third symbol is the number of petals, with “C” representing “corolla”. Thus, C5 means a corolla of 5 petals. The fourth symbol in the floral formula is the number of stamens (androecial items), with “A” representing “androecium”. A∞ (the symbol for infinity) indicates numerous stamens and is used when stamens number more than twelve in a flower. A10 would indicate 10 stamens. The fifth symbol in a floral formula indicates the number of carpels, with “G” representing “gynoecium”. Thus, G10 would describe a gynoecium of ten carpels. Example: *, K5, C5, A∞, G10 Radial symmetry (*), 5 sepals in the calyx (K5) 5 petals in the corolla (C5) Numerous (12 or more) stamens (A∞) 10 carpels (G10)

Connation (like parts fused) is indicated by a circle around the number representing the parts involved. For example, in a flower with 5 stamens all fused (connate) by their filaments, the floral formula representation would be: A (5) The plus symbol (+) is used to indicate differentiation among the members of any floral part. For example, a flower with five large stamens alternating with five small ones would be recorded as: A5 + 5. Adnation (fusion of unlike parts) in indicated by a line connecting the numbers representing different floral parts. Thus, a flower that has 4 fused petals (connate corolla) with 2 stamens fused (or adnate) to this corolla, is described as: [C 4 , A 2] The presence of a hypanthium (flat, cuplike, or tubular structure on which the sepals, petals, and stamens are borne usually formed from the fused bases of the perianth parts and stamens) is indicated in the same fashion as adnation: X, [K 5, C 5, A 10], G 5 The lack of a particular floral part is indicated by placing a zero (0) in the appropriate position in the floral formula. For example, a carpellate flower (flower with a gynoecium but no functional androecium) would be described as: *, K3, C3, A0, G2 Flowers with a perianth of (no differentation between calyx and corolla) have the second and third symbols combined into one. A hyphen(-) is placed before and after the number in this symbol. Example: *, T-5-, A 10, G 3 A line below the carpel number indicates the superior position of the ovary with respect to other floral parts. G3

A line above the carpel number indicates the inferior position of the ovary with respect to other floral parts. ∞ (the symbol for infinity) indicates numerous floral parts and is used when the number is more than twelve in a flower. FLORAL DIAGRAMS Floral diagrams are stylized cross sections of flowers that represent the floral whorls as viewed from above. Rather like floral formulas, floral diagrams are used to show symmetry, numbers of parts, the relationships of the parts to one another, and degree of connation and/or adnation. Such diagrams cannot easily show ovary position.

How to Draw a

The floral diagram is always drawn circular in outline. The different floral whorls are represented in concentric circles, the sepals on the outermost circle, then the petals, the stamens and carpels towards the inner side.

The first step to draw a floral diagram is to examine mature floral which are due to open shortly but have not yet opened.

Pluck the floral bud from the mother axis only after you have noted down the anterior and posterior sides. Floral parts are drawn in a floral diagram as they would be seen in their transverse sections below the mother axis.

Make the floral diagram in the following sequential stages:

1. A very small circle is drawn above the floral diagram. This circle represents the mother axis. In actinomorphic flowers, the mother axis circle may be denoted as but in zygomorphic flowers it is drawn as. If the flowers are terminal, the mother axis is not drawn.

2. In bracteate flowers, a section of is drawn below the floral diagram. In flowers without any bract, such a section is not drawn.

3. In bracteolate flowers, bracteoles are drawn in section on the left and right sides of the diagram.

4. Note the number of sepals, their arrangement in relation to the mother axis and their aestivation. Draw transverse sections of sepals between the mother axis and the bract, keeping all these points in view. In case of odd number of sepals, the odd sepal would be drawn either posterior or anterior to the flower, i.e., opposite the mother axis or opposite the bract, respectively.

5. The same procedure is repeated for petals as for sepals. However, petals should be drawn alternate with the sepals.

6. If the flower is zygomorphic, petals are drawn of unequal sizes. Same may be the case with the sepals also in zygomorphic flowers.

7. If any sepal or petal is spurred, it is shown by drawing a loop at the back of that particular part in the floral diagram.

8. If parts of sepals or of petals are fused, draw lines to connect their edges together in the floral diagram.

9. In the epipetalous condition (i.e. when stamens are joined with petals), link the stamens and petals with small radial lines.

10. In case of bilabiate calyx or corolla, the two lips are joined by bulging lines.

11. Count the number of stamens, the number of whorls in which they are arranged, their cohesion and agnation to other floral parts, their position in relation to petals, their introse or extrose position, and draw them inside the petals in the floral diagram. Stamens are represented through transverse sections of the anthers. In the obdiplostemonous condition, the stamens of the outer whorl are drawn opposite to the petals. Introse stamens face towards the centre whereas the extrose towards the petals. are represented either by an asterisk (*) or by a cross (x).