FSc Notes Class XI Biology Plant Families

FSc Notes Class XI Biology Plant Families 1st Year Biology Notes Online Taleem Ilmi Hub Class 11

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 Plant Families

1- CAESAL PINIOIDEAE/CASIA FAMILY

CLASSIFICATION

DIVISION : ANGIOSPERMS

CLASS : DICOTYLEDON

SUBCLASS : POLYPETALAE

SERIES : CALCIFLORAE

ORDER : ROSALES

FAMILY : LEGUMINOSAE

SUB-FAMILY : CAESALPINIOIDEAE OR CAESALPINIACEAE.

GENERAL CHARACTERS

Majority of these plants are trees or shrubs, about 135 genera and 5800 species are known .

VEGETATIVE CHARACTERS

ROOT

Usually, Taproot with nodules and primary, secondary and tertiary divisions.

STEM

Usually, Climbing stem or erect herbaceous or woody, Some plants show xerophytic character.

LEAVES

Usually, Compound leaves bipinnate, stipulate.

INFLORESCENCE

Usually, Racemose.

FLORAL CHARACTER

Usually, Complete, bisexual, perigynous, zygomorphic, pentamerous.

CALYX

5 sepals, polysepalous, imbricate or valvate, Green in colour.

COROLLA

5 petals, poly petalous, imbricate aestivation.

ANDROECIUM

Usually, 10 stamens, polyanderous, exerted, extrose.

GYNOECIUM

Usually Monocarpillary, perigynous, placentational marginal, unilocular with many ovules.

FLORAL FORMULA

+ , Q , K(5) , C(5) , A10 , G1/

POLLINATION

Usually, Cross pollination by insects (entomophilly)

SEEDS

Usually, Both endospermic and non-endospermic.

FRUIT

Legume pod.

ECONOMICAL IMPORTANCE

MEDICINAL PLANS

  • Amaltas
  • Kachnar
  • Tamarindus Indica
  • Panwar. e.t.c.
  • ORNAMENTALS
  • Parkinsonia
  • Gul-e-mohar
  • Cacia sophera

DYES AND STAINING

Haemotoxylin is obtained from haemotoxylon campechianom.

EDIBLE FRUIT

Lomentum (Imli)

FIBER

Suitable fiber for paper making is obtained from parkinsonia Aculeata.

FAMILIAR PLANTS

Botanical name…………Common Name……………Local Names

1-Tamarindus indica………Tamarind……………..Imli

2-Cassia fistula…………Amaltus.

3-Bauninia verigata………Camel’s foot………….Kachnar

4-Poinciana regia………..Flame of Forest ………Gul-e-Mohar

5-Parkinosia roxburgai……VilayatiKikar


2 MIMOSACEAE

ALTERNATE NAME

It is also known as “Acacia family”.

CLASSIFICATION

DIVISION : ANGIOSPERMS

CLASS : DICOTYLEDON

SUBCLASS: POLYPETALAE

SERIES : CALCIFLORAE

ORDER : ROSALES

FAMILY : LEGUMINOSAE

SUBFAMILY : MIMOSACEAE / ACACIA

GENERAL CHARACTERS

It is the smallest group among the 3 groups of family legume. It contains about 40 genera and 1450 species.

HABITAT

Mostly plants are distributed in tropical and subtropical regions. Great variation inhabit, usually these trees are perinial or binnial shrubs, some are herbs and climbing.

VEGETATIVE CHARACTERS

1. ROOT

Usually, Tap root with side branches, nodules are present.

2. STEM

Usually, Erect and woody stem, rarely herbacious, tannin and gums may also present.

3. LEAVES

Usually, Compound, bipinnate, stipule are modified into spines. In many plants leaves show sleeping movement or after having a shock.

INFLORESCENCE

Mostly, racemose.

FLORAL CHARACTERS

Usually, Complete, bisexual actinomorphic, perigynous, pentamerous.

1. CALYX

Usually, 5 sepals, gamosepalous, valvate.

2. COROLLA

Usually, 5 petals, polypetalous, valvate aestivation, small size.

3. ANDROCEIUM

Usually, numerous stamens, exerted, extrose, basifixed anther.

4. GYNOECIUM

Usually, Monocarpillary, perigynous, unilocular, placentation marginal, many ovules in locule.

POLLINATION

Usually, cross pollination by insects (entomophilly).

SEEDS

Usually, Non-endospermic or with very little endosperm.

FRUIT

Usually, It is called legume.

FLORAL FORMULA

+ ,Q , K(5) , C(5) , Aα , G1/

ECONOMICAL IMPORTANCE

1.WOOD YIELDING PLANTS

  • e.g-prosopis
  • Acacia species
  • Albizzia
  • Xyliaet

2. ORNAMENTALS

  • e.g-Mimosa pudica (chuimoi)
  • Austratian Acacia
  • Neptunia

3. FOODER

  • From leaves of prosopis,
  • Acacia
  • Dicrostachys e.t.c.

4. SOAP POPS

Acacia concinna pods have (soponim), a substance can be used as Soap.

5. CATECHU (KATHA)

Piece of hard wood

6. MEDICINAL USE

  • Katha
  • Siah Kanta
  • Entada
  • Acacia senegal

7. GUMS & DYES

  • Katha
  • Safed Babul
  • Sada Babul

IMPORTANT FAMILY MEMBERS

BOTANICAL NAME…………..COMMON NAME…………….LOCAL NAME

1-Acacia nilotica…………….Gum tree……………..Bauble, Kikar

2-Albizzia lebbek…………….Siris

3-Mimosa pudica……………..Touch-me-not…………..Chhui mui

4-Prosopis glandulosa…………Prosopis……………..Devi

5-Acacia catechu……………..Katha plant


3- ROSACEAE

CLASSIFICATION

Division

Class

Subclass

Series

Order

Family: Rosaceae / Rose family.

GENERAL CHARACTERS

It has about 100 genera and 2000 species.

HABITAT

These plants are found growing all over the world 213 species of about 29 genera are reported from Pakistan.

VEGETATIVE CHARACTERS

1. ROOT

Usually, Tap root with its usual branching.

2. STEM

Usually, Green herbaceous, cylindrical, small spines are also present.

3. LEAVES

Usually, Simple leaves with or without petiole, Opposite or alternate.

INFLORSCENCE

Usually Racemose

FLORAL CHARACTERS

Usually, Complete, bisexual, actinomorphic, perigynous, pentamerous.

1. CALYX

Usually, Sometime epicalyx may also be present, of variable number, 5 sepals are present, Gamosepalous, green, pubescent.

2. COROLLA

Usually, 5 petals or multiple of 5 petals, polypetalous, aestivation, imbricate, shape-rosaceous, full of colour.

3. ANDROCEIUM

Usually, Nomerous stamen,ditheous, anther, enerted, extrose, dorsi fixed.

4. GYNOECIUM

Usually, Monocarpillary or multiple capillary with formation of a single compound pistil. Ovary perigynous, unilocular two or more ovules are present, placentation axile when the carpels are many and syncarpous

FLORAL FORMULA

+ , Q , K(5) , C(α) , Ax , G1/ (2-5) or x

ECONOMICAL IMPORTANCE

FRUIT

Economical importance of this family is great in providing the pleasure and welfare of mankind. Plants of many famous fruits belong to this family for e.g. Apple, pear, peach, e.t.c. Perhaps they rank 3rd in commercial importance in the temperate, zone among the families of flowering plants.

ORNAMENTALS

A large no. of ornamental plants of this family are grown in parks and gardens the most widely cultivated plant for this purpose is Rosa. Many others genera are also grown for their beautiful flowers in homes and gardens.

OTHERS

Branches of crataegus and cotoneaster provide excellent walking stick and wood. The wood of pyruspastia is used for making tobacco pipes. In Asian countries rose petals are used in making Gul Khand and are also used in extraction of an essential oil, Rose oil, used as perfume or may be used as eye cleaner in certain diseases.

FAMILIAR PLANTS

BOTANICAL NAME……………….COMMON NAME…………..LOCAL NAME

Malva silvestis……………………….Apple………………..Seb

Pyrus pyrifolia……………………….Pear…………………Nashpati

Prunus amygdalus………………………Almond………………..Badam

Rosa indica…………………………..Rose………………….Gulab

Prunus persica………………………..Peach…………………Aru


4-SOLANACEAE

ALTERNATE NAME

Night shade or Potato family

HABIT AND HABITAT

It is widely distributed in temperate region and very abundant in tropical countries.

The plants are usually herbs or climbing vines but may be shrub.

VEGETATIVE CHARACTERS

1-ROOT

Tap root and branched

2-STEM

Herbacious, erect or underground(Potato)

3-LEAF

Alternate in vegetative and opposite in floral region

FLORAL CHARACTERS

INFLORESCENCE

Cyme sometimes helicoids

1-FLOWER

Pentamerous, Bisexual, Regular, Actinomorphic, Hypogynous.

2-CALYX

Five, united sepals

3-COROLLA

Five petals, united, valvate aestivation

4-ANDROCIEUM

Five stamens, Inserted on Corolla

5-GYNOECIUM

Bicarpellary, Syncarpous (Carpels fused), Placentaion axile.

6-FRUIT

Capsule Berry or Xanthium.

7-SEED

Minute with abundant endosperm.

FLORAL FORMULA

+ , O , K(5) , A5, C(5) ,

ECONOMIC IMPORTANCE

Members of this family provide drugs and food. Some plants are poisonous and other are ornamental. This family is of great economic importance as it provides food, fodder, drugs and ornamentals.

1-FOODER

  • Solanum tuberosum (Potato)
  • Lycopersicum esculentum (Tomato)
  • Solanum melongena (Brinjal)

2-CONDIMENTS

  • Fruit of capsicum
  • Capsicum frutenscens

3-EDIBLE FRUIT

  • Physalis (Cherry or Rasbhari)

4-DRUG YIELDING

  • Atropa belladonna (atropine)
  • Dotura (Daturine)
  • Used in severe cold and in eye diseases.
  • Sap of hanbane is used in dilating the pupils, white cherry is used an nerve tonic.

5-ORNAMENTAL

  • Cultivated in gardens
  • Petunaia
  • Nicotiana
  • Cestrum Schizanthus
  • Brunfelsia solanum

6-CIGARETTE MAKING

  • Nicotiania tobacum (Tobacco)

IMPORTANT FAMILY MEMBERS

BOT-NAME……………………COMMON NAME…………………….LOC-NAME

1-Solanum Tuberosum………………Potato…………………………Aaloo

2-Solanum Melongena………………Bringal………………………..Bengan

3-Lycoperscum Escalentum………….Tomato…………………………Temater

4-Capsicum Annum…………………Red-Pepper……………………..Lal-mirch

5-Petunia Alba…………………..Petunia

6-Solanum Nigrum…………………Black Night shade

7-Datura Alba……………………Thorn apple

8-Nicotiana Tobaccum……………..Tobacco………………………..Tambako

9-Atropa Belladonna………………Deadly night shade

10-Cestrum nocturnum……………..Lady of night…………………..Raat ki Rani


5-FABACEAE

ALTERNATE NAME

Papilionaceae or Pea family

HABIT AND HABITAT

Plants are herbs, shrubs or trees. Climbers, aquatic plants or xerophytes. World wide distributed.

VEGETATIVE CHARACTERS

1-ROOTS

Tap root, branched bearing tubercle containing nitrogen fixing bacteria.

2- STEM

Herbecious or woodi, erect or climber.

3-LEAF

Simple or commonly compound alternate, stipulate

FLORAL CHARACTERS

1- INFLORESCENCE

Racemose, rarely solitary.

2- FLOWER

Bisexual, irregular, zygomorphic, hypogynous.

3- CALYX

Five sepals, united

4- COROLLA

Five petals, usually free.

Corolla is papilionaceous (Butterfly shaped). In this form the petals are 5, one of them is usually large and clawed. This petal is called standard or “Vexillum” The two lateral ones, which are free are called as “Wings” and two anterior inner most fuse to form a boat shaped structure called the “Keel” or “Carina”.

5- ANDROCIEUM

Stamens (9) +1 i.e 9 fuse to form a round sheath around the pistil while tenth is free.

6-GYNOECIUM

Monocarpellary, ovary unilocular, ovule numerous on marginal placenta.

7-FRUIT

Legume or pod.

8-SEED

EX-albuminous.

FLORAL FORMULA

+ , Q , K(5) , C 1+2+(2) , A(9)+1 , G1

ECONOMIC IMPORTANCE

The family is of considerable importance, as a source of high protein food, oil and forage as well as for ornamental purposes. Chief importance lies in the pulses, belonging to this family. All types of pulses (Dalls) are actually the seeds of this family which are rich in protein.

1- FOOD & FORAGE

  • Cicer arietinum (Gram)
  • Pisum sativum (Pea)
  • Lens esculanta (Masure)
  • Phaseolus aureus (Mung)
  • Phaseolus mung (Urad/Mash)
  • Phaseolus vulgaris (kidney bean/Lobia)
  • Medicago sativa alfalfa (Lusan)
  • Vicia
  • Melilotus & Trifolium

2- FURNITURE & BUILDING PURPOSE

  • Butea
  • Dilburgia

3- OIL EXTRACTION

  • Arachis hypogea (Peanut/Moongphali)

4- DYES

  • Indigofera tinctoria (Neel)
  • Butea monosperma (Yellow dye)

5-MEDICINAL PURPOSE

  • Glycyrrhiza glabra (Cough & cold treatment)
  • Clitoria termatea (Snake bite treatment)

6- ORNAMENTAL PLANTS

  • Lathyrus
  • Lupinus
  • Clitoria
  • Butea
  • Abrus precatorious, used by jewellars as weights called “Ratti”.

IMPORTANT FAMILY MEMBERS

BOT-NAME……………….COMMON NAME………………..LOCAL-NAME

1- Lathyrus Odoratus………..Sweet pea………………….Matter

2- Arachis Hypogea………….Peanut…………………….Moongphali

3- Cicer Arietinum………….Gram………………………Channa

4- Dalbergia Sisso………….Red-wood…………………..Shesham

5- Pisum Sativum……………Edible pea

6- Sesbania aegyptica……….Sesbania


6-POACEAE

ALTERNATE NAME

GRAMINAE/ GRASS FAMILY

HABIT AND HABITAT

  • The species are most numerous in the tropics but they are also abundant in temperate region.
  • This family is monocot (one cotyledon in seed)
  • Mostly annual or perennial herbs or shrubs.

VEGETATIVE CHARACTERS

1- ROOTS

Adventitious, fibrous or fascicled.

2- STEM

Cylindrical, Conspicuous nodes and hollow, although solid stems are also found as sugar cane.

3- LEAF

Legulate, alternate leaf sheath mostly open sessile, lamina narrow and ribbon shaped.

FLORAL CHARACTERS

1- INFLORESCENCE

Compound spikes.

2- FLOWER

Sessile, bracteate, incomplete, bisexual or unisexual and zygomorphic.

3- PERIANTH

It is combined structure instead of calyx and corolla. Number 2 or 3 membranous scales called “ Lodicules”

4- ANDROECIUM

Usually 3 stamens, filaments long, free anther versatile.

5- GYNOECIUM

Tricarpellary, syncarpous though only one is functional, unilocular, single ovule, style short 2-3, stigma feather like.

6- FRUIT

Grain or coryposis.

7- SEED

Endospermic, monocotyledonous.

FLORAL FORMULA

+ or O , O or O or O , P2 (lodicules) , A3 or 0 , G1 or 0

ECONOMIC IMPORTANCE

The family poaceae has great importance than any other family of flowering plants.

1- FODDER AND FOOD STUFF

  • Triticum indicum
  • Avena sativa
  • Zea mays
  • Oryza sativa
  • Hordeum vulgare
  • Pennisetum typhoideum

2- SUGAR MAKING

  • Saccharum officinarum (sugar cane)

3-PAPER MANUFACTURING

  • Certain species of Grasses

4- VEGETABLES & SOUP DISH

  • Sugar cane
  • Bamboo-shoots

IMPORTANT FAMILY MEMBERS

BOT-NAME…………………………COM-NAME…………………….LOC-NAME

Triticum Indicum……………………..Wheat……………………….Gandum

Avena Sativa…………………………Oats

Zea Mays…………………………….Indian corn………………….Makai

Oryza Sativa…………………………Rice………………………..Chawal

Saccharum Officinarum…………………Sugar cane…………………..Ganna

Hordeum Vulgare………………………Barly……………………….Joo

Pennisetum Typhoideum…………………Bajra

Bambusa Arundinacea…………………..Bamboo………………………Banns

Cymbopogon Jawarancuza……………………………………………..Lemon Grass

Cynodon dactylon…………………………………………………..Lawn Grass


DOUBLE FERTILIZATION

After pollination, the tube nucleus of the pollen grain forms pollen tube, while generative nucleus divides into two male (sperm) gametes.

When pollen tube reaches the embryo sac through micropyle, one of the male gametes fuses w/t egg cell and forms “oospore (zygote)”,it develops into seed. Another male gamete fuses with definitive nucleus and forms “Endospermic nucleus”, w/c develop into endosperm of seed or food storage tissue of seed.

Because two times fertilization occurs so it is called “Double fertilization”.

THE FLOWERS

The flower is a modified shoot and meant for sexual reproduction. It is collection of four different kinds of floral members, arranged in four separate whorls. The upper two whorls are essential or reproductive whorls whereas lower two are helping or accessory whorls. The flower is born on an axis which consists of two parts the pedicel or stalk of flower and the thalamus is swollen end of the axis on which the floral leaves are inserted. The floral whorls are arranged on the thalamus in a particular order one just above the other. These four whorls are as follows.

CALYX

It is the first or lower most whorl of the flower, the calyx is generally green is colour. Each member of calyx is known as sepal. Sometimes sepals become coloured called petaloid. Such as in gold mohur. The calyx is non essential or accessory part of flower.

FUNCTIONS

  1. Protection of floral bud
  2. Assimilation when green in colour
  3. Attraction when coloured and showy
  4. Modified into papus which helps in dispersal

COROLLA

It is the second non essential floral whorl of flower. It is brightly colored. Each member of its known as petal. However there is no differentiation of calyx and corolla in some flowers. It is called perianth.

FUNCTIONS

  1. The corolla attracts insects and hence help in pollination.
  2. It encloses stamens and carpels.
  3. It protect the stamens and carpels from external heat rain and insects attack.

ANDROCIEUM

It is the third essential floral whorl and each member of it is known as stamen. The stamen is a male reproductive body and consists of filament, anther and connective. The anther bears four chambers of pollen sacs, each chamber is filled with granular mass of small cells called pollen grains. Each pollen grain consists of two walls, the outer exine and inner intine.

FUNCTIONS

It is the male reproductive body and hence possess male gametes which take part in reproduction.

GYNOECIUM

It is the fourth essential floral whorl and its component parts are called carpals. The carpel is a female reproductive body, it may be one or more than one, and may be united or free. Each carpel consists of stigma, style and ovary. The stigma is terminal end which receives the pollen grain. It may be smooth or hairy and becomes sticky on maturity, The style is slender projection of ovary, It helps in pollination and later on dries up. The ovary is swollen basal portion, which encloses minute egg like bodies called ovules. The ovule possess egg cells.

FUNCTIONS

The gynoecium is a female reproductive body. It possess the egg cells which take parts in reproduction.

AESTIVATION

It is the arrangement of floral whorls i.e. the sepals or petals in a floral bud, it is of following types:

(A) VALVATE

The members of a whorl lie close to each other and do not overlap e .g Calatropis.

(B) TWISTED

One margin of a floral whorl overlaps that of the next one. It may be clockwise or anti clockwise e.g. China rose.

(C)VEXILLARY

When petals are five, two internal are overlaped on both margins by two petals, these two are overlaped by a single largest posterior petal e.g. Pea bean etc.

(D)IMBRICATE

When one of the sepal or petal is internal and other external and each or remaining one is overlaped on one margin and it overlaps the next one on other margin e.g Gold mohur .

  1. Velvate.
  2. Twisted
  3. Vexillary
  4. Imtricate.

INSERTION OF FLORAL LEAVES ON THE THALAMUS

The floral leaves are inserted on the thalamus in a particular order, it is of following types:

(A) HYPOGYNOUS

In some flowers the thalamus is convex or conical and ovary occupies the highest position on it. However other floral whorls are inserted below the ovary, such flower is known as hypogynous and ovary as superior. E.g. Mustard.

(B ) PERIGYNOUS

In certain flowers thalamus forms a flattened circular disc due to the fact that sises of thalamus grows up to the same level. The apex of thalamus is in the middle of the disc at which gynoecium develops, whereas at the rim or margin sepals, petals and androecium are inserted. They are round about it and hence are called perigynous, such as in pea. Sometimes the apex of thalamus grows up in conical shape as in raspberry. Whereas in some cases the calyx forms a cup shaped structure called calyx tube such as in wild rose.

(C) EPIGYNOUS

In some flowers the concave receptacle surrounds the ovary and is fused with it. The sepals, petals and stamens apparently arise from the tip of the ovary such ovary is said to be inferior. E.g. Sunflower, apple, guava, pear etc.

IMPORTANT TERMS TO DESCRIBE A FLOWER

COMPLETE: When all the four floral whorls are present.

INCOMPLETE: When any of the whorl is absents.

BISEXUAL: The stamen and carpel both are present.

UNISEXUAL: The flower possess either stamen or carpel.

STAMINATE: Only stamens are present (male).

PISTILATE: When flower possess only carpels (female).

NEUTER: The stamens and carpels both are absent.

SYMMETRY

+ACTINOMORPHIC

When a flower can be divided into two equal halves by any vertical section passing through centre.

+ ZYGOMORPHIC

When it can be divided into two similar halves by only one vertical section.

+ IRREGULAR

The flower can not be divided into two similar halves by any vertical plane.

COHESION OF STAMEN

+ MONOADELPHOUS

When filaments are united in a bundle and anthers are free e.g. China rose.

+ DIADELPHOUS

The filaments are united into two bundles and anthers are free e.g. Pea.

+ POLYADELPHOUS

The filaments are united into more than two bundles and anthers are free.

+ SYNGENECIOUS

The anthers are united together and filaments are free e.g. Sunflower.

ADHESION OF STAMENS

+ EPIPETALOUS

The stamens adhere to corolla, wholly or partially by their filaments.

+ GYNANDROUS

When stamens adhere to carpels e.g. Calatropis.

LENGTH OF STAMENS

+DIDYNAMOUS

The stamens are four, two of them short and two long e.g. Nerium.

+TETRADYNAMOUS

The stamens are six but two short and four long e.g. mustard.

GYNOECIUM

+ MONOCARPELLARY

The pistil consists of only one carpel, it is also known as simple pistil e.g. Pea, Bean

+ POLYCARPELLARY

The pistil consists of two or more carpels, it is also known as compound pistil e.g. Rose.

+ SYNCARPOUS

The carpels are united into one ovary e.g. Mustard.

STIGMA

+ CAPITATE

When stigma is rounded and knob like. Bi, tri or Multified: when stigma is branched into two , three or many.

+ FEATHERY

When stigma is feather like.

+ FLATTENED

When sitgma is flat.

+ POINTED

When stigma is pointed.

+ LINEAR

When it is long and narrow.

STYLE

+ TERMINAL

When style arise from top of ovary; such as in Mustard.

+ GYNOBASIC

When it arise between the lobes of the ovary from its base;such as in Salvia.

+ PEDICILLATE

When flower is born on a stalk or pedicel. (STALKED)

+ SESSILE

When stalk is absent

+ BRACTEATE

When flower is developed in the axil of a bract

+ EBRACTEATE

When bract is absent.

+ DIMEROUS

When each floral whorl has two floral leaves (Dicot)

+ TRIMEROUS

When floral whorl has three floral leaves (Monocot)

+ TETRAMEROUS

When each floral whorl has four floral leaves; and so the pentamerous Dicots)

CALYX

+ PETALOID

The calyx having other then green colour.

+ CAMPANULATE

Sepals fused to form bell shaped structure.

+ POLYSEPALOUS

When sepals are free from one another.

+ GAMOSEPALOUS

When sepals are fused or united with one another.

PETALS

+SEPALOID

The petals are green in colour.

+CRUCIFORM

Petals are arranged in form of a cross.

+POLYPETALOUS

When petals are free from one another.

+GAMOPETALOUS

When petals are united with one another.

+PERIANTH

When calyx and corolla can not be distinguished with one other due to similar shape and colour.

PERIANTH

+SEPALOID

When perianth leaves are green.

+POLYPHYLLOUS

When perianth leaves are free from one another.

+GAMOPHYLLOUS

When perianth leaves are fused.

FLORAL FORMULA

The floral formula is represented by various symlols. The symbols used in floral formula are as follows.

SYMMETRY OF THE FLOWER

  • Zygomorphic = +
  • Actinomorphic = O
  • SEXUALITY
  • Bisexual = Q+
  • Unisexual (male)
  • Unisexual (female)
  • Neuter =
  • PERIANTH
  • Perianth = P
  • Polyphyllous = Pn n=number of perianth leaves.
  • Gamophyllous = (n) “ “ “
  • CALYX
  • Epicalyx = Epi K
  • Petals = C
  • Calyx = K
  • Polypetalous = Cn,
  • Polysepalous = Kn, n= number
  • Gamopetalous = C(n)
  • Gamosepalous = K (n) of sepals
  • ANDROECIUM
  • Androecium = A
  • Androecium free = An n= number of stamens
  • Androecium United = A (n)
  • Epipetalous = C-A
  • GYNOECIUM
  • Gynoecium = G
  • Apocarpous = Gn
  • Syncarpous = G (n)
  • Ovary inferior = G
  • n= number of carpels
  • Ovary Superior = G

FLORAL DIAGRAM

The features of flower in flora formula are represented by symbols, while in floral diagram by the diagram of its various floral leaves alongwith actual number and position.

MOTHER AXIS: It is represented by a Dot above the floral diagram. It actually shows the position how a flower is born. The position of it can be seen from upperside. It may be between two adjacent sepals or a single sepal.

PLACENTATION

It is the arrangement of placenta which are cushion like ridges in the ovary, The placenta bear ovules. In simple ovary placentaion is marginal, whereas in compound ovary it may be parietal, axile, free central, basal and superficial.

(A) MARGINAL

In a simple ovary or monocarpellary pistil, the ovules are arranged along the fused margins, these margins forms a cushion like tissue called placenta along the ventral suture on the inner surface of ovary wall e.g. Pea, Gram, Bean, etc.

(B) PARIETAL

In a compound syncarpous and unilocular ovary, the fused margins of the carpals swells up to form placentas, to which ovules are attached. The placentas lie along the wall of ovary and their number indicates the number of carpels forming ovary e.g. cucumber, Melon; etc.

(C) AXILE

In a polycarpellary syncarpous pistil and multilocular ovary, each carpel is folded along its mid-rib and meets in the centre of the ovary. The ovules are attached to this central axis e.g. Tomato, China rose, etc.

(D) FREE CENTRAL

In a compound and unilocular ovary the ovules are situated all around the central axis, which arise from the thalamus and not fused with the margins of the carpels. However in some plants the axile placentation becomes free central due to breaking down of septa e.g. Pink (Diantus)

(E) BASAL

In a unilocular ovary the placentas develops directly on the thalamus and bears single ovule at the base of ovary e.g. Sunflower, Cosmos etc.

(F) SUPERFICIAL

In a multilocular ovary, the ovules are not on the margins of the carpels; but over the whole inner surface of the partition walls e.g. Waterlily.

TYPES OF PLACENTATION

1.FOR SIMPLE OVARY

Only one type, MARGINAL.

2.FOR COMPOUND OVARY

  • Exile
  • Central
  • Parietal
  • Basal
  • Superficial.

1. MARGINAL PLACENTATION

In marginal placentation, the ovary is one chambered and the placenta develops along the junction of the two margins of the carpel, called the ventral suture.

EXAMPLES

Pea, wild pea, gram, gold mohr, and cassia are common examples.

2. AXILE PLACENTATION

In the axile placentation the ovary is two to many chambered and the placenta bearing the ovules develop from the central axis e.g. Potato, Tomato, Petunia, China rose etc.

3. CENTRAL PLACENTATION

In this case the septa in the young ovary soon break down so that the ovary becomes one-chambered and the placenta develops all round the central axis e.g. Dianthus, Saponaria etc.

4. PARIETAL PLACENTATION

The ovary is one chambered and placenta develops on the inner wall of the ovary e.g. papaw, orchids etc.

5. BASAL PLACENTATION

The ovary is unilocular and placenta develops directly on the thalamus e.g. sunflower, cosmos etc.

6. SUPERFICIAL PLACENTATION

The ovary is multilocular, carpels are numerous and placenta develops all round the inner surface of the partition walls as in waterlily.

INFLORESCENCE

The branch system of the floral region bearing a group of flowers is called INFLORESCENCE. The term inflorescence refers to the arrangement of flowers on plant.

TYPES OF INFLORESCENCE

The flowers may be solitary or grouped into clusters, Such clusters vary in shape and arrangement. On the basis of arrangement of flowers, inflorescence is classified into

1-RECEMOSE

  1. In this case, the main axis of inflorescence does not end in a flower.
  2. Main axis continues to grow and gives off flowers laterally.
  3. The lower or outer flowers are always older and open earlier than the upper or inner ones.
  4. Order of opening of flowers is called centripetal.

EXAMPLES

Mustard, Gold mohr, Mulberry, birch etc.

KINDS OF RECEMOSE INFLORESCENCE

Recemose inflorescence has following main types on the basis of nature and shape of the peduncle:

I- PEDUNCLE ELONGATED

It is further subdivided into following types;

1. RECEME

The main axis in this case is elongated and it bears laterally a number of flowers which are all stalk e.g. radish, mustard, dwarf gold mohur etc.

2. SPIKE

In this case the flowers are sessile e.g. Adhatoda, Achyrnthes etc.

3. CATKIN

This is a spike with a long and pendulous axis which bears unisexual flowers e.g. Musberry, Acalypha, Birch and Oak etc.

4. SPADIX

This is also a spike with a fleshy axis which is enclosed by one or more large bracts called spathes e.g. Banana, Palms etc.

II- PEDUNCLE SHORTENED

It is further divided into following types;

1. CORYMB

Here the main axis is comparatively short, and the lower flowers have much longer stalk than the upper ones. Hence all the flowers are brought more or less to the same level e.g. candytuft, wall flowers etc.

2. UMBEL

Here the primary axis is short and it bears at its tips a group of flowers which have pedicles of more or less equal length so that the flowers are seen to spread out from a common point. In the umbel there is always a whorl of bracts forming an involucre, and each flower develops from the axil of a bract, e.g. Carrycumin, Coriander etc.

III- PEDUNCLE FLATTENED

The best example is seen in sunflower family, here the inflorescence is called the head as the capitulum.

HEAD OR CAPITULUM

  1. A dense cluster of sessile or sub-sessile flowers, on a compound receptacle is called capitulum.
  2. Main axis is almost flat, bearing sessile flowers.
  3. Outer flowers are older and open earlier.
  4. The florets are commonly of two types

I- RAY FLORETS

II- DESC FLORETS

EXAMPLES

Capitulum is characteristic feature of sunflower family e.g. sunflower, marigold; zinnia, cosmos etc.

IV- SPIKELET INFLORESCENCE

It is a kind of racemose inflorescence. There are three bracts at its base called glumes. The lower two without flowers are called empty glumes. The third glume has flower in its axil and called Lemma. Just opposite to lemma, there is small bractcole called Palea. Flowers are covered by their respective lemma and palea. This type of inflorescence is characteristic feature of family Poaceae (Grass Family).

2-CYMOSE

  1. Here the main axis ends in a flower and similarly the lateral axis also ends in a flower.
  2. The growth of each axis is checked due to presence of flower on its tip.
  3. The terminal flowers are always older and open earlier than the lateral ones.
  4. The order of opening of flowers is centrifugal.

EXAMPLES

Jasmine, Teak, Night Jasmine, Ixora.

KIND OF CYMOSE INFLORESCENCE

I- UNIPAROUS (MONOCHASIAL) CYME

Main axis soon ends into a flower and produces only one lateral branch at a time ending in a flower. The succeeding lateral branches again follow the same mode of producing flowers. If the succeeding branches are produced on alternate side, it is called Scorpiold cyme (cotton, forget-me-not). Whereas, if the succeeding branches are produced on same side, it is called Helicoid (sundew).

II- BIPAROUS (DICHASIAL) CYME

Main axis soon terminate into a flower and produces two flowers. This mode is followed by each succeeding flowers (Pink, Night- Jasmine).

POLLINATION

It is the process of transference of pollen grains to the stigma of the flower.

TYPES OF POLLINATION

Pollination is of two types.

  • Self pollination or Autogamy.
  • Cross Pollination or Allogamy.

(A)SELF POLLINATION

It is the transfer of pollen grains from the anther of a flower to the stigma of the same flower.

METHODS OF SELF POLLINATION

In self pollination, only one flower is concerned to produce the offspring. Irrespective whether the flower is unisexual or bisexual self pollination can take place by two methods

I-HOMOGAMY

In homogamy the anther and the stigma of a unisexual flower mature at the same time. In rare cases it may takes place by insects or wind.

II- CLEISTOGAMY

In cleistogamy the flower never open. They remain closed and the pollination takes place in the closed flower such as in pansy (viola), balsam (impatiens), oxalis, etc.

B)CROSS POLLINATION

It is transfer of pollen grain from the flower of one plant to the stigma of flower of another plant of the same species.

METHODS OF CROSS POLLINATION

It takes place by external agencies. These agents are insects, animals, birds, wind and water.

I- ENTOMYPHILY

The pollination takes place by insects. It is of general occurrence in plants.

II ANEMOPHILY

The pollination is brought about by wind.

III HYDROPHILY

The pollination takes place in aquatic plants particularly the submerged ones, through the medium of water e.g. Hydrilla and vallisneria

IV ZOOPHILY

The pollination is carried out by birds, squirrels, snails etc. Examples are Bombax and Erythrina.

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