The basics of Floral plant classification

Mona soliman alwahibi

Practical BOT222  decision

The basics of Floral plant classification

Plant taxonomy

Is the science that finds, describes, classifies, identifies, and names plants

The basis of classification of plants

This is the most abundant and widespread group of plants on Earth. Flowering plants are found in most habitats, from deserts to polar regions, and include species of trees, shrubs, and herbs. The flowers are the reproductive structures that produce new plants

Flower

Flower Parts

Receptacle = Place on Stem where Floral Parts originate & attach

Sepals = Lowest order of floral organs, first to develop, can be green & leaf-like, Collectively = Calyx

Petals = Inserted on the Receptacle just above the Sepals, usually brightly colored, Collectively = Corolla

Perianth = Collective term for Sepals + Petals

 

Stamens = Inserted above Petals, consists of Anther & Filament, Collectively = Androecium

Anther - Part of Stamen that Produces Pollen

Filament - Stalk that bears the Anther

 

 

 

 

 

 

Carpel = Inserted above Stamens, uppermost floral organ, Consists of Stigma, Style & Ovary, Collectively = Gynoecium

Stigma - Tip of the Carpel, Receptive to Pollen

Ovary - Base of the Carpel, contains Ovules

Style - Connects the Stigma to the Ovary

 

 

 

 

 

 

Stigma – the pollen receptive portion of the gynoecium
Style – the elongated portion between stigma and ovary specialized for pollen tube growth
Ovary – the basal portion that surrounds and protects the ovules (meiosis occurs within the ovule).

 

 

 

 

 

 

 

§  Apocarpous Gynoecium has Free Carpels

§  Asyncarpous  Gynoecium has Fused Carpels

 

§  A Synandrous Androecium has Fused Stamens (Either the Filaments or the Anthers may be Fused) §  A Sympetalous Corolla has Fused Petals. §  A Synsepalous Calyx has Fused Sepals.

 

 

 

 

 

 

 

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches.

Divided into two main groups

& Racemose  Cymose

Types of racemose inflorescence

Types of cymose inflorescence                     

Aestivation

the arrangement of sepals and petals or their lobes in an unexpanded flower bud .

The following types are commonly met with:

1.     Valvate 

2.     Imbricate

3.     Convolute

4.     Quincuncial

 

Symmetry

1- Actinomorphic (radial, regular) – divisible into equal halves by two or more planes

2- Zygomorphic (bilateral, irregular) – divisible into equal halves in one plane only A few flowers have no plane of symmetry and are called asymmetrical

Placentation

 

floral diagram

Floral formula

Is a code written for the expression of the floral parts in the form of the equation to make clear the classification and description of the flower

+	Actinomorphic	Ca	Calyx
%	Zygomorphic	Co	Corolla
	Androgynous	Pe	Perianth
♂	male -rep	A	Androecium
♀	female  -rep	G	Gynoecium

                  



BOT 222 


                                       ..