Morphology of Plants

Flowering plants are the most dominant plants of the earth, exhibit some variations in
morphology, possess well-developed shoot and root systems, which is positively geotropic and
hydrotropic and negatively phototropic, and develops from radical. Dicot plants have tap root system
and monocots have fibrous root system. Roots help in fixation of plant in soil, and absorption of water
and minerals. They also help in storage of food, mechanical support, climbing, photosynthesis, respiration,
absorption of moisture, parasitism, symbiosis and reproduction. On the other hand, shoot system is
developed from plumule, negatively geotropic and hydrotropic, and positively phototropic, which is
differentiated into stem, leaves, flowers and fruits. Stem possesser node, internode, leaves, hairs, axillary
& apical buds.Stem helps in storage of food, reproduction, protection, climbing and photosynthesis.
On the basis of types of venations, there are two types of leaves – reticulate and parallel. Leaves are
also of two types – simple and compound. On the basis of arrangement, of leaves are of three types –
alternate, opposite and whorled. Leaves help in storage of food, support, climbing and protection.
Arrangement of flowers is known as Inflorescence, which is of two types – racemose and
cymose. A typical flower consists of four whorls – calyx, corolla, androecium and gynoecium. Arrangement
of sepals or petals in flower is called aestivation, which are five types – valvate, twisted, imbricate,
quincuncial and vexillary. Of these, androecium is composed of stamens, which may be free or united;
Each stamen consits of filament, anther and connective, while gynoecium is made up of carpels, consists
of stigma, style and ovary. Arrangement of ovules within ovary is known as placentation, which may be
marginal, axile, parietal, basal and central. After fertilization, ovary is converted into fruit and ovules into
seeds. There are three types of fruits – simple, aggregate and composite. Fleshy fruits are of three types
– drupe, berry and pome. Seeds are either monocotyledonous or dicotyledonous, exospermic or
endospermic. Floral features of any plant is exhibited by floral diagram and floral formula.

Read More  DIGESTIVE SYSTEM -BIOLOGY- TNPSC,TET,RRB,SSC SCIENCE (GK) STUDY MATERIAL

Be the first to comment

Leave a Reply

Your email address will not be published.


*