morphology of flowers class 11th
THEORY
1. Flower: The flower is "a reproductive shoot bearing nodes and modified leaves" . The internodes are highly condensed.
2. Parts of Flower: Flower is a modified shoot
responsible for reproductlon. It consists of four types of parts called four whorls. These are calyx, corolla,
androecium and gynoecium. Some flowers contain bracts and epicalyx also.
{OF all androeciumand gynoecium whorls are actively involved in reproduction, hence are called essential whorls and others the non-essential whorls.}
<~>Some important terms associated with a flower:
Bract ____A leaf-like structure at the base of flower.
Bracteole ____A leaf-like structure present on any part of flower stalk (pedicel).
Bracteate ___Flower with bract.
Ebracteate ____(E-without; bracteate-bract) Flower without bract
Bracteolate ____Flower with bracteoles
Ebracteolate____Flower without Bracteoles
Pedicellate ____Flower with stalk (pedicel).
Sessile ____Flower without stalk (pedicel).
Complete____Flower with all the four whorls.
Incomplete____Some whorls missing.
Actinomorphic____Bower can be divided
into two equal halves
through any vertical plane.
(2). MORPHOLOGY OF FLOWERS.
Zygomorphic___Flower can be divided into two
equal halves only along one vertical
plane.
Bisexual___Rower with both stamenand carpels
present in it (Hermaphrodite).
Unisexual___Flower with only one sex either stamen or
carpel is present.
Pistillate___Flower with only female organ, i.e., carpel.
Staminate___Flower with only male organs in it, i.e.,
stamen
Trimerous___leaves of each whorl are three or its
multiples.
Tetramerous___Floral leaves of each whorl are four or its multiples.
Hypogynous___All the whorls arise below the ovary,
making ovary superior, e.g, China rose.
Epigynous___All the whorls arise above the ovary making
ovary inferior, eg, Apple, Cucumber.
Perigynous___All the whorls arise from middle of the
ovary, e.g Rose.
Morphology of Flowers class 11th NCERT
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