Morphology of flowering plants deals with the study of external forms and features of different plant organs. These can be root, stems, leaves, flower, seed, fruits, etc. Morphological characteristics play a significant role in the identification of plants. These characteristics also aid in classifying plants in their respective groups and establishing phylogenetic relationships etc. Many different types of flowering plants are found on the earth. They vary in their forms, lifespan, habitat, and mode of nutrition.
The stamens in the flower of Salvia, mustard, radish, and turnip are of different length [NEET-II 2016].
The Brassica flower can be cut into two equal halves from any plant. So, it shows the radial symmetry. These flowers are referred to as actinomorphic flowers. The flowers of Trifolium, Pisum, and Cassia can be cut into two equal halves only at one plane so they are called zygomorphic flowers. These three flowers belong to the family – Fabaceae [NEET-II 2016].
Coconut milk represents free-nuclear endosperm where the division of primary endosperm nucleus is not followed by formation of the cell wall (cytokinesis) thus all nucleus remain free in liquid form, It is rich in plant hormone cytokinin [NEET-I 2016].
Vexillum is a term used for standard petal of a papilionaceous corolla [NEET-I 2016].
Onion has a bulb which is a short, underground modified stem surrounded by fleshy modified leaves that store food for shoot formation. It has corymb inflorescence [EAMCET 2015].
Datura belongs to Solanaceae family with epipetalous stamens. Allium is of Amaryllidaceae family with epipetalous stamens. Petunia belongs to Solanaceae family with epipetalous stamens. Crotolaria belongs to Fabaceae family with monadelphous stamens [EAMCET 2015].
Keel represents petal in vexillary aestivation, which is a characteristic of the family – Fabaceae, i.e. Indigofera. Papilionaceae is subfamily – Fabaceae, which has bilateral symmetry. It follows vexillary aestivation. A single upper posterior part is known as the banner. Two lateral compressed petals called wings and a pair of anterior small fused petal forms keel. Keel has concave sides which make them fused at bases [CBSE AIPMT Re – 2015].
Cucumber is a member of the Cucurbitaceae family. In the members of this family, the flowers are unisexual. with male and female flowers on different plants (dioecious) or on the same plant (monoecious) [CBSE AIPMT Re-2015].
Leaves are modified into the spine in Opuntia (Xerophyte) so as to reduce the surface area and minimize the rate of water loss by evaporation and transpiration. Besides, they also provide protection to the plant from grazing animals [Uttrakhand 2015].
Leaf tendrils are specialized stem, leaf or petiole with a threadlike shape that is used by climbing plants for support attachment and cellular invasion by parasitic plants, generally by twining around suitable hosts [amu 2015].
The plants have hypogynous flower mustard, brinjal, China rose, Lupin, gram, chili, Petunia, tomato, potato, onion Aloe, and tulip. There is a lot variation in the morphology of flowering plants. [NEET 2013].
Ginger (Zingiber officinale) is a straggling sympodial rhizome, which is a perennial, fleshy, dorsiventral, horizontal, usually branched, underground stem growing beneath the surface of the soil. It possesses nodes and internodes, scaly leaves, axillary buds and roots at their node [UPCPMT 2013].
Mature endosperm with any degree of irregularity and unevenness on its surface is called ruminant endosperm. It is known to occur in about 32 families of angiosperms. In the family – Annonaceae, the ruminate endosperm is found [OJEE 2013].
Stolons are special kind of runner, which initially grow upwards like ordinary branches and then arch down to develop new daughter plants on coming in contact with the soil. Sucker is a subaerial branch, that arises from the main stem. Initially, it grows horizontally below the soil surface and later grown obliquely upwards [Manipal 2013].
Picher plant – Morphology of flowering plants
Nepenthes (Pitcher plant) is an insectivorous plant of the tropical region. The pitcher is a modified lamina leaf are alternate and modified with a foliaceous leaf base. The upper part of the petiole is elongated and tendrillar, whereas leaf blade (Lamina) is modified into the pitcher, which collects a small amount of water containing the digestive enzyme. Insects that slip into water are not allowed to come out by the hair near the rim [OJEE 2013].
The apocarpous condition arises when the number of carpels is two or more and they are free from each other, e.g. Clematis, Michelia (Magnoliaceae), Aconitum, Ranunculus (buttercup), etc [CBSE AIPMT 2012].
Onion is a simple tunicated layered bulb, while ginger is a straggling rhizome having uniparous chyme branching with the sympodial axis [CBSE AIPMT 2012].
In Cocos nucifera (coconut), the epicarp is membranous, mesocarp is fibrous (hence, called fibrous drupe and yields coir) and endocarp is stony [Manipal 2012].
When some other floral parts participate in the formation of fruits they are called False fruits, e.g. thalamus in apple form the fruit. Thus, it is a false fruit [Manipal 2012].
Aril is the edible part in the fruit of litchi. The aril is an accessory seed covering formed from an outgrowth at the base of the ovule. The fleshy thalamus is the edible part of apple (Pyrus malus). Juicy testa is the edible part of the pomegranate (Punica granatum) [Manipal 2012].