Set-II: Past Entrance Papers

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(b) In the basal type of placentation the ovary is unilocular and ovules and generally reduced to one borne at the base of the ovary, e.g., Compositae.

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(d) In the bean family the two-in-one petal is called the keel, like the keel of a boat. Bean blossoms with this configuration are said to be papilionaceous.

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(b) A flower in which floral parts arise from around the ovary is called perigynous. In this, the ovary is half inferior and half superior. It can be seen in the flowers of plum, peach, etc.

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(a) China rose of Family Malvaceae possess numerous stamens. The filaments of stamens are united in one group thus forming a staminal tube around the style. Such stamens are called monadelphous.

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(a) Scutellum is the tissue in a grass or wheat or maize seed that lies between the embryo and the endosperm. It is the modified cotyledon, being specialized for the digestion and absorption of the endosperm.

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(a) Opuntia is a xerophytic plant that lives in a dry habitat. The plant has fleshy organs where water and mucilage are stored. The stem is modified into a flat green structure, therefore, Opuntia is also called as phylloclades.

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(d) In cotton, china rose and lady’s finger margins of sepals or petals overlap that of the next one this mode of arrangement (aestivation) is called twisted.

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(c) The plants belonging to the Family Fabaceae such as soybean, pea, sem, moong, gram, etc have the floral formula

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(b) Flowers in pea have diadelphous stamens. The floral formula for Solanaceae is

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(c) This is the floral formula of tobacco. It belongs to the family Solanaceae. The flower is actinomorphic, bisexual, 5 sepals gamosepalous, 5 gamopetalous corolla, 5 epipetalous stamens, and 2 carpels syncarpous having superior ovary.

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(b) In flowering plants, placentation occurs where the ovules are attached inside the ovary. An example of axile placentation is citrus(lemon). In this type of placentation, the ovary is sectioned by radial spokes with placentas in separate locules.

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(d) The vegetative propagation in mint (Mentha arvensis) occurs by sucker. Sucker is a non-green underground specialised stem developing from the underground base of an erect shoot or crown.

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(d) Replum is a false septum formed due to the ingrowth of the parietal placenta. This makes the ovary bilocular. It is mainly seen in the ovary of flowers of the Brassicaceae (Cruciferae) Family e.g., mustard, candytuft, etc.

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(a) During the process of the development of the embryo, the food stored up in the endosperm is continuously drawn up by the developing embryo and thus completely exhausted. Such seeds are known as exalbuminous or non-endospermic. The common examples are exalbuminous – gram, pea, bean, tamarind, orchid, etc.

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(d) A pentamerous actinomorphic flower is one where the floral parts are in multiples of five and the flower can be divided into two equal halves in more than one plane. Gynoecium is bicarpellary, and syncarpous, forming a superior bilocular ovary. Each locule has many ovule on axile placentation. Members of solanaceae are characterised by the presence of an obliquely placed septum in the ovary and highly swollen placentae.

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(a) Long filamentous threads of maize are the styles of the ovaries. In fact, these are the longest styles in plants.

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(a) Single cotyledon of the embryo in cereal grain is represented by scutellum. Coleoptile represents the covering of the stem. Coleorrhiza represents the covering of the root.

Prophyll is a plant structure resembling a leaf (as a bracteole) or consisting of a modified or rudimentary leaf (as a foliar primordium).

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(c) In sweet pea(Pisum sativum), the placentation is marginal, in which, the placenta develops along the junction of two carpels, in a unilocular ovary.

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(d) Vivipary is the condition when seeds germinate on the plant. It is an undesirable character for annual crop plants because germinated seeds cannot be stored under normal conditions for the next season.

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(d) Mango (Mangifera indica) of Family Anacardiaceae is a drupe. The edible part of the mango is mesocarp.

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(b) Mesocarp is the edible part of Mangifera indica (Mango).

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(c) The juicy hair-like structures in the lemon fruit develop from the inner side of the endocarp (from the placenta).

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(b) The aleurone layer in maize grain is specially rich in proteins.

Aleurone is a protein found in the endosperm of many seeds. It forms the outermost layer of the seed coat in some grains. During seed germination, hydrolysis in the seed causes the aleurone cells to break down into amino acids. Once triggered by hormones released from the embryo, the aleurone synthesises enzymes in order to break down the starchy endosperm supplying sugars to drive the growth of roots and germination. Aleurones can have two different morphological features, homogenous and heterogenous. The homogenous aleurone is consists of similar protein bodies (e.g. Phaseolus vulgaris) while the heterogenous aleurone consists of different shapes and types of proteins covered with a membrane (e.g. Riccinus communis).

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(a) Mango is a drupe fruit that develops from a monocarpellary, syncarpous, unilocular, and superior ovary. Epicarp of mango fruit forms skin while mesocarp is fleshy and fibrous which is the edible part of this fruit. Endocarp is hard and stony.

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(a) Cuscuta, commonly known as dodder or amarbel, is a parasitic plant. It belongs to order Solanales and family-Convolvulaceae.

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(d) Brinjal or Solanum melongena belongs to the family solanaceae. The fruits are rich in iodine. They are used in the form of vegetables. Gynoecium is bicarpellary, and syncarpous, forming a superior bilocular ovary. Each locule has many ovule on axile placentation. Members of Solanaceae are characterised by the presence of an obliquely placed septum in the ovary and highly swollen placentae. The oblique septum is probably due to shifting in the position of the ovary.

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(a) In tetradynamous condition there are six stamens, 4 are long and 2 are short i.e., \(4+2\) arrangement of stamens. It is the characteristic feature of Cruciferae members. In Liliaceae 6 stamens are arranged in whorls of 3 each \((3+3)\). In Solanaceae, there are 5 stamens that are epipetallous and polyandrous. In Malvaceae, there are numerous stamens that are monadelphous.

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(a) Axillary bud is the bud arising in the axil of the branch. The apical bud arises at the apex. Adventitious bud arises from any location other than its usual location.

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(c) Banana is a berry. It develops from the monocarpellary or multicarpellary syncarpous ovary. Epicarp makes the rind of the fruit, mesocarp is fleshy and endocarp is thin and membranous. The edible portion of banana is endocarp and less developed mesocarp.

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(c) Malvaceae is also known as cotton family or mallow family. The plants of this family are cosmopolitan in distribution, although more common in tropical (warm) regions. Gossypium (cotton) is an important genera of this family.

Sunflower belongs to the family Compositae. Wheat belongs to the family Poaceae. Catechu belongs to the family Mimosaceae.

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(b) Sunflower belongs to Asteraceae (Compositae), orange to Rutaceae wheat to Poaceae (Gramineae) while cotton (Gossypium) belongs to Malvaceae.

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(a) These special roots, called pneumatophores or knees, develop in mangrove plants, i.e., plants growing in saline marshes. These roots grow vertically upward and are negatively geotropic. Air enters these roots through minute breathing pores called pneumathodes, present on the tips of vertical roots. These plants include Rhizophora, Heritiera, Avicinnia, etc., and are found in the Sundarbans of West Bengal.

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(b) The arrangement of ovules inside the ovary of a flowering plant is called placentation. In marginal placentation, the ovule develops from a longitudinal suture where the margins of the ovary wall fuse. e.g. Pea, gram. In apical placentation, a single ovule is born near the apex of the ovary. Here ovary is unilocular (Cannabis). In superficial placentation, the ovary is unilocular simple, or syncarpous e.g. Nymphaea.

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(b) Floral features are used to identify because reproductive parts are more stable and conservative than vegetative parts.

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(b) Sunflower is a dicotyledonous plant. Hence its embryo has two cotyledons. Plants like maize are monocotyledonous and hence have a single cotyledon in the embryo.

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(d) Development of fruits without fertilization is called parthenocarpy and such fruits are called parthenocarpic fruits. Since in pomegranate juicy testa is the edible part and parthenocarpy will make the fruit seedless and hence they will be useless.

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(a) A fruit is a ripened ovary. On the basis of the formation of fruits, they are classified into two types – true fruits and false fruits. True fruits are developed from the ovary only. Banana is a fleshy fruit – berry. It develops from multicarpellary syncarpous superior or inferior ovary. The pericarp of berries is differentiated into epicarp, mesocarp, and endocarp (like drupes) but the endocarp is not stony as in drupes. Apple and pear are pome. Pome is a false fruit in which the edible part is the thalamus where the true fruit remains embedded. Fig is a composite fruit. These fruits are the products of the whole inflorescence together with its component parts.

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(d) Coconut is a true fruit, when fruit develops from the ripened ovary, it is called true fruit as in the majority of fruits. A false fruit develops from any part of the flower except the ovary, e.g. apple, pear, cashewnut, and all composite fruits (mulberry, pineapple).

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(a) In angiosperms, seeds are produced inside the ripened ovary called fruit. However, in gymnosperms, the seeds are not produced inside a fruit. In angiosperms, vascular tissue includes both tracheids and vessels and in gymnosperms, the vascular tissue contains only tracheids and not vessels. Tap root is the primary root that develops from the radicle. It forms lateral branches which are further branched to form tertiary roots. These are generally found in dicotyledons. In monocotyledons, the primary root is short-lived, tap root is absent and adventitious roots are found. The given description is about angiospermic dicot.

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(d) In mango, coconut, plum, etc. the fruit is known as a drupe(stony fruit). They develop from monocarpellary, and superior ovaries, and are one-seeded. In mango, the pericarp is well-differentiated into an outer thin epicarp, a middle fleshy edible mesocarp, and an inner stony hard endocarp.

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(b) Dicotyledoneae is the group of angiosperm with two cotyledons, flower bi or pentamerous, leaves net-veined, stem with open collateral vascular bundle arranged in a ring, and roots form tap root system.

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(a) Pulses are obtained from Fabaceae. Pulses are very economical as well as nutritionally very important for human beings.

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(a) Epipetalous stamens with free filaments and fused anthers occur in Asteraceae. Asteraceae possess five stamens with free filaments. This family shows syngenesious condition in which anthers are united forming a tube around the style.

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(d) This is the floral formula of tobacco. It belongs to the family Solanaceae. The flower is actinomorphic, bisexual, 5 sepals gamosepalous, 5 gamopetalous corolla, 5 epipetalous stamens, and 2 carpels syncarpous having a superior ovary.

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(b) Flowers in pea have diadelphous stamens. The floral formula for Solanaceae is 

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(d) Syngenesious condition is found in Asteraceae. It is the condition when stamens are united by their anthers (filaments free). Epipetalous condition is also seen here.

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(b) Drupe is a fleshy one seeded, indehiscent fruit eg. Mangifera indica.

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(b) A family delimited by type of inflorescence is Asteraceae. Asteraceae possess head or capitulum inflorescence, which is racemose and is surrounded by an involucre of bracts.

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(a) When stamens are united by their anthers and filaments are free the condition is called syngenesious. It is found in the family Asteraceae (Compositae). The condition is an adaptation for entomophily.

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(c) Vegetative reproduction in Agave occurs through bulbils. Bulbils are the specialised buds vegetative or floral that modify into a swollen structure. It separates from the parent plant and on approach of favourable conditions gives rise to the new plant.

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(a) Asteraceae possess five stamens with free filaments but anthers are united forming a tube around the style (syngenesious).

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(d) In groundnut the food/oil reserve is present in cotyledons. It is a very important commercial crop of Leguminosae.

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(c) Outer protective covering of the seed is called seed coat which develops from integuments of ovules. The seeds developing from the bitegmic ovule have two layers. The outer layer is called testa and the inner layer or tegmen develops from inner integuments.

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(b) Cotyledons are the leaves of embryo, usually, store food for the use of the embryo during development. Groundnut, a dicot stores food in the form of oil reserves in the cotyledons.

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(b) Sucker is the subaerial modification of stem, which originates from the basal and underground portion of the main stem but it grows obliquely upwards and gives rise to leafy shoot or a new plant, e.g. Musa(banana), Chrysanthemum, mint.

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(b) Mesocarp is the edible part of Mangifera indica (Mango).

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(a) Coconut (Cocos nucifera) is commercial fibres yielding crop. Fibres originate from the upper epidermal surface of the seed.

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(c) Micropyle of seed is involved in the passage of water. Micropyle plays a very important role in absorbing water during the time of germination.

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(a) Fruit of groundnut is legume. It is developed from monocarpellary ovary but dehisces by both sutures from apex downward.

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(b) Normally endosperm formation is accompanied by degeneration of nucellus. Persistent nucellus is termed as perisperm. The dust-like seeds of orchids have no endosperm. Orchid seedlings are mycoheterotrophic in their early development. In some other species, such as coffee, the endosperm also does not develop. Instead, the nucellus produces a nutritive tissue termed perisperm.

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(c)

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(d)