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91. What external changes are visible after the last moult of a

cockroach nymph? (A) Anal cerci develop (B) Both for wings and hind wings develop (C) Labium develops (D) Mandibles become harder 92. Which of the following correctly describes the location of some body parts in the earthworm 𝑃ℎ𝑒𝑟𝑒𝑡𝑖𝑚𝑎? (A) Two pairs of accessory glands in 16-18th segment (B) Four pairs of spermathecae in 4-7th segment (C) One pair of ovaries attached at intersegmental septum of 14th and 15th segment (D) Two pairs of testes in 10th and 14th segments

93. If a live earthworm is pricked with a needle in its outer surface without damaging its guts, the fluid that comes out is (A) excretory fluid (B) coelomic fluid (C) haemolymph (D) slimy mucus The coelomic fluid of annelids plays a role in many important functions— e.g., locomotion and regulation of fluid transfer through the body wall (osmoregulation). Many metabolic processes occur in the coelom, which also serves as a site for temporary food storage, for

excretion of nitrogen-containing wastes, and for maturation of gametes. The coelomic walls of earthworms contain cells, called chloragocytes, that store and metabolize oil and glycogen and produce ammonia and urea. The chloragocytes eventually disintegrate in the coelomic fluid, and their granules are taken up by amoebocytes, which increase in size, becoming large brown bodies that are never eliminated from the body.

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94. Earthworm have no skeleton but during burrowing, the anterior end becomes turgid and acts as a hydraulic skeleton. It is due to (A) coelomic fluid (B) blood (C) gut peristalis (D) setae 95. Frogs differ from humans in possessing (A) paired cerebral hemisphere (B) hepatic portal system (C) nucleated blood RBCs (D) thyroid 96. Identify the incorrect statements from the following.

I. Cymose inflorescence found in 𝐻𝑖𝑏𝑖𝑠𝑐𝑢𝑠 sp. II. Hypanthodium is found in 𝐹𝑖𝑐𝑢𝑠 𝑏𝑒𝑛𝑔ℎ𝑎𝑙𝑒𝑛𝑠𝑖𝑠. III. Synandrous stamen is found in 𝐶𝑎𝑙𝑜𝑡𝑟𝑜𝑝𝑖𝑠. IV. Hesperidium type of fruit is mango.

(A) III and IV (B) I and II (C) II and III (D) I and IV A Hesperidium is a berry with a tough, aromatic rind. This is an Orange (Citrus sinensis). Other fruits of this type are all Citrus fruits: Citron (Citrus medica), Grapefruit (Citrus x paradisi), Kumquat (Fortunella), Lemon (Citrus limon), Lime(Citrus aurantifolia).

Synandrous: Anthers as well as the filaments are fused throughout their whole length, eg. Cucurbitaceae In Calotropis, gynostegium is present (formed by the fusion of stigma and androecium). The pollen are arranged in a structure named pollinia which are attached to a glandular, adhesive disc at the stigmatic angle (Translator Mechanism). These sticky discs get attached to the legs of visiting bees so that pollinia are pulled out when the bee moves away. When such a bee visits another flower, this flower gets pollinated by the sticky pollinium. 97. In unilocular ovary with a single ovule, the placentation is (A) marginal (B) basal (C) free central (D) axile

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98. Replum is present in the ovary of flower of (A) lemon (B) mustard (C) sunflower (D) pea

99. Dry indehiscent single seeded fruit formed from bicarpellary syncarpous inferior ovary is (A) caryopsis (B) cypsella (C) berry (D) cremocarp

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100. The fleshy receptacle of synconus of fig encloses a number of (A) achenes (B) samaras (C) berries (D) mericarps A syconium is the type of inflorescence borne by figs (genus Ficus), formed by an enlarged, fleshy, hollow receptaclewith multiple ovaries on the inside surface. In essence, it is really a fleshy stem with a number of flowers, so it is considered both a multiple and accessory fruit. The name comes from the Ancient Greek word sykon, meaning "fig"

The syconium is an urn-shaped receptacle which contains between 50 to 7000 (depending on the species) highly simplified uniovulate flowers or florets on its inner surface. It is closed off from most organisms by the ostiole, formed by bracts.

Syconia can be monoecious or functionally dioecious: the former contain female flowers with variable style length and few male flowers, and produce seeds and pollen. The latter have male and female forms in different plants: seed figs contain female flowers with long styles and produce seeds; gall figs contain female flowers with short styles and male flowers and produce pollen.

Once pollinated, the florets develop into achenes or drupes, in which the seeds are enclosed by a layer of endocarp. From this perspective, the fig is an enclosure with tens to thousands of fruits within it.

Syconus: This is the other type of multiple fruit which develops on the ripening of the hypanthodium or the coenanthium inflorescence. In Ficus

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plants or figs, the female flowers within the closed receptacle (rachis) of the inflorescence develop achenes giving rise to a multiple fruit of achenes.

101. The fruit is chambered, developed from the inferior ovary and has seed with succulent testa is (A) pomegranate (B) orange (C) guava (D) cucumber pomegranate. A deciduous shrub or small tree (Punica granatum) native to Asia and widely cultivated for its edible fruit. The fruit of this tree, having a tough reddish rind and containing numerous seeds surrounded by tart juicy red pulp.

102. Composite fruit is present in (A) pear (B) mulberry (C) lotus (D) strawberry

Multiple or Composite Fruits: While aggregate fruits are formed out of a number of free ovaries within a single flower, the multiple or composite fruit is formed by all the flowers of a whole inflorescence grouped together.

Sorosis: In this type the rachis and all the floral part of a spadix type of inflorescence fuse together forming a composite fruit. In jack-fruit (Artocarpus heterophyllus of Moraceae—Fig. 458A), the thick club-shaped rachis has the flowers arranged on it.

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The fertile fruits have edible, juicy perianth leaves and the bracts form more or less juicy chaffs around them. The spines on the tough rind represent the stigmas of the carpels.

Each seed, which is also edible, is covered by a membranous testa. Pandarus of Pandanaceae has got a multiple fruit somewhat similar to jack-fruit.

In pineapple (Ananas comosus of Brome- liaceae)— there is a similar structure but the ovaries are not so conspicuous, the edible portion being formed more by the rachis, perianth and bracts. Small seeds may be found. Each polygonal area on the surface represents a flower. The mulberry (Morns indica of Moraceac)— has a similar fruit in which the fleshy perianths enclose dry achenes.

103. Filament attached along the whole length of anther is the condition called (A) adnate (B) dorsifixed (C) basifixed (D) versatile

Fixation of anthers

• The mode of attachment of the anther to the filament varies greatly in flowers. It is of following types:

– Basifixed or innate: Here the filament is attached to the base of the anther, as in mustard, Datura,

radish.

– Adnate : Here the filament is fixed to the anther in such a manner that it runs up the entire length of

the anther at its backside, e.g., Magnolia, Ranunculus, Nymphaea.

Dorsifixed : The filament is fixed to the dorsal side or back of the anther and anther is immovable,

e.g., Hibiscus rosasinensis, Passiflora, Sesbania, etc.

Versatile : The filament is attached to the middle of the connective so that anther lobes can swing on it

freely. e.g., grasses.

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104. Schizocarpic fruit has (A) fleshy pericarp (B) origin from inflorescence (C) origin from apocarpous pistil (D) trait of breaking up into single seeded parts Separating follicles which are dry, dehiscent fruits derived from one carpel, splitting along one suture, as in Apocynaceae. Schizocarpic Mericarps, Cremocarp, or Carpopodium. Separating mericarps which are dry, seed-like fruits derived from an inferior ovary, as in the Apiaceae.

Schizocarpic or Splitting Fruits: These fruits maybe considered intermediate between achenial (being indehiscent) and capsular (being many seeded) fruits. The fruit breaks up into a number of indehiscent single-seeded segments called mericarps from which seeds are liberated only when pericarp gets rotten. In some cases one- seeded parts of the fruit are dehiscent and are called Cocci.

Schizocarpic fruits are of following 5 types: 1. Lomentum: The fruit is constricted between the seeds and usually breaks up into segments containing one or more seeds, e.g. Mimosa, Acacia arabica (Fig. 7.6). In case of radish, the fruit is lomentaceous siliqua.

2. Compound Samara: This is a type of two or more-chambered fruit derived from a syncarpous (i.e., compound) ovary. The pericarp is extended in the form of wings and at maturity the fruit breaks up % into single seeded mericarps. e.g., EIm (Holoptelea), maple (Fig. 7.7).

3. Cremocarp: This is a two-seeded fruit derived from bicarpellary, syncarpous, inferior, bilocular and uniovuled ovary. It is a typical fruit of family umbelliferae. The two mericarps split along the central axis or

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carpophore to which they remain attached. Persistent style and stylopodium are present e.g. Coriander. (Fig. 7.8).

4. Carcerulas: This fruit is derived from superior, syncarpous pistil, multilocular with axile placentation. The fruit splits into many mericarps. e.g. Hollyhock (Althaea rosea), Salvia, Ocimum (Fig. 7.9).

5. Regma: It is derived from polycarpellary pistil which splits into as many Cocci (dehiscent segments) as there are carpels. Regma of castor breaks up into three cocci as it is derived from tricarpellary syncarpous pistil. Similarly, regma of Geranium breaks into five cocci as it is derived from five carpels (Fig. 7.10).

105. Milky water in green coconut is (A) liquid female gametophyte (B) liquid endosperm (C) liquid nucellus (D) liquid chalaza

Coconut water is the clear liquid inside young green coconuts (fruits of the coconut palm). In early development, it serves as a suspension for the endosperm of the coconut during the nuclear phase

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of development. As growth continues, the endosperm matures into its cellular phase and deposits into the rind of the coconut meat.

Directions (106-120) In the following questions, more than one of the answer given may be correct. Select the correct answer and mark them according to the codes given below. Codes (A) 1, 2 and 3 correct (B) 1 and 2 correct (C) 2 and 4 correct (D) 1 and 3 correct 106. The stem tendrils are modified extra-axillary branches in (1) 𝐶𝑢𝑐𝑢𝑟𝑏𝑖𝑡𝑎 (2) 𝑂𝑝𝑢𝑛𝑡𝑖𝑎 (3) 𝐿𝑢𝑓𝑓𝑎 (4) 𝑁𝑒𝑟𝑖𝑢𝑚

Ans d Stem tendrils: Stem or its branches get modified into green thread like leafless structures called tendrils which are meant for climbing. These may be branched or un-branched. A scale leaf is always present at the point of branching of the tendril.

Extra-axillary tendrils-e.g., Cucurbita, Luffa 107. Tap root system

(1) is always underground (2) is produced by the radicle of the embryo (3) consists of a single primary root (4) consists of roots forming a cluster Ans a

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108. Respiratory roots (1) are assimilatory roots which develop in plants growing in diverse habitats (2) help in the exchange of gases with the help of pneumathodes or lenticels (3) do not possess any definite organ for the exchange of gases (4) develop in plants growing in mangroves or swamp near sea-shores Ans:c Roots are found in plant growing in mangroves or swamps near the sea-shore. Pneumatophores arise vertically upwards and come out of soil and water. They bear small pores called pneumatothodes or lenticels for exchange of gases, e.g. Heritiera.

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109. The main functions of stem are that (1) it bears and supports foliage, flowers and fruits (2) it store food in their aerenchyma cells (3) it adds new cells, tissues and organs every year to keep continuing the functioning of the plant for long period of time (4) leaf-like, flattened, modified stems are called the thallus Ans d 110. Leaf-like structure formed by the stem modification, is called phylloclade, which (1) originates in the axil of a leaf that usually falls off leaving a scar (2) can bear leaves, branches, flowers, etc. (3) an axillary bud present in the axil of a phyllode (4) usually does not store water and food Ans b

"phylloclade" to refer a portion of a leaf-like stem or branch with multiple nodes and internodes, and "cladode" for a single internode of a phylloclade.

Although phylloclades are usually interpreted as modified branches, developmental studies have shown that they are intermediate between leaves and branches as their name indicates.

Phylloclades: These are fleshy, green flattened or cylindrical branches of unlimited growth. The leaves are modified into spines or scales to check transpiration. They take part in photosynthesis and store water. These

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are seen in xerophytic plants like Opuntia, Euphorbia, Casuarina, Cocoloba etc.

111. The compound umbel type of inflorescence is found in (1) 𝐶ℎ𝑟𝑦𝑠𝑎𝑛𝑡ℎ𝑒𝑚𝑢𝑚 (2) 𝐻𝑦𝑑𝑟𝑜𝑐𝑜𝑡𝑦𝑙𝑒 (3) 𝐻𝑒𝑙𝑖𝑎𝑛𝑡ℎ𝑢𝑠 𝑎𝑛𝑛𝑢𝑢𝑠 (4) 𝑃𝑟𝑢𝑛𝑢𝑠 𝑐𝑒𝑟𝑎𝑠𝑢𝑠

Ans c Hydrocotyle umbellata, Many-flowered Pennywort The inflorescence is a simple umbel.

Umbel: In this inflorescence the primary axis remains comparatively short, and it bears at its tip a group of flowers which possess pedicels or stalks of more or less equal lengths so that the flowers are seen to spread out from a common point. In this inflorescence a whorl of bracts forming an involucre is always present, and each individual flower develops from the axil of a bract.

Generally the umbel is branched and is known as umbel of umbels (compound umbel), and the branches bear flowers, e.g., in coriander (Coriandrum sativum), fennel, carrot, etc. Sometimes, the umbel is un-branched and known as simple umbel, e.g., Brahmi (Centella

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asiatica). This inflorescence (umbel) is characteristic of Apiaceae (Umbelliferae) family.

112. Spikelet is compact type of inflorescence, in which (1) few flowers are contained by an axis, rachilla (2) at the base of each flower is the fertile glume or lower palea or lemma (3) slightly above of lemma is a glume called palea (4) at the place of origin of flower, a whorl of bracts called involucre is always present Ans a

Spikelets: Each spikelet may bear one to several flowers (florets) attached to a central stalk known as rachilla. Spikeletes are arranged in a spike inflorescence which is composed of several to many spikelets which are combined in various manners on a main axis called the rachis. Some are in compound spikes (i.e., in wheat—Triticum aestivum), others are in racemes (e.g., in Festuca), while some are in panicles

(e.g., i n Avena).

113. Valvate type of aestivation of calyx is found in (1) 𝑆𝑜𝑙𝑎𝑛𝑢𝑚 (2) 𝐼𝑏𝑒𝑟𝑖𝑠 𝑎𝑚𝑎𝑟𝑎 (3) mustard (4) 𝐷𝑖𝑎𝑛𝑡ℎ𝑢𝑠 Ans d

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Mostly annual herbs (Solanum nigrum), undershrubs (Solanum melongena). Gamosepalous, persistent (in the fruit condition also) valvate aestivation.

Aestivation of Corolla and Calyx: Aestivation is the mode of arrangement of sepals or petals in relation to one another in a floral bud. It is useful in classification and identification of plants.

It is of following types: (i) Valvate: The edges of sepals or petals touch or most not ‘ouch each other but do not overlap, e.g., mustard, coriander etc.

(ii) Twisted (contorted): One edge of petal or sepal regularly overlaps the margin of the next one, e.g., petals of china rose.

(iii) Imbricate: The overlapping becomes irregular. Out of five members, one is outer, one is inner and the rest three remain in twisted condition.

114. A flower is called haplochlamydeous if it (1) contains both androecium and gynoecium (2) lacks sepals (3) contains both sepals and petals (4) lacks petals Ans c Definition of homochlamydeous. : having a perianth whose inner and outer series are similar or not differentiated into calyx and corolla <the lily has a typical homochlamydeous perianth. ae 115. Flowers of which of the following plant sets are zygomorphic? (1) 𝐴𝑑ℎ𝑎𝑡𝑜𝑜𝑑𝑎 and pea (2) Larkspur and 𝑂𝑐𝑖𝑚𝑢𝑚 (3) Mustard and onion (4) Brinjal and pea Ans b

Irregular or zygomorphic

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papilionaceous

poppy-family flowers have four petals arranged in two whorls, such as the poppy.

rose-family flowers are regular flowers with five petals, like the wild rose.

cruciform flowers are regular flowers with four petals cross-shaped.

papilionaceous flowers are very peculiar irregular. The present 5 petals. One at the top, called standard or banner; two side ones, called wings, and two joined ones below which form the keel.

Larkspur Flowers are irregularly shaped and bloom in a loose, vertical grouping along the upper end of the plant's main stalk.

It is a strap-shaped, zygomorphic, gamopetalous corolla, with a short, narrow tube. They appear to be divided into two separate lips, e.g., Adhatoda, Ocimum.

116. A pair of large, thick, muscular and rhythimically contractile vertical vessels called hearts, are present in each of the segments (1) 7 (2) 9 (3) 12 (4) 15

CLASS XI BIOLOGY T8

Ans a 117. Which of the following match is correct in earthworm? (1) Pharynx − 1st segment (2) Stomach − 9th to 14th segment (3) Gizzard − 26th segment (4) Mouth − 1st segment Ans c

118. Which of the following statements are not correct regarding earthworm? (1) Brown or clay coloured skin of the earthworm is due to presence of pigment haemocyanin (2) Chloragogen cells are yellow cells conserved with storage of reserve food, deamination of proteins, formation of urea and also excretory (3) Setae and contraction of muscles help in digestion (4) Dorsal blood vessels is distributive in segments 1 to 13 Ans d The locomotion is brought about by an increase in the hydrostatic pressure of the anterior ten segments of the body and at the same time contraction of circular muscles begins at the anterior end and the wave passes backwards, resulting the anterior region to extent forward. The anterior end grips the substratum and setae act as anchors on the soil. Then the circular muscles relax

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and longitudinal muscles of the anterior segments contract in a wave beginning from the anterior end, which shortens the anterior end and causes the posterior part of body to pull forward. The alimentary canal is a straight tube. Mouth opens into buccal cavity that leads into pharynx in segments 3 and 4, followed by oesophagus that leads to a thick-walled, muscular gizzard in which food is ground by muscular contractions. The salivary glands secrete mucin which lubricates food and protease which digests proteins. The stomach lies in segments 9-14. The wall of the stomach carries calciferous glands that neutralize humic acid. The intestine is wide tube and is divided into pretyphlosolar region in segments 15-26 and post-typhlosolar region after segment 26. The role of the typhlosole is to increase the surface of absorption. Intestinal caeca in segment 26 carry digestive glands which secrete digestive enzymes. The glandular cells of intestine secrete pepsin, trypsin, amylase, lipase and cellulase. Undigested food and soil are eliminated through anus to the outside in the form of castings.

An adult worm measures about 15-30 cm in length and is dark brown in colour due to the presence of a pigment porphyrin in its skin.

Porphyrins are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). The parent porphyrin is porphin, and substituted porphines are called porphyrins.

Structure of porphin, the simplest porphyrin 119. Respiratory system of cockroach (1) consists of tracheae, tracheoles and spiracles (2) are coordinated and regulated by nerve centres in thoracic ganglia which are stimulated by low O2 and higher CO2 concentration in tissue fluids (3) Contains mainly four types of cells trophocytes, mycetocytes, oenocytes and urate cells (4) is open or lacunar type Ans: b

Respiratory System The respiratory system consists of a network of trachea, that open through 10 pairs of small holes called spiracles present on the lateral side of the body. Thin branching tubes (tracheal tubes subdivided into tracheoles) carry oxygen from the air to all the parts. The opening of the spiracles is regulated by the sphincters. Exchange of gases take place at the tracheoles by diffusion.

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120. Sense organs in cockroach are (1) photoreceptors (2) thermoreceptors (3) auditory receptors (4) cenocytes Ans a

SENSE ORGANS OF PERIPLANETA AMERICANA In cockroach , various structures like antennae , labium , maxillary palps, labialpalps , compound eyes , simple eyes etc., are sensory in nature .

Sensory structures

1. Thigmoreceptors: They are receptors of touch. Thigmoreceptors are present on body, antenna, maxillary palps and legs.

2. Olfactory receptors: They receive various smells. Olfactory receptors are present on antenna and palps.

3. Gustatory receptors: They are for sense of taste. Gustatory receptors are present on maxilla and labial palps.

4. Thermoreceptors- detect changes in temperature, present on the pads between the first four tarsals.

5. Auditory receptors- for hearing, present on the anal cerci respond to air or earth borne vibrations.