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Q1. The inner layer of the exine is

• Sexine
• Nexine
• Endosexine
• Tectum

Solution

The exine is made of two major layers—the outer sexine and the inner nexine. The sexine is further divided into the outer tectum and the inner endosexine. The nexine is made of the inner endexine and the outer foot layer.

Q2. Perisperm differs from endosperm in

• Having no reserve food
• Being a diploid tissue
• Its formation by the fusion of secondary nucleus with several sperms
• Being a haploid tissue

Solution

The layer of nutritive tissue derived from the nucellus that surrounds the embryo of a seed in some angiosperms is called perisperm. The perisperm is diploid, while the endosperm is triploid.

Q3. The phenomenon wherein, the ovary develops into a fruit without fertilisation is called

• Parthenocarpy
• Apomixis
• Asexual reproduction
• Sexual reproduction

Solution

Some plants are able to produce fruits without fertilisation. This phenomenon is called parthenocarpy.

Q4. Fusion of a male gamete with an egg in the embryo sac is called

• Triple fusion
• Double fertilisation
• Syngamy
• Autogamy

Solution

One of the male gametes moves towards the egg cell and fuses with its nucleus thus completing syngamy.

Q5. Flowers of Aristolochia smell of

• Human dung
• Decaying tobacco
• Rotten meat
• Honey

Solution

Aristolochia is an entomophilous flower and smells like decaying tobacco.

Q6. What is the function of germ pore?

• Emergence of radicle
• Absorption of water for seed germination
• Initiation of the pollen tube
• Release of male gemetes

Solution

Germ pore acts as the region through which the pollen tube enters the ovary so that the pollen and egg may fuse together to form the zygote.

Q7. When pollen is transferred from anther of a flower to stigma of another flower of the same plant, pollination is referred to

• Geitonogamy
• Allogamy
• Xenogamy
• Siphonogamy

Solution

Allogamy is a type of sexual reproduction in plants in which pollen is transferred from one flower to the stigma of another. Xenogamy is the transfer of pollen grains from the anther to the stigma of a different plant. Siphonogamy is a condition in plants in which the pollen tubes are developed for the transfer of male cells to the egg.

Q8. In the sixteen-cell stage of the embryo in dicots, the eight protodermal cells show which kind of division? 

• Periclinal division
• Anticlinal division
• Transverse division
• Lateral division

Solution

In the sixteen-cell stage of the embryo in dicots, the eight protodermal cells divide further by anticlinal division to form the embryonic surface layer, while the inner eight cells divide in different planes to form the ground meristem and procambium.

Q9. Starting from the innermost part, the correct sequence of parts in an ovule are

• Egg, nucellus, embryo sac and integument.
• Egg, embryo sac, nucellus and integument.
• Embryo sac, nucellus, integument and egg.
• Egg, integument, embryo sac and nucellus.

Solution

The structure of an ovule shows that eggs are the innermost part of the ovule followed by the embryo sac, which contains the egg apparatus, followed by the nucellus, which is surrounded by integuments.

Q10. In double fertilisation

• Two male gametes fuse with two eggs
• One male gamete fuses with the egg and the other fuses with the secondary nucleus
• One male gamete fuses with the egg, while the other fuses with the antipodal
• One male gamete fuses with the antipodal, while the other fuses with the diploid nucleus

Solution

One of the male gametes moves towards the egg cell and fuses with its nucleus thus completing syngamy. This results in the formation of a diploid cell, which is the zygote. The other male gamete moves towards the two polar nuclei located in the central cell and fuses with them to produce a triploid primary endosperm nucleus. This completes the process of double fertilisation.

Q11. In the embryo sac, how many nuclei differentiate to form the antipodal cells?

• 1
• 2
• 3
• 4

Solution

During embryo sac development, four nuclei are found at the chalazal and micropylar ends. Of the four nuclei at the chalazal end, three nuclei differentiate to form the antipodal cells.

Q12. The embryo sac is also known as

• Microgametophyte
• Megagametophyte
• Microsporangium
• Megasporangium

Solution

Embryo sac is also known as the female gametophyte or megagametophyte.

Q13. Endosperm is consumed by a developing embryo in the seed of

• Pea
• Maize
• Coconut
• Castor

Solution

In pea seeds, the endosperm is used up. Such seeds are called exalbuminous seeds.

Q14. Egg apparatus consists of

• Polar nuclei
• Antipodal
• Egg + two synergids
• Nucellus

Solution

The egg apparatus consists of one egg cell (haploid female gamete) and two supporting cells called synergids.

Q15. Eight nucleate embryo sacs are

• Always bisporic
• Always tetrasporic
• Always monosporic
• Sometimes monosporic, bisporic and tetrasporic

Solution

Depending on the number of megaspore nuclei, the development of embryo sac can be monosporic, bisporic or tetrasporic. When only one megaspore nucleus forms the embryo sac, the development of the embryo sac is said to be monosporic. When two megaspore nuclei form the embryo sac, the development of the embryo sac is said to be bisporic. When all the four megaspore nuclei form the embryo sac, the development is said to be tetrasporic.

Q16. The nucleus in some seeds found on the outer side of the endosperm is known as

• Tegmen
• Testa
• Perisperm
• Hypocotyl

Solution

Generally in seeds, the nucleus is used up. However, in certain cases where it is not used up, it forms a thin layer on the outside of the endosperm and is known as the perisperm.

Q17. Entomophilous flowers are pollinated by

• Birds
• Insects
• Wind
• Bats

Solution

Entomophily is pollination by insects.

Q18. In angiosperms, functional megaspore develops into

• Endosperm
• Pollen sac
• Embryo sac
• Ovule

Solution

After megasporogenesis, the megaspore develops into the female gametophyte or the embryo sac in a process called megagametogenesis.

Q19. Triploid tissue in angiosperms is

• Nucellus
• Endosperm
• Endothecium
• Tapetum

Solution

Nucellus is diploid. Endothecium and tapetum may be haploid or diploid.

Q20. The endosperm in angiosperm develops from

• Zygote
• Secondary nucleus
• Chalazal polar nucleus
• Micropyler polar nucleus

Solution

In angiosperms, the endosperm develops from the triploid primary endosperm nucleus which is formed as a result of vegetative fertilisation, triple fusion or fusion of a male gamete with secondary nucleus of the central cell.

Q21. Synergids are

• Haploid
• Diploid
• Triploid
• Tetraploid

Solution

Synergids are the two haploid cells present on the either side of the egg cell at the micropylar end.

Q22. The female gametophyte in angiosperm is

• Carpel
• Ovule
• Embryo sac
• Egg

Solution

The functional megaspore forms the female gametophyte or embryo sac.

Q23. Which one of the following is surrounded by a callose wall?

• Male gamete
• Egg
• Pollen grain
• Microspore mother cell

Solution

The microspore mother cell consists of a callose wall inner to the cell wall. The microspore mother cell undergoes meiosis. It leads to the formation of the microspore tetrad. It is followed by the degeneration of the wall of microspore mother cells to separate pollen grains (microspores).

Q24. Male gametes in angiosperms are formed by the division of

• Microspore mother cell
• Microspore
• Generative cell
• Vegetative cell

Solution

Pollen grains in angiosperms are released at the 2-celled stage—generative cell and vegetative cell. The generative cell divides to form two male gametes.

Q25. In Meiosis-I, the cells always divide along which plane?

• Transverse
• Lateral
• Random
• Longitudinal

Solution

In Meiosis-I, the cells always divide along the transverse plane.

Q26. Micropyle occurs in (1) Seed (2) Ovule (3) Ovary (4) Stigma

• 1, 2 and 3 are correct
• 1 and 2 are correct
• 2 and 4 are correct
• 1 and 3 are correct

Solution

Micropyle occurs in the ovule, and so, ultimately in the seed after fertilisation.  

Q27. Anemophily type of pollination is found in

• Salvia
• Bottle brush
• Vallisneria
• Coconut

Solution

Entomophily occurs in Salvia, Ornithophily occurs in Bottle brush and Hydrophily occurs in Vallisneria.

Q28. Vegetative fertilisation is also called

• Triple fusion
• True fertilisation
• Syngamy
• Generative fertilisation

Solution

Vegetative fertilisation is also called triple fusion because three nuclei get fused which are two polar nuclei and one male gamete.

Q29. Pollen grains of rice and wheat remain viable for

• 24 hours
• 240 hours
• 1 hour
• 0.5 hours

Solution

In case of rice and wheat, the pollen grains remain viable for a very less time, about 30 minutes.

Q30. In some plants, the anthers and stigma grow and mature at the same time. This phenomenon is called

• Homogamy
• Syngamy
• Allogamy
• Fusion

Solution

Anther and stigma of bisexual flowers of some plants mature at the same time. They are brought close to each other to ensure self-pollination. This is called homogamy.

Q31. The ovule found in Opuntia is of which type?

• Amphitropous ovule
• Orthotropous ovule
• Circinotropous ovule
• Campylotropous ovule

Solution

The circinotropous ovule is straight with the micropyle facing upwards. The funicle is elongated and appears coiled shape and completely encircles the ovule. In the beginning, the ovule is orthotropous, but it becomes circinotropous as it develops. This type of ovule is seen in Opuntia flowers.

Q32. Edible part in mango is

• Endocarp
• Receptacle
• Epicarp
• Mesocarp

Solution

The mango fruit is a large, fleshy drupe, containing edible mesocarp of varying thickness.

Q33. Sporopollenin an organic material is present in

• Stigma
• Style
• Exine
• Intine

Solution

Exine is thick, sculptured and smooth. It is cuticularised and the cutin is made of a special type called sporopollenin, which is resistant to the chemical and biological decomposition.

Q34. Yucca is pollinated by

• Colpa aurea
• Tageticula
• Blastophaga
• Wind

Solution

Yucca has a close obligatory symbiotic relation with its insect pollinator Tageticula (a moth).

Q35. In which one of the following is pollination autogamous?

• Geitonogamy
• Xenogamy
• Chasmogamy
• Cleistogamy

Solution

Autogamy is a kind of pollination in which pollen from the anthers of a flower is transferred to the stigma of the same flower. In cleistogamy, flowers never open to expose their sex organs and the pollen fall on the stigma of the same flower, thereby ensuring autogamy.

Q36. Parthenocarpic fruits are developed by the application of

• Auxins and cytokinins
• Cytokinins and gibberellins
• Auxins and gibberellins
• Cytokinins and abscisic acid

Solution

In horticultural techniques, parthenocarpic fruits are artificially developed by the application of low concentration of auxins and gibberellins.

Q37. Among the terms listed below, those that are not technically correct names for a floral whorl are (i) Androecium   (ii) Carpel (iii) Corolla   (iv) Sepal

• (i) and (iv)
• (iii) and (iv)
• (ii) and (iv)
• (i) and (ii)

Solution

A typical angiospermic flower consists of four whorls attached onto the receptacle—calyx, corolla, androecium and gynoecium.

Q38. The type of pollination that brings genetically different types of pollen grains to the stigma of a plant is

• Xenogamy
• Geitonogamy
• Chasmogamy
• Autogamy

Solution

Geitonogamy is a kind of pollination in which pollen from the anther of a flower is transferred to the stigma of another flower borne on the same plant. Chasmogamous flower opens at maturity, exposing stamens and style to allow fertilisation. Autogamy is a kind of pollination in which pollen from the anther of a flower is transferred to the stigma of the same flower.

Q39. Filiform apparatus is a characteristic feature of

• Suspensor
• Egg
• Synergid
• Zygote

Solution

Filiform apparatus is contained in synergids which guides the pollen tube to the egg cell.

Q40. Bud pollination can be observed in? 

• Mirabilis 
• Potato 
• Wheat 
• Catharanthus