CBSE Class 12 Biology Sexual Reproduction in Flowering Plants Assignment

Important Questions for NCERT Class 12 Biology Sexual Reproduction in Flowering Plants

Question. From outer to inner what is the sequence of wall layers in anther lobes?
(a) Epidermis, middle layers, tapetum, endothecium
(b) Epidermis, endothecium, tapetum, middle layers
(c) Epidermis, endothecium, middle layer, tapetum
(d) Tapetum, middle layers, endothecium, epidermis
Answer : C

Question. Due to which of the following chemical deposition pollen grains are well preserved as fossils
(a) Pollenkitt
(b) Callose
(c) Sporopollenin
(d) Pectocellulose
Answer : C

Question. Which of the following is not involved in post fertilisation events
(a) Endosperm and embryo development
(b) Maturation of ovules into seed
(c) Maturation of ovary into fruit
(d) Degeneration of nucellus
Answer : D

Question. The structure in which few leaf primordia and shoot apex of monocot embryo remain enclosed is
(a) Coleoptile
(b) Coleorhiza
(c) Epiblast
(d) Epicotyl
Answer : A

Question. Which of the following is not a pollen grain caused disease?
(a) Asthma
(b) Bronchitis
(c) Hayfever
(d) Malaria
Answer : D

Question. The number of ovules in an ovary may be
(a) One
(b) Many
(c) Two
(d) One to many
Answer : D

Question. Each ovule has one or two protective envelopes called
(a) Micropyle
(b) Integuments
(c) Hilum
(d) Chalaza
Answer : B

Question. Regarding to number of ovules in ovary select out the odd one
(a)Wheat
(b) Orchids
(c) Paddy
(d) Mango
Answer : B

Question. What would be the genetic nature of apomictic embryo?
(a) n
(b) 3n
(c) 2n
(d) n or 2n like mother plants
Answer : D

Question. Five kingdom system of classification suggested by R.H. Whittaker is not based on
(a) presence or absence of a well defined nucleus
(b) mode of reproduction
(c) mode of nutrition
(d) complexity of body organisation.
Answer: D

Question. Maximum nutritional diversity is found in the group
(a) fungi
(b) animalia
(c) monera
(d) plantae. 
Answer: A

Question. In the five kingdom classification, Chlamydomonas and Chlorella have been included in
(a) protista
(b) algae
(c) plantae
(d) monera. 
Answer: B

Question. In which kingdom would you classify the archaea and nitrogen-fixing organisms, if the five kingdom system of classification is used ?
(a) Plantae
(b) Fungi
(c) Protista
(d) Monera 
Answer: D

Question. In five kingdom system, the main basis of classification is
(a) structure of nucleus
(b) mode of nutrition
(c) structure of cell wall
(d) asexual reproduction.
Answer: B

Question. In the five kingdom system of classification, which single kingdom out of the following can includeblue-green algae, nitrogen fixing bacteria and methanogenic archaebacteria?
(a) Plantae
(b) Protista
(c) Monera
 (d) Fungi
Answer: C

Question. BGA (blue green algae) are included in which of the following groups?
(a) Bryophytes
(b) Prokaryotes
(c) Protista
(d) Fungi 
Answer: D

Question. An important criterion for modern day classification is
(a) resemblances in morphology
(b) anatomical and physiological traits
(c) breeding habits
(d) presence or absence of notochord. 
Answer: D

Question. Match the organisms in column-I with habitats in column-II.
Column-I                           Column-II
A. Halophiles                     (i) Hot springs
B. Thermoacidophiles       (ii) Aquatic environment
C. Methanogens                (iii) Guts of ruminants
D. Cyanobacteria              (iv) Salty area
Select the correct answer from the options given below.
(a) A-(iv), B-(i), C-(iii), D-(ii)
(b) A-(i), B-(ii), C-(iii), D-(iv)
(c) A-(iii), B-(iv), C-(ii), D-(i)
(d) A-(ii), B-(iv), C-(iii), D-(i) 
Answer: B

Question. Which of the following are found in extreme saline conditions?
(a) Eubacteria
 (b) Cyanobacteria
(c) Mycobacteria
(d) Archaebacteria
Answer: A

Question. Which among the following are the smallest living cells, known without a definite cell wall, pathogenic to plants as well as animals and can survive without oxygen?
(a) Pseudomonas
(b) Mycoplasma
(c) Nostoc
 (d) Bacillus 
Answer: B

Question. Which of the following components provides sticky character to the bacterial cell?
(a) Nuclear membrane
(b) Plasma membrane
(c) Glycocalyx
(d) Cell wall 
Answer: A

Question. DNA replication in bacteria occurs
(a) within nucleolus
(b) prior to fission
(c) just before transcription
(d) during S phase. 
Answer: C

Question. Methanogens belong to
(a) eubacteria
(b) archaebacteria
(c) dinoflagellates
(d) slime moulds.
Answer: B

Question. The primitive prokaryotes responsible for the production of biogas from the dung of ruminant animals, include the
(a) methanogens
(b) eubacteria
(c) halophiles
(d) thermoacidophiles.
Answer: A

Question. Archaebacteria differ from eubacteria in
(a) cell membrane structure
(b) mode of nutrition
(c) cell shape
(d) mode of reproduction. 
Answer: C

Question. Which of the following are likely to be present in deep sea water?
(a) Blue-green algae
 (b) Saprophytic fungi
(c) Archaebacteria
(d) Eubacteria
Answer: C

Question. Pigment containing membranous extensions in some cyanobacteria are
(a) pneumatophores
(b) chromatophores
(c) heterocysts
(d) basal bodies.
Answer: B 

Question. Identify A to E in the diagram given below.

(a) A–Antipodal, B–2 polar nuclei, C–Central cell, D–Egg, E–Synergids
(b) A–Antipodal, B–Central cell, C–2 polar nuclei, D–Egg, E–Synergids
(c) A–2 polar nuclei, B–Central cell, C–Antipodal cell, D–Egg, E–Synergids
(d) A–Synergids, B–Egg, C–Central cell, D–2 polar nuclei, E–Antipodal cell
Answer : D 

Question. In embryo sac, the number of synergid® egg cell→ central cell→ antipodal cell follows the order
(a) 1–1–2–3
(b) 2–1–3–2
(c) 2–1–1–3
(d) 3–2–1–2
Answer : C 

Question. Identify A to F in the diagram given below.

(a) A–Egg, B–Filiform apparatus, C–Synergid,D–Antipodals, E–Polar nuclei, F–Central cell
(b) A–Egg, B–Synergid, C–Filiform apparatus,D–Antipodals, E–Central cell, F–Polar nuclei
(c) A–Central cell, B–Egg, C–Synergid, D–Antipodals,E–Filiform apparatus, F–Polar nuclei
(d) A–Filiform apparatus, B–Synergid, C–Egg, D–Central cell, E–Polar nuclei, F–Antipodals
Answer : D 

Question. Filiform apparatus are
(a) special cellular thickenings at antipodal cell
(b) special cellular thickenings at the micropylar end
(c) special cellular thickenings at synergid cells
(d) special cellular thickenings at nuclear end
Answer : C 

Question. Function of filiform apparatus is to
(a) recognise the suitable pollen at stigma
(b) stimulate division of generative cell
(c) produce nectar
(d) guide the entry of pollen tube
Answer : D 

Question. How many nuclei are found in female gametophyte?
(a) 8
(b) 7
(c) 6
(d) 5
Answer : A 

Question. How many cells are found in female gametophyte?
(a) 6
(b) 8
(c) 7
(d) 5
Answer : C 

Question. Two nuclei within a single cell is
(a) antipodal cell
(b) chalazal cell
(c) central cell
(d) synergid cell
Answer : C 

Question. Egg apparatus consists of
(a) 2 synergids + 2 eggs
(b) 2 synergids + 2 eggs
(c) 2 synergids + 1 egg
(d) 2 synergids + 4 eggs
Answer : C 

Question. In an embryo sac of anatropous ovule, cells present at chalazal end are called
(a) nucellar cells
(b) synergids
(c) antipodal cells
(d) None of these
Answer : C 

Question. In an angiospermic anatropous ovule, the embryo sac contains certain cells at the micropylar end. These are called
(a) synergids
(b) antipodal cells
(c) nucellar cells
(d) None of these
Answer : A  

Pollination 

Question. Autogamy stands for
(a) pollination in same flower
(b) pollination between different plants
(c) pollination in two flowers of same plant
(d) division in embryo
Answer : A 

Question. Cleistogamous flowers are strictly autogamous because they remain
(a) always open
(b) always close
(c) always fragrance
(d) are brighty coloured
Answer : B 

Question. Identify the type of flower A and B.

(a) A–Cleistogamous; B–Chasmogamous
(b) A–Homogamous; B–Heterogamous
(c) A–Chasmogamous; B–Cleistogamous
(d) A–Heterogamous; B–Homogamous
Answer : C 

Question. In chasmogamy pollination takes
place in
(a) open flower
(b) closed flower
(c) large flower
(d) geitonogamy flower
Answer : A 

Question. Advantage of cleistogamy is 
(a) higher genetic variability
(b) more vigorous offspring
(c) no dependence on pollinators
(d) vivipary
Answer : C 

Question. Even in the absence of pollinating agents seed-setting is assured in
(a) Commelina
(b) Zostera
(c) Salvia
(d) Fig
Answer : A 

Question. Geitonogamy involves 
(a) fertilisation of a flower by the pollen from another flower of the same plant
(b) fertilisation of a flower by the pollen from the same flower
(c) fertilisation of a flower by the pollen from a flower of another plant in the same population
(d) fertilisation of a flower by the pollen from a flower of another plant belonging to a distant population
Answer : A 

Question. Transfer of pollen grains from the anther to stigma of another flower of different plant is called
(a) geitonogamy
(b) xenogamy
(c) chasmogamy
(d) cleistogamy
Answer : B 

Question. The most common abiotic pollinating agency in flowering plant is/ are
(a) water
(b) wind
(c) Both (a) and (b)
(d) None of these
Answer : B 

Question. Characteristic of wind pollinated pollens is, they are
(a) non-sticky
(b) light
(c) produced in large number
(d) All of the above
Answer : D 

Question. The feathery long stigma is found in
(a) rice
(b) maize
(c) sugarcane
(d) None of these
Answer : B 

Question. Flowers, which have single ovule in the ovary and are packed into inflorescence are usually pollinated by
(a) water
(b) bee
(c) wind
(d) bat
Answer : C 

Question. Wind pollination is common in 
(a) lilies
(b) grasses
(c) orchids
(d) legumes
Answer : B 

Question. Pollination in water hyacinth and water lily is brought about by the agency of 
(a) water
(b) insects or wind
(c) birds
(d) bats
Answer : B 

Question. What type of pollination takes place in Vallisneria?
(a) Pollination occurs in submerged condition by water
(b) Flowers emerge above surface of water and pollination occurs by insects
(c) Flowers emerge above water surface and pollen is carried by wind
(d) Male flowers are carried by water currents to female flowers at the surface of water
Answer : D 

Question. Pollen grain of water pollinated plants are coated by covering to prevent it from wetting
(a) mucilage
(b) cuticle
(c) exine
(d) intine
Answer : A 

Question. Wind pollinated and water pollinated flowers
(a) are colourful
(b) are non-colourful
(c) are small in size
(d) produce nectar
Answer : B 

Question. Pollenkitt is present in
(a) anemophily
(b) entomophily
(c) malacophily
(d) zoophily
Answer : B 

Question. Attractants and rewards are required for 
(a) anemophily
(b) entomophily
(c) hydrophily
(d) cleistogamy
Answer : B 

Question. Which one of the following plants shows a very close relationship with a species of moth, where none of the two can complete its life cycle without the other?
(a) Banana
(b) Yucca
(c) Hydrilla
(d) Viola
Answer : B 

Question. Continued self-pollination results in
(a) inbreeding depression
(b) out breeding depression
(c) hybrid vigour
(d) better result in offspring
Answer : A 

Question. Device to discourage self-pollination or increase cross-pollination is
(a) pollen release and stigma receptivity are not synchronised
(b) anther and stigma placed at different position
(c) same height of stamen and stigma
(d) Both (a) and (b)
Answer : D 

Question. A dioecious flowering plant prevents both
(a) autogamy and xenogamy
(b) autogamy and geitonogamy
(c) geitonogamy and xenogamy
(d) cleistogamy and xenogamy
Answer : B 

Question. In which of the following, both autogamy and geitonogamy are prevented?
(a) Wheat
(b) Papaya
(c) Castor
(d) Maize
Answer : B 

Question. Identify A to F in the given diagram.

(a) A–Pollen tube, B–Ovary, C–Ovule,D–Antipodal cell, E–Pollen grain,F–Polar nuclei
(b) A–Polar nuclei, B–Antipodal cell,C–Ovule, D–Ovary, E–Pollen tube,F–Pollen grain
(c) A–Pollen grain, B–Pollen tube,C–Ovary, D–Ovule, E–Antipodal cell,F– Polar nuclei
(d) A–Antipodal cell, B–Ovule, C–Ovary,D–Polar nuclei, E–Pollen grain,F–Pollen tube
Answer : C 

Question. Generally pollen tube enters through
(a) micropylar region
(b) antipodal region
(c) chalazal end
(d) nuclear region
Answer : A 

Question. The ability of the pistil to recognise the pollen followed by its acceptance or rejection is the result of a continuous dialogue between pollen grain and the pistil.
Which of the following chemicals mainly takes part in this interaction.
(a) Nucleotides
(b) Proteins
(c) Minerals
(d) Lipid or Inulin
Answer : B 

Question. The process of removal of anther from the flower bud before it dehisces is called as 
(a) emasculation
(b) bagging
(c) embryo rescue
(d) budding
Answer : A 

Question. For artificial hybridisation experiment in bisexual flower, which of the sequence is correct?
(a) Bagging → Emasculation → Cross-pollination → Rebagging
(b) Emasculation → Bagging → Cross-pollination → Rebagging
(c) Cross-pollination → Bagging → Emasculation → Rebagging
(d) Self-pollination → Bagging → Emasculation → Rebagging
Answer : B 

Double Fertilisation and Development of Endosperm 

Question. Double fertilisation is 
(a) fusion of two male gametes with one egg
(b) fusion of one male gamete with two polar nuclei
(c) fusion of two male gametes of pollen tube with two different eggs
(d) syngamy and triple fusion
Answer : D 

Question. Double fertilisation is exhibited by
(a) gymnosperms
(b) algae
(c) fungi
(d) angiosperms
Answer : D 

Question. I. Antipodal cell    II. Egg cell
III. Synergid cell                  IV. Polar nuclei
V. Male gamete                     VI. Nucellar cell
VII. Central cell
Out of the seven names given above, find out haploid cells.
(a) I, II, IV and V
(b) II, IV, VI and VII
(c) I, II, III and V
(d) II, IV, III and I
Answer : C 

Question. What is the fate of the male gametes discharged in the synergid? 
(a) All fuse with the egg
(b) One fuses with the egg, other(s) fuse(s) with synergid nucleus
(c) One fuses with the egg and other fuses with central cell nuclei
(d) One fuses with the egg other(s) degenerate(s) in the synergid
Answer : C 

Question. How many number of nuclei are involved in fertilisation?
(a) 1
(b) 1 + 1
(c) 2 + 1
(d) None of these
Answer : B 

Question. The total number of nuclei involved in triple fusion is/are
(a) 2
(b) 3
(c) 4
(d) 1
Answer : B

POINT TO REMEMBER

Autogamy : When pollen grains of a flower are transferred from anther to stigma of the same flower.

Coleorhiza : A protective sheath of radicle in monocot seed.

Coleoptile : A protective sheath of plumule in monocot seed.

Endothecium : A fibrous layer in the anther next to epidermis.

Geitonogany : Self pollination between flowers of the same plant.

Micropyle : A small pore in the ovule through which the pollen tube enters.

Nucellus : Multicellular tissue in the centre of ovule where embryo sac is present.

Tapetum : Inner most layer of cells in pollen sac which provide nutrition to developing pollen grains

Viability of Seed : Ability of seed to retain the power of germination.

1. Microsporangium (Pollen sac) :
Outermost layer = Epidermis
Second layer = Endothecium
Middle layer = 2 – 4 layers of cells
Innermost layer = Tapetum [Nourishes the developing Pollen grains
(Microspores)]

2. Microsporogenesis : Process of formation of microspores from a pollen mother cell

QUESTIONS

1. In a young anther, a group of compactly arranged homogenous cells were observed in the centre of each microsporangium. What is the name given to these cells?

2. Give the scientific name of a plant which came to India as a contaminant with imported wheat and causes pollen allergy.

3. Pollen grains of water pollinated species have a special characteristics for protection from water. What is that?

4. Why are pollen grains produced in enormous quantity in Maize?

5. In same species of Asteraceae and grasses, seed are formed without fusion of gametes. Mention the scientific term for such form of reproduction.

6. Arrange the following in correct developmental sequence : Male gamete, Potential pollen mother cell, sporogenous tissue, Pollen grains, Microspore tetrad.

7. If the diploid number of chromosomes in an angiospermic plant is 16. Mention number of chromosomes in the endosperm and antipodal cell.

8. In angiospermic plant before formation of microspore sporogenous tissue undergo cell division

(a) Name the type of cell division.

(b) What would be the ploidy of the cells of tetrad?

9. Outer envelop of pollen grain made of a highly resistant substance. What is that substance? At which particular point the substance is not present?

10. Fruits generally develops from ovary, but in few species thalamus contributes to fruit formation.

(a) Name the two categories of fruits.

(b) Give one example of each.

11. Among the animal, insects particularly bees are the dominant pollinating agents. List any four characteristic features of the insect pollinated flower.

12. Differentiate between geitonogamy and xenogamy.

Please refer to the link below for CBSE Class 12 Biology Sexual Reproduction in Flowering Plants Assignment