1. Sexual reproduction involving the fusion of two cells in Chlamydomonas is
(a) isogamy
(b) homogamy
(c) somatogamy
(d) hologamy
Answer and Explanation:
1. (d): Isogamy involves the fusion of gametes which are morphologically and physiologically similar. They are called isogametes. In Chlamydomonas, two vegetative cells may fuse to form a zygospore and the phenomenon is called as hologamy. As a result of fusion of two gametes, zygospore is formed.
2. Prothallus (gametophyte) gives rise to fern plant (sporophyte) without fertilization. It is
(a) apospory
(b) apogamy
(c) parthenocarpy
(d) parthenogenesis.
Answer and Explanation:
2. (b): Prothallus (gametophyte) gives rise to fern plant (sporophyte) without fertilization. This phenomenon is called apogamy. Development of sporophyte from gametophyte without forming gamete is apogamy. Such sporophyte is haploid in nature.
3. In P/rtHs/Cyccw/gymnosperms, the endosperm is
(a) triploid
(b) haploid
(c) diploid
(d) tetraploid.
Answer and Explanation:
3. (b): In Pmz/.v/Cyca.v/gymnosperms the endosperm is haploid because it is produced before fertilization.
4. An evolutionary important character of Selaginella is
(a) heterosporous nature
(b) rhizophore
(c) strobili
(d) ligule.
Answer and Explanation:
4. (a): Evolutionary important character of Selaginella is heterosporous nature. Selaginella produces two types of spores microspores and megaspores. Heterospory in the life cycle of Selaginella leads to the formation of seed habit.
5. Sperms of both Funaria and Pteris were released together near the archegonia of Pteris. Only its sperms enter the archegonia as
(a) Pteris archegonia repel Funaria sperms
(b) Funaria sperms get killed by Pteris sperms
(c) Funaria sperms are less mobile
(d) Pteris archegonia release chemical to attract its sperms.
Answer and Explanation:
5. (d): Sperms of both Funaria and Pteris were released together near the archegonia. But only the sperms of Pteris enter the archegonia, as Pteris archegonia release a chemical malic acid to attract its sperms for fertilization.
6. In F/Vws/gymnosperms, the haploid structures are
(a) megaspore, endosperm and embryo
(b) megaspore, pollen grain and endosperm
(c) megaspore, integument and root
(d) pollen grain, leaf and root.
Answer and Explanation:
6. (b): In Pinus gymnosperms, endosperm is produced before fertilization and hence it is haploid. Megaspore and pollen grains are structures of male gametophytes and it is also haploid.
7. Apophysis in the capsule of Funaria is
(a) lower part
(b) upper Part
(c) middle part
(d) fertile part.
Answer and Explanation:
7. (a): Apophysis is basal portion of capsule in continuation with seta. The outer layer of apophysis is epidermis which has stomata for gaseous exchange. In capsule of Funaria stomata are present only in apophysis.
8. Moss peristome takes part in
(a) spore dispersal
(b) photosynthesis
(c) protection
(d) absorption.
Answer and Explanation:
8. (a): Moss peristome is present in capsule and takes part in spore dispersal. The hygroscopic action of peristomial teeth help in the removal of operculum. The lengthening and shortening of peristomial teeth help in the dispersal of spores. The inner peristome acts as a sieve allowing only a few spores to escape at a time.
9. Protonema occurs in the life cycle of
(a) Riccia
(b) Funaria
(c) Anthoceros
(d) Spirogya.
Answer and Explanation:
9. (b): Protonema occurs in the life cycle of Funaria. The spore is the first cell of gametophytic generation and it germinates to form a filamentous branched alga like structure called protonema. If gives rise to new plant.
10. The product of conjugation in Spirogyra or fertilization of Chlamydomonas is
(a) zygospore
(b) zoospore
(c) oospore
(d) carpospore.
Answer and Explanation:
10. (a): The product of conjugation in Spirogyra or fertilization of Chlamydomonas is zygospore. Both are the members of green algae where gametes are fused to form zygote which develops into a thick walled zygospore.
11. The common mode of sexual reproduction in Chlamydomonas is
(a) isogamous
(b) anisogamous
(c) oogamous
(d) hologamous.
Answer and Explanation:
11. (a): In Chlamysomonas sexual reproduction takes place through isogamy, anisogamy, and oogamy, lsogamy is the fusion of similar gametes. Anisogamy is fusion of morphologically similar but physiologically different cells. Oogamy is fusion of different gametes.
12. Which one has the largest gametophyte?
(a) Cycas
(b) angiosperm
(c) Selaginella
(d) moos
Answer and Explanation:
12. (d): Moss has the largest gametophyte. Mosses are small, soft plants that are typically 1-10 cm tall, some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds and their simple leaves cover the thin wiry stem.
13. Bryophytes are amphibians because
(a) they require a layer of water for carrying out sexual reproduction
(b) they occur in damp places
(c) they are mostly aquatic
(d) all the above.
Answer and Explanation:
13. (a): Bryophytes are called the amphibians because they require a layer of water for carrying out sexual reproduction. They grow in the moist places on land but they require water during the time of fertilization i.e. for completion of life cycle.
14. A plant in which sporophytic generation is represented by zygote is
(a) Pinus
(b) Selaginella
(c) Chlamydomonas
(d) Dryopteris.
Answer and Explanation:
14. (c): A plant in which sporophytic generation is represented by zygote is Chlamydomonas. It is a type of algae that has gametophytic plant body (haploid). It reproduces sexually by gametes which are isogametes that fuse to produce diploid zygote which is the only sporophytic generation.
15. The plant group that produces spores and embryo but lacks vascular tissues and seeds is
(a) pteridophyta
(b) rhodophyta
(c) bryophyta
(d) phaeophyta.
Answer and Explanation:
15. (c): Bryophytes are the plants which produce spores and embryos but they do not have vascular tissue system. While rhodophytes and phaeophytes are algae and produce spores (no embryos) only and pteridophytes produce spores, embryo and well developed vascular tissue system.
16. Which one of the following is not common between Funaria and Selaginella?
(a) archegonium
(b) embryo
(c) flagellate sperms
(d) roots.
Answer and Explanation:
16. (d): Root is not common between Funaria and Selaginella. Funaria is a bryophyte and has archegonium, embryo, flagellated sperms which are also present in Selaginella. Selaginella is a pteridophyte and it has a root which is absent in Funaria.
17. A plant having seeds but lacking flowers and fruits belongs to
(a) pteridophytes
(b) mosses
(c) ferns
(d) gymnosperms.
Answer and Explanation:
17. (d): A plant having seed but lacking flowers and fruit belongs to gymnosperms. Gymnosperms are vascular land plants and bear seeds which are naked i.e., ovules not enclosed in the ovary. Hence, flowers are absent.
18. In Pinus, the pollen grain has 6 chromosomes than in its endosperm will have
(a) 12
(b) 18
(c) 6
(d) 24
Answer and Explanation:
18. (c): In Pinus, if the pollen grain has 6 chromosomes then in its endosperm will also have 6 chromosomes as endosperm and pollen grains are both haploid structures.
19. Resin and turpentine are obtained from
(a) Cycas
(b) Pinus
(c) Cedrus
(d) Abies.
Answer and Explanation:
19. (b): Resins and turpentine are obtained from Pinus which is gymnospermic plant. Cycas is an ornamental plant. Paper and Canada balsam are obtained from Abies and timber are obtained from Cedrus deodara.
20. Turpentine is got from
(a) angiospermous wood
(b) bryophytes
(c) gymnospermous wood
(d) ferns.
Answer and Explanation:
20. (c): Turpentine is commercially very important. It is obtained from Pinus which is a member of gymnosperm. It is obtained from Abies balsamea.
21. Pteridophytes differ from mosses/bryophytes in possessing
(a) independent gametophyte
(b) well developed vascular system
(c) archegonia
(d) flagellate spermatozoids.
Answer and Explanation:
21. (b): Pteridophytes differ from mosses/bryophytes in having well developed vascular tissue system. In mosses/ bryophytes vascular tissue is absent.
22. In Ulothrix/Spirogyra, reduction division (meiosis) occurs at the time of
(a) gamete formation
(b) zoospore formation
(c) zygospore germination
(d) vegetative reproduction.
Answer and Explanation:
22. (c): In UlothrixISpirogyra reduction division (meiosis) occurs at the time of zygospore formation. Plant body of Ulothrix and Spirogyra is gametophytic (haploid), they produce zoogametes (n) which fuses to form zygosporic (2n) diploid, which is a resting spore. Onset of favourable condition zygospore undergoes reductional division, or meiosis to produce zoo- meiospores.
23. The chloroplast of Chlamydomonas is
(a) stellate
(b) cup-shaped
(c) collar-shaped
(d) spiral.
23. (b): Chloroplast in Chlamydomonas is cup-shaped. It is one celled structure. Whereas stellate, spiral and collar shaped chloroplasts are present in Zygnema, Spirogyra and Ulothrix respectively.
24. Pteridophytes differ from bryophytes and thallophytes in having
(a) vascular tissues
(b) motile antherozoids
(c) archegonia
(d) alternation of generations.
Answer and Explanation:
24. (a): Pteridophytes differs from bryophytes and thallophytes in having well developed vascular tissue system. Vascular tissue plays an important role in conducting water and food materials to the plants. Whereas these are absent in bryophytes and thallophytes.
25. Pyrenoids are the centres for the formation of
(a) Porphyra
(b) enzymes
(c) fat
(d) starch.
Answer and Explanation:
25. (d): Pyrenoids are the centres for the formation of starch. There are present in chloroplast and are proteinaceous in nature covered by a starch plate. They synthesize and store starch in them.
26. Pinus differs from mango in having
(a) tree habit
(b) green leaves
(c) ovules not enclosed in ovary
(d) wood.
Answer and Explanation:
26. (c): Pinus is a gymnospermic plant which hives a well developed conducting tissue system but seeds are naked. Whereas mango is a angiospermic plants in which seed are enclosed in the ovary and fruit is present.
27. Which one is the most advanced from evolutionary viewpoint?
(a) Selaginella
(b) Funaria
(c) Chlamydomonas
(d) Pinus.
Answer and Explanation:
27. (d): Pinus is more advanced from the evolutionary point of view. It is a gymnosperm (of phanerogams) having well developed vascular conducting system and bears seeds. While others Selaginella, Funaria and Chlamydomonas do not bear seeds.
28. In bryophytes
(a) both generations are independent
(b) gametophytes are dependent upon sporophytes
(c) sporophytes complete their life cycle
(d) sporophytes are dependent upon gametophytes.
Answer and Explanation:
28. (d): In Bryophytes the main body is gametophytic (n) which is independent and may be thallose (no differentiation in root, stem and leaves). It bears sex organs and after fertilization the sporophytic phase starts. The sporophyte is organically attached to the gametophytic plant and is nutritionally dependent on the gametophyte. It may be wholly or partially dependent on the gametophyte.
29. In Pinus, the wings of the seed develops from
(a) ovuliferous scale
(b) integument
(c) nucellus
(d) bract.
Answer and Explanation:
29. (a): Mature ovule with embryo constitutes seed. The seed is covered with hard seed coat. The outer layer of the seed coat is testa (from middle stony layer). Testa encloses a brown, thin membranous tegmen (from inner fleshy layer). The tegmen surrounds fleshy endosperm. Inside endosperm is present the embryo. At maturity of seed, a thin layer of ovuliferous scale fuses with testa to form a wing (i.e., seeds are winged) which helps in the dispersal of seed.
30. In chlorophyceae, the mode of sexual reproduction is
(a) isogamy
(b) anisogamy
(c) oogamy
(d) all of these.
Answer and Explanation:
30. (d): The class chlorophyceae is characterised by the members possessing grass-green chromatophores. The other distinguishing features of the class are the presence of starch-as reserve food material, pyrenoids – commonly surrounded by starch sheaths, motile cells bearing anterior flagella of equal length, etc.
In chlorophyceae, three types of sexual reproduction take place namely isogamy, anisogamy and oogamy. Isogamous type: Here the fusing gametes are morphologically similar but physiologically distinct e.g., Chlamydomonas debaryanum and Ulothrix. Anisogamous type: Fusion takes place between morphologically and physiologically distinct gametes (anisogametes). Chlamydomonas braunii and Pandorina. Oogamous type: Most advanced type in which fusion of small biciliate or multiciliate, active male gamete with large, passive female gamete, Oedogonium, Chlamydomonas coccifera.
