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Right ANSWER is (b) Diplontic

Explanation: Rose plant belongs to the CATEGORY of Angiosperms.All angiosperms and gymnosperms exhibit diplontic LIFE cycle i.e. SPOROPHYTE is the dominant PHASE and has independent existence.

Correct option is (c) MEGASPORANGIUM tissue is soft and non-woody

The explanation: The reduced male gametophyte is termed as pollen GRAINS. Pollen grains may be monosaccate, disaccate, trisaccate or non-saccate. Megasporangium tissue is hardy and woody in NATURE. After MITOSIS, a megaspore forms female gametophyte with two or three archegonia that undergoes fertilization.

Correct answer is (b) False

Easy explanation: Male and female GAMETES need not be present in the same LEAFY liverworts in order to facilitate reproduction. In case of mosses, male and female reproductive organs GROW on same THALLUS as antheridial branch and ARCHEGONIAL branch.

Right CHOICE is (a) Gametes are produced in SEX organs CALLED gametophytes

The best explanation: Gametes are produced in sex organs called gametophytes. MALE gametes are transported to female gametes through WATER. Male and female gametes further fuse to form a zygotic structure that develops into an embryo. This embryo further develops to form a haploidic structure called sporophytes that bear spores.

The correct answer is (a) True

For explanation: BRYOPHYTES are thalloid like structures and have virtual ROOTS, stems and leaves. ALTHOUGH their distinction is better than that of Thallophytes, they are still thalloid like structures.

Correct choice is (b) HAPLONTIC

Easy explanation: Most of the algae are haplontic whereas few others are diplontic. POLYSIPHONIA and ECTOCARPUS and kelps are few such algae that exhibit haplontic life CYCLE i.e. Gametophyte acts as the dominant phase in case of Polysiphonia.

Right option is (d) ECTOCARPUS exhibits haplo-diplontic LIFE cycle

Easy explanation: In this life cycle both the sporophytic and GAMETOPHYTIC phase are multi-cellular and have independent existence. In this life cycle, the dominant phases differ. This kind of life cycle is exhibited by Pteridophytes and BRYOPHYTES. Ectocarpus exhibits haplo-diplontic life cycle.

The correct answer is (a) HAPLONTIC

Explanation: CHLAMYDOMANAS exhibits haplontic life cycle i.e. GAMETOPHYTE are the dominant phase in this life cycle. In this life cycle, there is no independent existence for SPOROPHYTE. SPORES produced are haploid and divide mitotically to form Gametophyte.

Correct option is (a) Diplontic

The best EXPLANATION: GENERALLY, most of the ALGAE are haplontic whereas few OTHERS are diplontic. Fucus is one such alagae that exhibits diplontic behavior i.e. Sporophyte is the dominant phase in case of fucus.

The correct option is (a) Because they grow in water during summer and on land in winter

The EXPLANATION is: BRYOPHYTES are called as PLANT AMPHIBIANS. Although they can manage to grow on land in normal conditions, water is essential for them to transmit male gametes to female gamete in order to facilitate reproduction.

Correct option is (a) Fragmentation

To ELABORATE: In fragmentation, a parent ORGANISM BREAKS into a fragment and each fragment GIVES a new individual. Spirogyra USES fragmentation to reproduction.

Correct choice is (a) True

Easy explanation: Gametophytes in plants that exhibit diplontic life cycle may be heterotrophic, autotrophic or saprophytic. For EXAMPLE: in angiosperms, few FLOWERS can PERFORM PHOTOSYNTHESIS while few others are carnivorous like DROSERA and nepenthes and few others are saprophytic like Broomrape.

Correct CHOICE is (c) Gemmae are sexual PROPAGATIVE organs in Liverworts that contain gemmae which further gives rise to a new individual

The best I can explain: In mosses, spores germinate to form protonema, a green creepy structure that further develops into leaf like thallus. Rhizoids HOLD mosses to ground and prevent SOIL erosion. Gemmae are asexual propagative organs in Liverworts that contain gemmae which further gives rise to a new individual. Water is EXTREMELY important for carrying male gamete towards female gamete in order to facilitate sexual reproduction of bryophytes.

Correct choice is (b) False

To ELABORATE: Gymnosperms are heterosporous i.e. they have different SPORES. The LARGER ONES are called macro or mega spores that give rise to a female gametophyte. The smaller ones are called microspores and they germinate to FORM male gametophyte.

The correct option is (c) MOSES CONTAIN lobes in their LEAVES whereas leafy liverworts don’t

Explanation: Most of the leafy liverworts resemble mosses in their structure. Leafy liverworts contain oil BODIES that are absent in mosses. Leafy liverworts contain lobes in their leaves whereas don’t mosses. In mosses, leaves are spirally arranged but in leafy liverworts leaves grow in two or three ROWS.

Right option is (b) False

The EXPLANATION is: Both HAPLOID and diploid cells UNDERGO MITOSIS to form plant bodies. This results in the formation of either haploid or diploid plant bodies. The haploid plant body is GAMETOPHYTE and the diploid one is a Sporophyte.

Correct ANSWER is (a) Rhizoids

Best explanation: BRYOPHYTES are erect with hair like structures CALLED rhizoids. Rhizoids anchor bryophytes to the soil and help in transfer of nutrients from soil to the thallus. They are also called virtual roots of bryophytes.

Correct answer is (c) Haploid gametophyte

Easiest EXPLANATION: Haploid gametophyte is the DOMINANT phase in the life cycle of liverworts. Diploid SPOROPHYTE, diploid ZYGOTE and diploid SPORES are short living intermediary structures that finally result in gametophyte.

Right answer is (C) Ulothrea is a unicellular autotrophic algal

To elaborate: Ulothrea are MULTICELLULAR autotrophic algae. Chlamydomanas is an example of unicellular algae. Chlamydomanas have flagella to PROMOTE their movement. Spirogyra attains its name because of spiral LIKE ARRANGEMENT of chloroplasts.

The CORRECT answer is (b) Leaves of Gymnosperms can be either simple/ compound

For explanation I would SAY: Some Gymnosperms have algal ASSOCIATION in their roots and it is termed as mycorrhiza. Leaves of Gymnosperms can be either simple/ compound. Gymnosperms have either branched/unbranched stems. The roots in Pinus exist in the form of mycorrhiza.

Correct choice is (a) True

Easiest explanation: After fertilization, the zygote DEVELOPS into an embryo and the megasporangium tissue PROVIDES NUTRITION for the development of the embryo. APART from providing nutrition to the embryo, megasporangium tissue plays a vital role in the development of the female gametophyte.

Correct option is (d) Mycorrhiza

The best EXPLANATION: In cycas, the TYPE of root present is called coralloid root. Coralloid ROOTS are short and irregularly branched. They EXIST in SYMBIOTIC association with cyanobacteria that help them in fixation of Nitrogen.

Correct option is (c) It is edible and are used in salads

To EXPLAIN: Chladophora is a FILAMENTOUS branched algal. Chladophora is also called river weed in some areas. It is edible. There are many different varieties of chladophora that are DIFFICULT to be classified. Ulva are also called as SEA LETTUCE since they are used in salads.

Right choice is (d) CYTOTAXONOMY involves only external characteristics

Easiest EXPLANATION: Cytotaxonomy is based on the chromosomes present in the organism. Cytotaxonomy involves both internal and external characteristics of plant. Cytotaxonomy involves characteristics like number of chromosomes, division of CELL and POSITION centromere. Chemotaxonomy is based on the CHEMICAL composition of plants.

The CORRECT option is (b) Sporophytes are free-living

The explanation is: Gametophytes are the DOMINANT phase in this life cycle. Sporophytes don’t have free living EXISTENCE. SPORES are haploid in nature and form GAMETOPHYTE by mitotic division. Zygote acts as Sporophyte that forms spores.

The correct choice is (C) Sporangia

Best explanation: Sporophytes BEAR sporangia in LEAF LIKE structures called sporophylls. Sporangia further ruptures to form spores that germinate into a gametophyte CONTAINING archegonium and antheridium.

Correct ANSWER is (a) True

Explanation: Megaspores or Macrospores form FEMALE gametophyte after germination. Microspores GERMINATE to form male gametophyte. Male and female gametophyte, also called as PROTHALLUS, FUSE to form a zygote.

The correct answer is (b) MOSSES

To elaborate: Sphagnum belongs to BRYOPHYTES and to the sub-classification of mosses. Sphagnum has a very GOOD COMMERCIAL importance and is used in the packing of cookery and glass materials.

The correct answer is (b) Chlorella and Spirullina are multi-cellular algae that are rich proteins and are used as food SUPPLEMENTS for space travelers

The EXPLANATION is: Algae help in increasing oxygen levels in the environment. Chlorella and Spirullina are multi-cellular algae that are rich proteins and are used as food supplements for space travelers. CHLOROPHYCEAE comprise algae that CONTAIN chlorophyll a and chlorophyll b. Chlorophyceae store food as proteins, starch or as oil droplets.

Correct choice is (a) True

To explain: Thallophyta FOLLOW cryptogamae. The word “crypto” means SECRET and “gamae” means reproduction i.e. Thallophyta reproduces in a hidden manner using spores without formation of SEEDS or FLOWERS.

Correct option is (b) Microspores further undergo REDUCTION division to form microgametophyte

The best EXPLANATION: Microsporangia contain microsporocytes that undergo meiosis to form microspores. Microspores further undergo reduction division to form microgametophyte. Microgametophyte is also called as Pollen GRAIN. Wind, water and insects act as dispersal agents for POLLINATION.

Right answer is (b) Lycopsida

Easy EXPLANATION: Equisetum belongs to Pteridophytes under the sub-classification of Sphenopsida.Equisetum is also CALLED as horse’s tail plant because Equus in LATIN MEANS horse whereas SETA means “bristle”. Equisetum is known to be used as medicine traditionally.

The correct option is (c) In Spirogyra, DIPLOID Sporophyte is the dominant PHASE

To explain I would SAY: Haploid gametophyte is the dominant phase in bryophytes and in volvox. ALSO in Spirogyra, the diploid Sporophyte is the dominant phase. In PAPAYA, haploid gametophyte is the dominant phase.

Correct option is (d) Bryophytes don’t absorb WATER and are used to pack food materials

Easy explanation: Bryophytes hold SOIL firmly and THEREFORE prevent soil erosion. Bryophytes decompose barren rocks and MAKE soil fertile. Bryophytes are used as PACKING materials and as good fuel. Bryophytes are good absorbers of water and can’t be used for packing of food materials.

Correct answer is (b) Sporophyte is also called Pro-thallus

The BEST I can explain: Gametophyte is small and multi-cellular PHOTOSYNTHETIC thallus. Sporophyte is also called Pro-thallus. In mosses, gametophyte is the DOMINANT PHASE. Equisetum and Selaginella have a distinct cone like structure called strobili.

The correct option is (C) Pteridophytes grow in dry and cold places like mountains

For EXPLANATION: Pteridophytes follow cryptogamae i.e. reproduce spores. The main plant BODY in Pteridophytes is Sporophyte. Pteridophytes grow in a damp shady area and sometimes even in SANDY soils. Pteridophytes have specialized vascular tissues.

The CORRECT OPTION is (b) False

The BEST I can explain: Haploidic gametophyte is the predominant phase in the life cycle of mosses. Protonema, Sporophyte, Spores and ZYGOTE are intermediary STRUCTURES in the life cycle of mosses.

Correct option is (b) ZYGOTE UNDERGOES REDUCTION division to form a structure called sporophyte

To explain I would say: Zygote is formed by fusion of male and female gametes and is diploid in nature. Zygote doesn’t undergo reduction division immediately after fusion. They instead form a structure called as sporophyte. Sporophyte undergoes meiosis to produce SPORES. Spores germinate to form new thallus.

Right choice is (d) They are immobile DUE to absence of flagellum

The explanation is: Volvox GROWS in colonies. The structures that connect them are called cytoplasmic bridges. Daughter colonies of volvox grow inside the PARENT colony. They CONTAIN flagellum that FACILITATES their movement.

Correct choice is (a) True

The EXPLANATION: Rhodophyceae are also CALLED as red algae because of the presence of a red pigment called r-phycoerythrin. They are MOSTLY found in marine WATER and float on the surface of the water.

The correct OPTION is (a) In natural classification, only internal structures of the plants are CONSIDERED

For explanation: Natural classification overcomes the limitations of the plants. Both internal and external structures are considered to be the basis of natural classification. Natural classification CONSIDERS REPRODUCTIVE mode, embryotic structure and ultra structure of plants. It ESTABLISHES close relationship between plants.

The correct choice is (B) False

Explanation: Both haploid and diploid cells UNDERGO MITOSIS to FORM plant bodies. This results in the FORMATION of either haploid or diploid plant bodies. The haploid plant body is gametophyte and the diploid one is a Sporophyte.

Correct option is (c) Sporophyte

For explanation: Sporophyte is dominant PHASE in the LIFE cycle of a Pteridophyte whereas Gametophyte, PROTHALLUS and Zygote are intermediary stages in the life cycle of a Pteridophyte.