31 Years NEET Previous Year Questions: Plant Kingdom - 2 - NEET MCQ

Cyanobacteria, e.g., Nostoc, grow in such abundance as to form water blooms. Sargassum belongs to brown algae which possess chl a, c, carotenoids, xanthophyll and a characteristic brown pigment, fucoxanthin. Commonly known forms of basidiomycetes are mushrooms, bracket fungi or puffballs. In Spirogyra gametes are non-flagellated (non-motile) but similar in size. They show amoeboid movements.

Topic in NCERT: Sexual reproduction in algae

Line in NCERT: "sexual reproduction shows considerable variation in the type and formation of sex cells and it may be isogamous, anisogamous or oogamous."

The female sex organ archegonium is formed in bryophytes (Funaria), pteridophytes (Dryopteris) and gymnosperms (Ginkgo).

Topic in NCERT: Gametophyte

Line in NCERT: "the gametophytes bear male and female sex organs called antheridia and archegonia, respectively."

The plant body of a liverwort is haploid (n), gametophytic, small, dorsoventrally flattened, thallose, dichotomously branched fixed by unicellular and unbranched rhizoids, e.g., Marchantia.

Topic in NCERT: Bryophytes

Line in NCERT: "the plant body of liverworts is thalloid and dorsiventral whereas mosses have upright, slender axes bearing spirally arranged leaves."

d and e are incorrect statements.
• The sporophyte in liverworts is less elaborate than that in mosses.
• Pinus is monoecious, Marchantia is dioecious.

 In Spirogyra, sexual reproduction occurs through conjugation. Gametes are nonflagellated morphologically similar. But physiologically different (isogamy with physiological anisogamy). Volvox and fucus are examples of oogamous and Chlamydomonas contains isogamous flagellated gametes .

Topic in NCERT: Algae

Line in NCERT: "such reproduction is called isogamous."

In Cycas specialised root called coralloid roots are associated with N₂ – fixing cyanobacteria either Nostoc or Anabaena. Coralloid roots lie near the soil surface. They are irregular and often dichotomously branched. Root hair  and root cap are absent in these roots. 

Topic in NCERT: Gymnosperms

Line in NCERT: "the roots in some genera have fungal association in the form of mycorrhiza (pinus), while in some others (cycas) small specialised roots called coralloid roots are associated with n2- fixing cyanobacteria."

Salvinia is heterosporoues water fern. the microsporangia and megasporangia are borne with a special reproductive structure called sporocarps. These are borne termonaly on clusters on a segment of submerged leaves. Sporocarps are strictly monosporangiates i.e they either bear microsporangia or megasporangia.

Viroids  are single stranede RNA molecules. The female reproductive organ is archegonia in gymnosperms.

Topic in NCERT: Pteridophytes

Line in NCERT: "genera like selaginella and salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous."

Statement (A) and (B) are correct Riccia is liverwort in which simplest sporophyte consists of capsule only while Polytrichum is moss in which sporophyte consists of foot seta &     capsule. Volvox is a fresh water green colonial alga. Reproduction is both sexual and asexual. Sexual reproduction is oogamous. Slime molds are consumer decomposer protists. They possess characters of plants (cellulosic cell wall), animals (phagotrophic nutrition) and fungi (spores)

Topic in NCERT: Gymnosperms

Line in NCERT: "the female gametophytes in these plants are retained on the parent sporophytes for variable periods."

Multicellular fungi, filamentous algae and protonema of mosses all show multiplication by fragmentation. 

Topic in NCERT: Reproduction in algae

Line in NCERT: "algae usually reproduce vegetatively by fragmentation, asexually by formation of different types of spores and sexually by formation of gametes."

(1) Gametophyte of bryophytes bears protonemal & leafy stage. (2) In gymnosperm female gametophyte is not free living. (3) They are present in Marchantia or which is a bryophyte. (4) Origin of seed habit started in pteridophyte Selaginaella.

Topic in NCERT: Gymnosperms

Line in NCERT: "the development of the zygotes into young embryos take place within the female gametophytes. this event is a precursor to the seed habit considered an important step in evolution."

Cycas (a gymnosperm) and Adiantum known as Maiden hair fern is a pteridophyte resemble each other in having motile sperm. Seeds, cambium are common in gymno-sperms and absent in pteridophytes. True vessels are absent in both  pteridophytes and gymnospems.

Topic in NCERT: Gymnosperms

Line in NCERT: "the gymnosperms are heterosporous; they produce haploid microspores and megaspores."

Sphagnum is a bryophyte in which male and female gametophytes are independent and free living. In pinus (a gymnosperm), mustard and castor (angiosperms), the main plant body is sporophytic. Gametophyte is highly reduced and is completely dependent on sporophyte.

Topic in NCERT: Bryophytes

Line in NCERT: "bryophytes are also called amphibians of the plant kingdom because these plants can live in soil but are dependent on water for sexual reproduction."

Pinus plant is monoecious i.e. both male and female cone are present in same plant but on different branches. Pinus, with over 100 species, is the largest genus of conifers and the most widespread genus of trees in the Northern Hemisphere. Pinus are also extensively planted in temperate regions of the Southern Hemisphere. Pines have a relatively rich fossil record.

Topic in NCERT: Gymnosperms

Line in NCERT: "the male or female cones or strobili may be borne on the same tree (pinus)."

Salvinia is an aquatic fern with both annual and perennial species- b is heterosporous i.e. with two types of spores, microspores and megaspores

Topic in NCERT: Pteridophytes

Line in NCERT: "genera like selaginella and salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous."

 Male and female gametophytes of Cedrus do not have free living independent existence. Cedrus belongs to conifer. 

Topic in NCERT: Gymnosperms

Line in NCERT: "unlike bryophytes and pteridophytes, in gymnosperms the male and the female gametophytes do not have an independent free-living existence."