Read the following statements and answer the question.
(i) Sporophytic generation is represented only by the one-celled zygote.
(ii) Meiosis in the zygote results in the formation of haploid spores.
(iii) The dominant, photosynthetic phase in such plants is free-living gametophyte.
(iv) Many algae such as Volvox, Spirogyra and some species of Chlamydomonas represent this pattern.
Which of the following pattern of life cycle of plant is described by the above statements ?
Haplontic
Diplontic
Haplo-diplontic
None of these
Correct Answer :
A. Haplontic
Haplontic life cycle is a simplest and most primitive type of life-cycle found in all chlorophyceae. In haplontic pattern of life cycle, the somatic phase (plant) is haploid (gametophyte) while the diploid phase (sporophyte) is represented by zygote. During germination the zygote (2n) divides meiotically producing haploid (n) zoospores, which develop into individual plant. Here the unicellular or filamentous gametophyte (n) alternates with one-celled zygote or sporophyte (2n).
Related Questions
Which of the following statement(s) is/are correct?
(i) Green algae are the members of chlorophyceae.
(ii) Brown algae are found primarily in marine habitates
(iii) Some red algae are found in fresh water, mostly occur in salt water, some are in brackish water.
(iv) The food in red algae is stosed as floridean starch.
(v) Red alga may occur in both well-lighted regions close to water-surface and also at great depths in oceans where light penetration is little.
(i) and (v) only
(ii), (iii) and (iv) only
All of the above
None of the above
In angiosperms, a mature male gametophyte is derived from a pollen mother cell by
three mitotic divisions.
one meiotic and two mitotic divisions.
two meiotic divisions.
a single meiotic division.
Which of the following statement(s) is/are correct about angiosperms ?
(i) In angiosperms or flowering plants, the pollen grains and ovules are developed in specialised structure called flowers.
(ii) They are divided into two classes : the dicotyledons and the monocotyledons.
(iii) The male sex organ in a flower is the pistil or the carpel.
(iv) The female sex organ is the stamen.
Only (i)
Both (i) and (ii)
Both (ii) and (iv)
All of these
Cycas and Adiantum resemble each other in having
seeds
motile sperms
cambium
vessels
Which of the following statement is incorrect ?
Double fertilization is unique to gymnosperms and monocotyledons.
Sequoia, a gymnosperm, is one of the tallest tree species.
Phaeophyceae members possess chlorophyll a, c, carotenoids and xanthophylls.
Moss is a gametophyte which consists of two stages namely, protonemal stage and leafy stage.
Place the following groups of plants in order, beginning with those that first appeared on the earth and progressing toward those that appeared most recently in time.
Gymnosperms, angiosperms, ferns, moss, algae
Algae, moss, ferns, gymnosperms, angiosperms
Moss, algae, ferns, angiosperms, gymnosperms
Algae, ferns, angiosperms, gymnosperms, moss
Which of the following statement(s) is/are correct about gemmae ?
(i) These are specialised structures by which asexual reproduction take place in liverworts.
(ii) They are green, multicellular and asexual buds.
(iii) They develop in small receptacles called gemma cups.
(iv) They detach from parent body and germinate to form new individuals.
(i) and (ii)
(ii) and (iii)
(i), (ii) and (iii)
All of these
Deep in the tropical rain forest, a botanist discovered an unusual plant with vascular tissues, stomata, a cuticle, flagellated sperm, conelike reproductive structures bearing seeds, and an alternation-of-generations life cycle. He was very excited about this discovery because it would be rather unusual for a plant to have both
a cuticle and flagellated sperm.
vascular tissues and alternation of generations.
seeds and flagellated sperm.
alternation of generations and seeds.
Bryophytes are different from fungi in having
land habit.
sterile jacket layers.
multiflagellate gametes.
gametophytic plant body.
Which of the following statement(s) is/are correct ?
In angiosperms, each embryo sac has a three-celled egg apparatus one egg cell and two synergids, three antipodal cells and two polar nuclei.
All seed bearing plants i.e., gymnosperms and angiosperms follow dipontic life patterns of plants.
In gymosperms, roots in some genera have fungal association in the form of mycorrhiza (Pinus) while in some others (Cycas) small specialized roots called coralloid are associated with N2 fixing cyanobacteria.
All of the above
Match the column I with column II and choose the option which shows its correct combination.
| Column-I | Column-II |
|---|---|
| (Pattern of life cycle in plant) | (Examples) |
| A. Haplontic | I. Bryophytes, Pteridophytes, life cycle Ectocarpus, Polysiphonia, Kelps |
| B. Diplontic | II. Seed bearing plants life cycle (Gymnosperm and Angiosperm), Fucus |
| C. Haplo-diplontic | III. Many algae (Volvox, life cycle Spirogyra) and some species of Chlamydomonas |
A III; B II; C I
A I; B II; C III
A II; B I; C III
A III; B I; C II
If you are asked to classify the various algae into distinct groups then which of the following characters you should choose for the classification ?
Nature of habitat
Structural organization of thallus
Chemical composition of the cell wall
Types of pigments present in the cell.
Which of the following statements are incorrect?
Pyrenoids contain protein besides starch.
Sexual reproduction may be isogamous, oogamous and anisogamous in green and brown algae.
Some of the members of algae also occur in association with fungi (lichen) and animals (eg, on sloth bear).
The leaves in pteridophytes are well adapted to withstand extremes of temperature, humidity and wind.
A research student collected certain alga and found that its cells contained both chlorophyll a and chlorophyll d as well as phycoerythrin on the basis of his observation the students conclude that the alga belongs to
rhodophyceae
bacillariophyceae
chlorophyceae
phaeophyceae
Protonema and leafy stage are the predominant stage of the life cycle of
moss
dicots
liverwort
gymnosperm
Which of the following statement(s) is/are correct ?
(i) Agar, one of commercial products obtained from Laminaria and Sargassum are used to grow microbes and in preparations of ice-creams and jellies.
(ii) In phaeophyceae, major pigments are chl a, d and phycoerythrin.
(iii) Pteridophytes classified into four classes : Psilopsida, Lycopsida, Sphenopsida and Pteropsida.
(iv) Gemmae are green, multicellular, asexual buds, which develop in small receptacles called gemma cups located on the thalli.
Both (i) and (ii)
Both (ii) and (iv)
Both (iii) and (iv)
All of these
You are given an unknown plant to study in the laboratory. You find that it has chlorophyll, no xylem. Its multicellullar sex organs are enclosed in a layer of jacket cells. Its gametophyte stage is free living. The plant probabily belongs to
chlorophyceae
bryophyte
pteridophyte
gymnosperm
Fern plant is a
haploid gametophyte
diploid gametophyte
diploid sporophyte
haploid sporophyte
Which of the following statement(s) is incorrect about mosses ?
The predominant stage of its life cycle is the gametophyte which consists of two stages protonema and leafy stages.
Leafy stage are attached to the soil through unicellular and branched rhizoids.
Sex organs-antheridia and archegonia are produced at the apex of the leafy shoots.
All of the above
Fruits are not formed in gymnosperms because of
absence of pollination.
absence of seed.
absence of fertilization.
absence of ovary.
Which of the following statements with respect to algae are correct.
(i) Fusion between one large, non-motile female gamete and a smaller, motile male gamete is termed as oogamous.
(ii) Fusion of two gametes dissimilar in size is termed as oogamous.
(iii) Fusion of two gametes similar in size is called anisogamous.
(iv) In chlorophyceae, the major pigments are chlorophyll a and b , and the food is stored as starch.
(v) In rhodophyceae, the major pigments are chlorophyll a and d , and the food is stored as mannitol.
(i) and (v)
(iii) and (v)
(i) and (ii)
(i) and (iv)
What is the number and position of insertions of flagella in rhodopyceae class of algae ?
2 - 8, equal, apical
2, unequal, lateral
2 - 6, equal, lateral
Absent
Which one of the following term is correctly matched with their definition in Pinus ?
Monoecious Male (microsporangiate) and female (megasporangiate) cones are produced on same plant.
Monoecious Male and female sporophylls borne on same strobilus.
Dioecious Male and female cones are produced on different plants.
Monoecious Micro and megasporocarp develop on same plant.
Consider the following statements regarding gymnosperms and choose the correct option.
(i) In gymnosperms, the male and female gametophytes have an independent existence.
(ii) The multicellular female gametophyte is retained within the megasporangium.
(iii) The gymnosperms are heterosporous. Of these statements
(i) and (ii) are correct but (iii) is incorrect
(i) and (iii) are correct but (ii) is incorrect
(ii) and (iii) are incorrect but (i) is correct
(ii) and (iii) are correct but (i) is incorrect
Which of the following class of algae is rarely found in fresh water ?
Chlorophyceae
Phaeophyceae
Rhodophyceae
Both (a) and (b)
Select the correct match of the feature present in column I with its respective terms given in column II.
| Column-I | Column-II |
|---|---|
| A. Presence of tap roots | (i) Bryophyte and coralloid roots |
| B. The synergids and | (ii) Pteridophytes antipodal cells degenerates after fertilization |
| C. The food is stored as | (iii) Red algae floridean starch which is very similar to amylopectin and glycogen in structure |
| D. Presence of sporophyte | (iv) Angiosperms which is not free living but attached to the photosynthetic gametophytes and derives nourishment from it |
| E. Members of this group | (v) Gymnosperms are used for medicinal purposes, as soil binders and frequently grown as ornamentals |
A-i B-ii C-iii D-iv E-v
A-iii B-v C-ii D-iv E-i
A-iii B-i C-v D-ii E-iv
A-v B-iv C-iii D-i E-ii
Which of the following pteridophytes belong to class pteropsida?
Equisetum and Psilotum
Lycopodium and Adiantum
Selaginella and Pteris
Pteris and Adiantum
Which of the following groups of plants play an important role in plant succession on bare rocks/soil ?
Algae
Bryophytes
Pteridophytes
Gymnosperms
Angiosperms have dominated the land flora primarily because of their
power of adaptability in diverse habitat.
property of producing large number of seeds.
nature of self pollination.
domestication of man.
Read the following statements and choose the correct option.
(i) In rhodophyceae, food is stored in the form of mannitol and laminarin.
(ii) The ovules of gymnosperms are not enclosed by ovary wall.
(iii) Salvinia is heterosporous.
(iv) In the diplontic life-cycle, the free living gametophyte represents the dominant phase.
(ii) and (iii) are correct but (i) and (iv) are incorrect.
(ii) and (iv) are correct but (i) and (iii) are incorrect.
(iii) and (iv) are correct but (i) and (ii) are incorrect.
(i) and (ii) are correct but (iii) and (iv) are incorrect.