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.
Correct Answer :
A. power of adaptability in diverse habitat.
Angiosperms are highly evolved and well adapted land plants. They have both vessels and tracheids in xylem for better conduction of water. Roots are modified into tap roots, adventitious roots, pneumatophores etc. to suit the desired climate. Sex organs are highly developed, sporophylls are organized into flowers and the flowers are highly coloured or attract pollinators at different times and places. Insect pollination is more prevalent because it is more efficient and leads to less wastage of pollen grains as compared to wind pollination. So the flowers are made attractive to attract a variety of insects. Seeds are more protected as they are enclosed inside a fruit. All these adaptations have made angiosperms more adaptive in diverse habitats.
Related Questions
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.
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
Mosses do not have true leaves because their leaf-like structures lack
starch in their chloroplast.
vascular tissues.
chlorophyll.
cellulose in their cell walls.
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.
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.
Match column-I with column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| A. Smallest flowing plant | I. Eucalyptus |
| B. Male sex organ in | II. Wolffia flowering plant |
| C. Female sex organ | III. Stamen in flowering plant |
| D. Tallest tree | IV. Pistil |
A I; B II; C III; D IV
A IV; B III; C II; D I
A II; B III; C IV; D I
A II; B IV; C III; D I
Laminaria (Kelp) and Fucus (Rock weed) are examples of
green algae
brown algae
red algae
golden brown algae
Classification of plants proposed by Carolus Linnaeus was artificial because it was based on
only a few morphological characters.
evolutionary tendencies which are diverse.
anatomical characters which are adaptive in nature.
physiological traits alongwith morphological characters.
Match column-I with column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| A. Amphibian of the | I. Sphagnum plant kingdom |
| B. Specialized structures | II. Angiosperms in liverworts for asexual reproduction |
| C. Monocotyledons and | III. Bryophytes dicotyledons |
| D. A plant which has | IV. Gemmae capacity to holding water |
A III; B IV; C I; D II
A III; B IV; C II; D I
A IV; B III; C II; D I
A III; B II; C IV; D I
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
If the cells of root in wheat plant have 42 chromosomes, then the no. of chromosome in the cell of pollen grain is
14
21
28
42
Statement 1: Members of phaeophyceae vary in colour from olive green to various shades of brown.
Statement 2: Phaeophyceae possess chlorophyll a, c, carotenoids and xanthophylls.
Both statements -1 and statement - 2 are true and statement - 2 is the correct explanation of statement - 1.
Both statements -1 and statement - 2 are true but statement - 2 is not the correct explanation of statement - 1.
Statement -1 is true and statement - 2 is false.
Statement -1 is false and statement - 2 is true.
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
The unique feature of bryophytes compared to other plant groups is that
they produce spores.
they lack vascular tissues.
they lack roots.
their sporophyte is attached to the gametophyte.
Why rhodophyta exhibit a red colour ?
Since most rhodophyta grow at great depths, the chlorophyll can only absorb light in the red area of the spectrum.
The wavelengths of light that are absorbed by chlorophyll are passed to phycoerythrin (a red pigment).
Red pigment of rhodophyta absorbs all the light waves.
The light reaching the greatest depth in water is in the blue-green region of the spectrum, is absorbed by phycoerythrin.
The following statements are associated with one class of algae. Identify the class of algae.
(i) One or more storage bodies called pyrenoids located in the chloroplasts are present in the members of this class.
(ii) They have a rigid cell wall made of an inner layer of cellulose and an outer layer of pectose.
(iii) Asexual reproduction is by flagellated zoospores produced in zoosporangia.
(iv) Chlamydomonas, Volvox, Ulothrix, Spirogyra and Chara are commonly found members of this class.
Chlorophyceae
Rhodophyceae
Phaeophyceae
None of these
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
Which of the following group of plant is being described by the given statements ?
(i) They are plants in which the ovules are not enclosed by any ovary wall and remain exposed before and after fertilization.
(ii) The giant red wood tree Sequoia is one of the tallest tree species of the group.
(iii) The roots are generally tap roots.
(iv) They are heterosporous and they produce haploid microspores and megaspores.
Algae
Bryophytes
Gymnosperms
Pteridophytes
Match column-I with column-II and choose the correct option.
| Column-I | Column-II |
|---|---|
| A. Phaeophyceae | I. Have an elaborate mechanism of spore dispersal |
| B. Rhodophyceae | II. first terrestrial plant with vascular tissue-phloem and xylem |
| C. Mosses | III. Asexual reproduction by biflagellate zoosposes |
| D. Pteridophytes | IV. Polysiphonia, Porphyra, Gracilaria |
A III; B IV; C I; D II
A IV; B III; C I; D II
A IV; B III; C II; D I
A IV; B I; C III; D II
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.
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)
Mosses are of great ecological importance because of
its contribution to prevent soil erosion.
its contribution in ecological succession.
its capability to remove CO from the atmosphere.
both (a) and (b)
Which one of the following is a correct statement?
Pteridophyte gametophyte has a protonemal and leafy stage.
In gymnosperms, female gametophyte is free-living.
Antheridiophores and archegoniophores are present in pteridophytes.
Origin of seed habit can be traced in pteridophytes.
Moss peat is used as a packing material for sending flowers and live plants to distant places because
it reduces transpiration.
it serves as a disinfectant.
it is easily available.
it is hygroscopic.
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
Which of the following class of algae is mostly found in salt water ?
Phaeophyceae
Rhodophyceae
Chlorophyceae
Both (a) and (b)
What is the similarity between gymnosperms and angiosperms?
Phloem of both have companian cells.
Endosperm is formed before fertilization in both.
Origin of ovule and seed is similar in both.
Both have leaves, stem and roots.
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
Fruits are not formed in gymnosperms because of
absence of pollination.
absence of seed.
absence of fertilization.
absence of ovary.
Phylogenetic classification system is based on the
morphological characters of various organisms.
anatomical characters of various organisms.
physiological characters of various organisms.
evolutionary relationships between the various organisms.