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.
Correct Answer :
B. The wavelengths of light that are absorbed by chlorophyll are passed to phycoerythrin (a red pigment).
Rhodophyta are commonly called as red algae because of the predominance of the red pigment (r phycoerythrin) in their body. They occur in both well lighted regions close to the surface of water and also at great depths in ocean where relatively little light penetrates. They exhibit a red colour because the wavelengths of light that are absorbed by chlorophyll are passed to phycoerythrin.
Related Questions
Flagellate isogametes and anisogametes are found in
Spirogyra
Fucus
Volvox
Chlamydomonas
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
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 statements (i) - (v) are correct ?
(i) In Equisetum, the female gametophyte is retained on the parent sporophyte.
(ii) In Ginkgo, male gametophyte is not independent.
(iii) The sporophyte in Riccia is more developed than that in Polytrichum.
(iv) Sexual reproduction in Volvox is isogamous.
Two
Three
Four
One
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)
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
Cytological information like chromosome number, structure, behaviour are related with
numerical taxonomy
cytotaxonomy
chemotaxonomy
all of the above
Laminaria (Kelp) and Fucus (Rock weed) are examples of
green algae
brown algae
red algae
golden brown algae
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
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. Agar | I. Single cell protein, used as food supplements by space travellers |
| B. Algin | II. Red algae |
| C. Carrageen | III. Brown algae |
| D. Chlorella | IV. Gelidium, Gracilaria Spirullina |
A I; B II; C III; D IV
A IV; B III; C II; D I
A II; B I; C III; D IV
A III; B II; C I; D IV
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.
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
Which of the following statements with respect to gymnosperms and angiosperms is/are correct?
(i) The process of double fertilization is present in gymnosperms.
(ii) Angiosperms range in size from microscopic Wolffia to tall trees of Sequoia.
(iii) In gymnosperms, the seeds are not covered.
(iv) In gymnosperms, the male and female gametophytes have an independent free living existence. Of the above statements
(i) and (ii)
(iii) only
(ii) and (iii)
(iii) and (iv)
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.
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
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.
Fern plant is a
haploid gametophyte
diploid gametophyte
diploid sporophyte
haploid sporophyte
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
Match the classes of pteridophytes given in column I with their examples given in column II and choose the correct option
| Column -I | Column-II |
|---|---|
| (Classes of pteridophytes) | (Examples) |
| A. Psilopsida | I. Selaginella |
| B. Lycopsida | II. Psilotum |
| C. Sphenopsida | III. Dryopteris |
| D. Pteropsida | IV. Equisetum |
A II; B I; C IV; D III
A I; B II; C IV; D III
A II; B I; C III; D IV
A II; B IV; C I; D III
Cycas and Adiantum resemble each other in having
seeds
motile sperms
cambium
vessels
The Natural system of classification for flowering plants was given by
Carolus Linnaeus
Bentham and Hooker
Engler and Prantl
R. H. Whittaker
Consider the following statements regarding the major pigments and stored food in the different groups of algae and choose the correct option
(i) In chlorophyceae, the stored food material is starch and the major pigments are chlorophyll-a and d.
(ii) In phaeophyceae, laminarian is the stored food and major pigments are chlorophyll-a and b.
(iii) In rhodophyceae, floridean starch is the stored food and the major pigments are chlorophyll-a, d and phycoerythrin.
(i) is correct, but (ii) and (iii) are incorrect
(i) and (ii) are correct, but (iii) is incorrect
(i) and (iii) are correct, but (ii) is incorrect
(iii) is correct, but (i) and (ii) are incorrect
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
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)
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
Pyrenoids in green algal cells are related to
starch formation
protein storage
general metabolism
enzyme secretion
A bryophyte differs from pteridophytes in having
archegonia.
lack of vascular tissue.
swimming antherozoids.
independent gametophytes.
Match column-I with column-II and select the correct answer using the codes given below.
| Column-I | Column-II |
|---|---|
| (Group of Planet Kingdom) | (Examples) |
| A. Algae | I. Solanum tuberosum |
| B. Fungi | II. Equisetum |
| C. Angiosperm | III. Cycas |
| D. Pteridophyte | IV. Chlamydomonas |
| E. Gymnosperm | V. Rhizopus |
A V; B IV; C I; D II; E III
A IV; B V; C I; D II; E III
A IV; B I; C V; D II; E III
A IV; B I; C V; D III; E II
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