Question
Question: Which one of the following is an example of chlorophyllous thallophyte? A. Volvariella B. Spirog...
Which one of the following is an example of chlorophyllous thallophyte?
A. Volvariella
B. Spirogyra
C. Nephrolepis
D. Gnetum
Solution
Hint:- Thallophyta includes the most primitive and simple plants with unicellular or multicellular thallus. The plant body of a thallophyta is not differentiated into stem, leaves and roots. These are traditionally divided into four groups- Algae, fungi, bacteria and lichens.
Complete answer: Volvariella belongs to the division Basidiomycota of fungi. These are commonly known as ‘paddy straw mushrooms’. Basidiomycetes includes the most advanced and most commonly seen fungi. The motile structure is absent in these fungi and they are the best decomposers of wood. They decompose both lignin and cellulose in wood.
Spirogyra is a green algae with a thallus-like plant body. The cells of the Spirogyra may possess one or more spiral shaped chloroplasts. The chloroplasts have 2-20 thylakoid lamellae. In Spirogyra, the haploid gametophyte stage is dominant and multicellular whereas the diploid phase is represented only by the zygote or zygospore. So they have a haplontic life.
Ferns are widely distributed in the world. The plant body is differentiated into underground stem, roots and aerial shoots with leaves. The leaves may be simple or compound which arise alternately on the upper side of the rhizome. They may be homosporous or heterosporous. Nephrolepis is an example of ferns.
Gnetum belongs to the Gymnosperm class of the plant kingdom. They are tropical trees, shrubs and lianas in habit. They have well developed xylem elements and their leaves are rich in bioactive compounds like stilbenes and flavonoids.
So the correct answer is 2. Spirogyra.
Note:- Algae are predominantly aquatic in habit and have chlorophyll pigment. Thus they are photoautotrophic in their mode of nutrition and they perform photosynthesis for preparing their food.