What is the nature of cell-walls in diat | Class 11 Biology Chapter Biological Classification, Biological Classification NCERT Solutions

Welcome to the NCERT Solutions for Class 11 Biology - Chapter Biological Classification. This page offers a step-by-step solution to the specific question from Exercise 1, Question 3: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 3: What is the nature of cell-walls in diatoms?

Answer:

The cell walls construction of diatoms is known as Frustule which consists of two thin overlapping shells fitting into each other just as a soap-box. Their walls are made up of silica. When the diatoms die, the silica in their cell walls gets deposited in the form of diatomaceous earth. This diatomaceous earth is very soft and quite inert. It is used in filtration of oils, sugars, and for other industrial purposes.

Other Questions of Chapter Biological Classification

Q: Describe briefly the four major groups of Protozoa.

Suppose you accidentally find an old preserved permanent slide without a label. In your effort to identify it, you place the slide under microscope and observe the following features :-
a. Unicellular
b. Well defined nucleus
c. Biflagellate–one flagellum lying longitudinally and the other transversely.
What would you identify it as? Can you name the kingdom it belongs to?

Diatoms are also called as ‘pearls of ocean’, why? What is diatomaceous earth?

Q: State two economically important uses of: (a) Heterotrophic bacteria (b) Archaebacteria

Q: Give a comparative account of the classes of Kingdom Fungi under the following:
(i) Mode of nutrition
(ii) Mode of reproduction

Q: What are the characteristic features of Euglenoids?

Fungi are cosmopolitan. Write the role of fungi in your daily life.

Q: Find out what do the terms algal bloom and red-tides signify.

Q: What do the terms phycobiont and mycobiont signify?

Biological classification is a dynamic and ever evolving phenomenon which keeps changing with our understanding of life forms. Justify the statement taking any two examples.

Popular questions of class 11 Biology

Q: Why are living organisms classified?

Q: What is the difference between direct and indirect development?

Define a taxon. Give some examples of taxa at different hierarchical levels.

Q: Describe the important properties of enzymes.

What are the steps involved in formation of a root nodule?

Q: Illustrate the taxonomical hierarchy with suitable examples of a plant and an animal.

Q: How is a key helpful in the identification and classification of an organism?

Q: What is stomatal apparatus? Explain the structure of stomata with a labelled diagram.

Q: Define and understand the following terms:
(i) Phylum
(ii) Class
(iii) Family
(iv) Order
(v) Genus

Q: Write a note on economic importance of algae and gymnosperms.

Recently Viewed Questions of Class 11 Biology

Name the pathological condition when uncontrolled cell division occurs.

Aquatic animals generally are ammonotelic in nature where as terrestual forms are not. Comment.

Name the cells/tissues in human body which
a. exhibit ameboid movement
b. exhibit ciliary movement

Q: How is the study of plant anatomy useful to us?

How do you distinguish between a skeletal muscle and a cardiac muscle?

Q: Explain the term thecodont and diphyodont.

Why earthworm is called the friend of farmer?

Q: Draw the labelled diagram of the following:
(i) Gram seed
(ii) V.S. of maize seed

Which of the following is correct:
(a) Cells of all living organisms have a nucleus.
(b) Both animal and plant cells have a well defined cell wall.
(c) In prokaryotes, there are no membrane bound organelles.
(d) Cells are formed de novo from abiotic materials.

Mitosis results in producing two cells which are similar to each other. What would be the consequence if each of the following irregularities
occur during mitosis?
a. Nuclear membrane fails to disintegrate
b. Duplication of DNA does not occur
c. Centromeres do not divide
d. Cytokinesis does not occur.

Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

Read the question carefully and focus on the core concept being asked.
Reference examples and data from the chapter when answering questions about Biological Classification.
Review previous year question papers to get an idea of how such questions may be framed in exams.
Practice answering questions within the time limit to improve your speed and accuracy.
Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Sep 14, 2019

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Aug 20, 2019

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Jun 25, 2019

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