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Define oxygen dissociation curve. Can you suggest any reason for its s...

Define oxygen dissociation curve. Can yo | Class 11 Biology Chapter Breathing and Exchange of Gasses, Breathing and Exchange of Gasses NCERT Solutions

Welcome to the NCERT Solutions for Class 11 Biology - Chapter Breathing and Exchange of Gasses. This page offers a step-by-step solution to the specific question from Exercise 1, Question 11: . 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 11:

Define oxygen dissociation curve. Can you suggest any reason for its sigmoidal pattern?

Answer:

The oxygen dissociation curve is a graph showing the percentage saturation of oxyhaemoglobin at various partial pressures of oxygen.

The curve shows the equilibrium of oxyhaemoglobin and haemoglobin at various partial pressures.

In the lungs, the partial pressure of oxygen is high. Hence, haemoglobin binds to oxygen and forms oxyhaemoglobin.

Tissues have a low oxygen concentration. Therefore, at the tissues, oxyhaemoglobin releases oxygen to form haemoglobin.

The sigmoid shape of the dissociation curve is because of the co-operative binding of oxygen to haemoglobin. As the first oxygen molecule binds to haemoglobin, it increases the affinity for the second molecule of oxygen to bind. Subsequently, haemoglobin attracts more oxygen.Hence Haemoglobin is a positively co-operative protein.

Other Questions of Chapter Breathing and Exchange of Gasses

Name the important parts involved in creating a pressure gradient between lungs and the atmosphere during normal respiration.

Q: How is respiration regulated?

Cigarette smoking causes emphysema. Give reason.

Q: What happens to the respiratory process in a man going up a hill?

Distinguish between
(a) IRV and ERV
(b) Inspiratory capacity and Expiratory capacity
(c) Vital capacity and Total lung capacity

A fluid filled double membranous layer surrounds the lungs. Name it and mention its important function.

Q: Have you heard about hypoxia? Try to gather information about it, and discuss with your friends.

Q: What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air?
(i) pO2 lesser, pCO2 higher
(ii) pO2 higher, pCO2 lesser
(iii) pO2 higher, pCO2 higher
(iv) pO2 lesser, pCO2 lesser

Q: Explain the process of inspiration under normal conditions.

Define the following terms?
a. Tidal volume
b. Residual volume
c. Asthma

Popular questions of class 11 Biology

Q: Describe briefly the four major groups of Protozoa.

Q: Why are living organisms classified?

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

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.

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 Breathing and Exchange of Gasses.
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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Comments

Pooja
Nov 22, 2021

Really appreciable

Pipin pradhan
Sep 05, 2019

Very useful,thanks

Kirti
May 20, 2019

Thanks

Devansh
Mar 26, 2019

Nice

Prikshit
Feb 07, 2019

Helpful

Jatanti
Feb 01, 2019

Give some short answer according to a11 class student because students are also child a little,cute and lovely child

Kashish
Jan 15, 2019

Nice answer

Ankita
Jan 15, 2019

Thnxxx fr ur crrct ans.