Category: NCERT PDF NOTES CLASS 9

Diversity in Living Organisms

“Diversity in Living Organisms” is a chapter in a science textbook for class 9 students. The chapter covers the various forms and types of living organisms that exist in the world, including plants and animals. The Topics of the chapter may be as Follow :-

  • The classification of living organisms
  • The five kingdoms of living organisms: Monera, Protista, Fungi, Plantae, and Animalia
  • Characteristics and examples of organisms in each kingdom
  • The concept of biodiversity and the importance of preserving it.
  • It also covers the concept of classification of living organisms which includes a brief history of classification, binomial nomenclature, five kingdom classification, Linnaean hierarchy and the concept of classification of living organisms

Organisms

An organism is defined as a living being that has the ability to grow, reproduce, maintain homeostasis, respond to stimuli, and adapt to its environment. Organisms may be of single-celled or multicellular. They can be classified into different groups based on their characteristics and characters. Examples of organisms include plants, animals, fungi, and microorganisms such as bacteria and protists. Organisms can be further classified into different groups, such as kingdoms, phylum, class, order, family, genus, and species.

Prokaryotes

Prokaryotes are a group of organisms that do not have a defined nucleus and other membrane-bound organelles. They are the simplest and most ancient form of life on Earth, and include bacteria and archaea.

Bacteria are single-celled microorganisms that have a wide range of shapes and sizes, and they can be found in almost every environment on Earth. They are important decomposers in many ecosystems and also play important roles in nutrient cycling. Some bacteria can also form symbiotic relationships with other organisms, such as in the human gut.
Archaea are similar to bacteria in terms of size and shape, but they have distinct genetic and metabolic characteristics that set them apart. They can also survive in Places where the temperature is high and water is high salty.
Prokaryotic cells are smaller and simpler in structure compared to eukaryotic cells, which have a defined nucleus and other membrane-bound organelles. Prokaryotic cells have a single, circular chromosome, which contains all of the cell’s genetic material. They also do not have mitochondria and chloroplasts, which are found in eukaryotic cells.

Eukaryotes

Eukaryotes are a group of organisms that have a defined nucleus and other membrane-bound organelles. They are more complex in structure than prokaryotes, and include organisms such as plants, animals, fungi, and protists.

All the plants that are around us are multicellular organisms. As the plant can grow, reproduce and generate. They have cell walls, chloroplasts and a variety of other organelles.
Also all the Animals are the Multicellular organisms as they have ability to move, action to stimuli, and they also reproduce or give births to their ones.

The eukaryotes organisms can further be classified into sub groups, that are :-

  • Unicellular Eukaryotes Organsims
  • Multicellular Eukaryotes Organsims

After Understanding the Diversity in Living in Organisms you can also go through the next chapter of class 9 Science, the PDF link of which is given below:-

Class 9 Science Chapter – 8 :- Motion

Class 9 Science Tissue

The topics covered in Class 9 Science Chapter 6 Tissue PDF Notes typically include:

  • Introduction to tissues and their types: The Class 9 Science Chapter 6 Tissue begins with an introduction to the concept of tissue, its importance and the different types of tissues found in plants and animals.
  • Plant Tissues: The chapter covers the three types of plant tissues: dermal, ground, and vascular. It explains the structure and function of each type of tissue and how they work together to support the plant’s growth and survival.
  • Animal Tissues: The chapter also covers the four types of animal tissues: epithelial, connective, muscle, and nervous. It explains the structure and function of each type of tissue and their role in maintaining the integrity of the animal body.
  • Tissue repair and regeneration: This section discusses the process of tissue repair and regeneration in animals and plants. It covers the mechanisms by which cells divide and differentiate to form new tissues.
  • Tissue organization in animals: The chapter explains the organization of tissues in animals, from simple to complex, like Epithelial tissue, Connective tissue,Muscular tissue, Nervous tissue.
  • Conclusion: This chapter of Class 9 Science TISSUE concludes with a summary of the key concepts covered in the chapter and their importance in the functioning of plants and animals.

The PDF Notes of the Chapter 6 of class 9 Science “Tissue” is given above. These PDF Notes helps the student to understand the different types of Tissues of Plants and Animals. The plant tissue and Animal tissues both have the different works in the plant body as well as in Animal body. This chapter helps to understand the Tissues and Working of Plant tissues.

Plant Tissue

Plant tissues are groups of cells that perform specific functions in a plant. They are organized into different types based on their structure, function, and location in the plant. Plant Tissues are further divided into two main parts :- Meristematic Tissues and Permanent Tissues.

Meristematic Tissues

Meristematic tissue is a type of plant tissue that is responsible for growth and cell division. It is composed of actively dividing cells that are capable of differentiating into other types of plant tissues. There are three types of meristematic tissue in plants:

Apical meristems: These are located at the tips of roots and shoots and are responsible for the elongation of the plant. They give rise to new cells that differentiate into the various tissues of the root or shoot.

Lateral meristems: These are located along the lateral sides of the plant and are responsible for increasing the diameter of the plant. They give rise to new cells that differentiate into secondary xylem and phloem.

Intercalary meristems: These are located at the base of leaves and some stem, and are responsible for the growth of plants in length. They give rise to new cells that differentiate into the various tissues of the stem or leaf.

These meristematic tissues are found in different parts of the plant and are responsible for the plant growth and development.

Permanent Tissues

Permanent tissue is a type of plant tissue that is formed from cells that have stopped dividing and have taken on a specific function. There are two main types of permanent tissue in plants:

Simple permanent tissue: This type of tissue is composed of similar cells that perform the same function. Examples of simple permanent tissue include parenchyma, collenchyma, and sclerenchyma.

Complex permanent tissue: This type of tissue is composed of different types of cells that perform different functions. Examples of complex permanent tissue include xylem and phloem.

Parenchyma: Parenchyma is the most common type of simple permanent tissue. Its cells are generally isodiametric, thin-walled and have a large central vacuole. It is found in the mesophyll of leaves, cortex of stem and root, and in the pulp of fruits.

Collenchyma: Collenchyma tissue is composed of elongated cells with thick walls. It provides structural support to the plant, especially in young and expanding regions such as stems and leaves.

Sclerenchyma: Sclerenchyma tissue is composed of cells with thick and lignified walls. It provides mechanical support to the plant and is found in the stem and other parts of the plant.

Xylem: Xylem is the complex permanent tissue responsible for the transport of water and minerals from the roots to the rest of the plant. It is composed of several types of cells including tracheids, vessels, and xylem fibers.

Phloem: Phloem is the complex permanent tissue responsible for the transport of sugars and other organic compounds throughout the plant. It is composed of several types of cells including sieve-tube elements, companion cells, and phloem fibers.

Animal Tissue

Animal tissues are groups of cells that perform specific functions in an animal’s body. These Tissues are categorised into different types based on their structure, function, and location in the animal’s body. Four main types of animal tissues are : epithelial, connective, muscle, and nervous.

Epithelial tissue: Epithelial tissue lines the surfaces of the body and forms glands. It provides a barrier between the body and the environment, and also helps in the absorption, secretion and excretion.

Connective tissue: Connective tissue provides support, protection and holds organs in place. It includes various types like loose, dense and special connective tissue like cartilage, bone, and blood.

Muscle tissue: Muscle tissue is responsible for movement. It is of three types: skeletal, smooth and cardiac. Skeletal muscle is attached to bones. It is responsible for voluntary movement and cardiac muscle is found in the heart and is responsible for pumping blood.

Nervous tissue: Nervous tissue is responsible for sensing and responding to stimuli. These Tissues are composed of neurons and supporting cells called glial cells. It forms the brain, spinal cord, and nerves.

Additionally, students will also learn about the importance of tissues in the growth and development of animals, the process of tissue repair, and how different tissues work together to support the overall functioning of the animal body

After reading this Chapter you can through the next chapter of the class 9 Science Chapter – 7 Diversity in Living Organisms

Class 9 science Fundamental Unit of Life : Cell

The smallest unit of Life that can live on its own and that makes up all living organisms and tissues. The cells are the smallest unit of life. By reading the PDF notes of Fundamental Unit of Life : Cell which is given below. You are able to distinguish between the cells and different types of Cells, Different parts or Components of Cells.

In Class 9 Science, Chapter 5, “Fundamental Unit of Life: Cell”, students learn about the basic structure and functions of cells. Cells are the building blocks of all living organisms. The chapter covers the history of cell discovery, The different types of cells (eukaryotic and prokaryotic), And the various organelles and their functions within a cell. Topics such as cell division (mitosis and meiosis), cell membrane structure and transport, and cell communication are also discussed

List of Topics of Class 9 Science Chapter 5 Fundamental Unit of life cells

Here are some of the main topics that are covered in Class 9 Science, Chapter 5, “Fundamental Unit of Life: Cell”:

  • Introduction to cells and the history of cell discovery
  • Types of cells (eukaryotic and prokaryotic)
  • Structural and functional organization of a cell
  • Cell membrane structure and transport
  • Cell organelles and their functions
  • Mitosis and meiosis
  • Cell communication and coordination
  • Tissue, organ and organ system

The cell is considered the fundamental unit of life because it is the basic structural and functional unit of all living organisms. Cells are the building blocks of life, and all living things are made up of one or more cells. Cells are incredibly complex and perform a wide range of functions that are necessary for the survival and growth of an organism. They carry out metabolic reactions, replicate DNA, respond to stimuli, and communicate with other cells. The discovery of the cell and its structure and function were key milestones in the field of biology, and the study of cells is known as cell biology.

Introduction to cells and the history of cell discovery

The cell is the basic unit of life, and all living organisms are made up of one or more cells. The history of cell discovery can be traced back to the 17th century when Robert Hooke first observed and described cells in cork using a microscope. However, it was not until the 19th century that scientists began to fully understand the importance and fundamental nature of the cell.

In 1838, Matthias Schleiden and Theodor Schwann proposed the “cell theory,” stating that all living organisms are composed of cells and that cells are the basic unit of life. This theory was later expanded upon by Rudolf Virchow, who stated that all cells come from pre-existing cells.

In 1855, Rudolf Virchow published the first detailed description of the cell, and in 1858, Robert Brown described the nucleus, which was later discovered to be the control center of the cell.

In 1879, Walther Flemming discovered the process of mitosis, which is the process by which a single cell divides to form two identical daughter cells.

In the 20th century, technological advancements such as the electron microscope allowed scientists to further study the structure and function of cells. The discovery of DNA and the understanding of genetic information also advanced the field of cell biology.

Today, the study of cells continues to be a vital and active field of research, as scientists continue to uncover new information about the complexity and intricacies of the cell

Types of cells (eukaryotic and prokaryotic)

There are two main types of cells: eukaryotic and prokaryotic. Eukaryotic cells are cells that have a membrane-bound nucleus and other membrane-bound organelles, such as mitochondria and chloroplasts. These cells are found in all multicellular organisms, including plants, animals, and fungi. Prokaryotic cells, on the other hand, do not have a membrane-bound nucleus or organelles. They are smaller in size and are found in single-celled organisms such as bacteria and archaea.

Structural and functional organization of a cell

The structural and functional organization of a eukaryotic cell is divided into three main parts: the plasma membrane, the cytoplasm, and the nucleus.

The plasma membrane, also known as the cell membrane, is a thin, semi-permeable barrier that surrounds the cell and separates its internal environment from the external environment. It is made up of a phospholipid bilayer and various proteins that act as receptors and channels for the cell to communicate and exchange materials with its surroundings.

The cytoplasm is the gel-like substance that fills the cell and is located within the plasma membrane. It contains various organelles, such as the mitochondria, endoplasmic reticulum, and Golgi apparatus, which carry out specific functions to support the cell’s survival.

The nucleus is the largest organelle in the cell and contains the cell’s genetic material, or DNA, in the form of chromosomes. It is surrounded by a double-membraned nuclear envelope and contains a nucleolus, where ribosomes are synthesized. The nucleus controls the cell’s growth and reproduction through the regulation of gene expression.

After understanding the concepts of this Chapter “Fundamental Unit of Life : Cell” You can go through the PDF Notes of the next chapter.

Link of which is given below :- Chapter – 6 :- TISSUE

Class 9 Science Structure of Atom

Structure of Atoms : Do you know how an Atom look like? What are the different elements or parts of an Atom? Well No one knows how an Atom look like. So in this chapter of class 9 science ” The Structure of the Atom” we will know all about the Atoms.

After reading thoroughly the PDF Notes of Structure of the atom, you will able to distinguish the Atoms and its different parts like – Protons, Neutrons, Electrons etc. This chapter includes more on the topics like :- Atomic Structure, Atomic Mass, Atomic Number, Isotopes and Isobars etc.

Class 9 science Chapter 4 Structure of the Atoms PDF Notes is given below :

Chapter 4 Structure of the Atoms

The Atom is a smallest particle that can not be destroyed or break down further. Also an atoms does not change with the chemical reaction. All atoms have an identical chemical properties, Atomic Number, Atomic mass. But Atoms of different elements have different Chemical properties, Atomic number and Atomic Masses.

This Chapter covers the following topics:

Discovery of electrons, protons and neutrons
Thomson’s atomic model
Rutherford’s atomic model
Bohr’s atomic model
Quantum mechanical model of the atom
Atomic number, mass number and isotopes
Electronic configuration of atoms
It aims to explain the structure of atoms, including the relative locations and properties of the electrons, protons and neutrons that make up atoms, and how these subatomic particles interact. Additionally, it explains the different models of the atom that have been proposed throughout history, and how they have helped scientists understand the nature of atoms

Main topics in The structure of atoms

The main topics of Class 9 Science Structure of Atoms chapter are:

  1. Discovery of electrons, protons, and neutrons
  2. Thomson’s atomic model
  3. Rutherford’s atomic model
  4. Bohr’s atomic model
  5. Quantum mechanical model of the atom
  6. Atomic number, mass number and isotopes
  7. Electronic configuration of atoms
  8. Atomic and ionic radii
  9. Valency
  10. Chemical bonding
  11. Metallic and covalent bonding
  12. Hydrogen bonding
  13. Van der Waals forces

This chapter helps students to understand the structure and properties of atoms, the subatomic particles that make up atoms, and how they interact with each other. It also covers the different models of the atom that have been proposed throughout history and how they have helped scientists understand the nature of atoms. Finally, it covers chemical bonding and its importance in the formation of compounds and molecule

After reading this chapter, you can go through the next chapter of class 9 Science :- Fundamental Unit of Life : Cell

Class 9 Science Atoms and Molecules

Atoms And Molecules chapter of class 9 science is based on the study of different typed Atoms and Molecules. While studying in the class 9 science chapter it is important to know about these topics which includes:-

Laws of Chemical combinations

Dalton’s Atomic theory

What is an Atom?

What is an Molecule?

Writing a Chemical Formulae

Law of conservation of Mass etc

Class 9 science chapter 3 is typically titled “Atoms and Molecules” and covers the following concepts:

  • The concept of atoms as the building blocks of matter.
  • The discovery of atoms and molecules and the contributions of scientists like John Dalton, J.J Thomson, and Ernest Rutherford to the atomic theory.
  • The structure of atoms, including the nucleus and electrons and the concept of atomic number and atomic mass.
  • The concept of isotopes and their properties.
  • The concept of molecules and the difference between atoms and molecules.
  • The concept of chemical bonding, including ionic, covalent, and metallic bonding.
  • The concept of chemical formulas, including molecular and empirical formulas.
  • The concept of chemical equations and the law of conservation of mass.
  • The concept of acids, bases, and salts and their properties.
  • The concept of chemical reactions and the formation of new substances.
  • It may vary based on the curriculum and board you are following.

The main topics covered in the chapter “Atoms and Molecules” are:

  • Definitions of the Atoms and Molecules.
  • Atomic theory and the discovery of atoms
  • Structure of atoms, including the nucleus and electrons
  • Atomic number and atomic mass
  • Isotopes and their properties
  • Difference between atoms and molecules
  • Types of chemical bonding, including ionic, covalent and metallic bonding
  • Chemical formulas, including molecular and empirical formulas
  • Chemical equations and the law of conservation of mass
  • Acids, bases, and salts and their properties
  • Chemical reactions and the formation of new substances
  • Molecular mass and molar mass
  • Avogadro’s number and molar volume of gases
  • Collision theory and rate of chemical reactions


It may vary based on the curriculum and board you are following.

After analyses of this chapter you can also go through the PDF Notes of next Chapter of Class 9 Science ” Chapter -4 Structure of the Atom.”

Class 9 PDF Notes

Is Matter Around Us Pure ? This chapter of Class 9 Science is basically based on the concept that the matter, that found around us is pure or not. So here are the PDF Notes by reading which a student can understand the different states of matters around us. Thoroughly go through the Pdf given below to understand the topic of Class 9 Science Chapter 2 Is Matter Around Us Pure.

Class 9 science chapter 2 is typically titled “Is Matter Around Us Pure” and covers the following concepts:

  • Introduction to the concept of pure and impure substances, and the difference between the Matter Around us.
  • Physical and chemical methods of separating Pure forms of Matter, such as filtration, sedimentation, centrifugation, distillation, and chromatography.
  • The concept of homogeneous and heterogeneous mixtures and the methods used to distinguish between them.
  • The physical and chemical properties of pure Matters, including the concept of elements, compounds, and mixtures.
  • The concept of solutions, suspensions, and colloids and the methods used to distinguish between them.
  • The concept of concentration of solutions, including molarity, molality, and normality.
  • The concept of water as a solvent and its importance in various natural processes.
  • The concept of acids, bases, and neutral substances and the difference between them.
  • The concept of pH and how it is used to measure the acidity or basicity of a substance.
  • The concept of chemical reactions and the formation of new substances.

It may vary based on the curriculum and board you are following.

Here are some tips for reading the chapter for best results:

Preview the chapter: Before you start reading, take a quick look at the chapter’s headings “Is Matter Around Us Pure” and subheadings to get an idea of what the chapter covers. This will help you understand the main topics and how they are organized.
Read actively: As you read, take notes, underline important information, and ask questions. This will help you stay engaged and understand the material better.
Summarize the main points: After reading a section, try to summarize the main points in your own words. This will help you retain the information and understand the main concepts.
Practice problem-solving: Try to solve the numerical problems given in the chapter, it will help you to understand the concept and apply it in the real world.
Illustrate the concepts: Try to draw diagrams or illustrations to help you visualize the concepts discussed in the chapter.
Review the chapter: After you have finished reading the chapter, go back and review the main points. This will help you solidify your understanding of the material.
Practice with sample papers and questions papers: Practice with sample papers and question papers to understand the pattern and level of questions that can be expected in the exams.
Take help from teacher or tutor: If you have any difficulties with the chapter, don’t hesitate to ask your teacher or tutor for help.

After reading this chapter you can also go through the Class 9 Science Chapter 3 “ATOMS AND MOLECULES”

Matter in our surrounding notes

Matter in our surrounding notes is very important for those students who are preparing notes for class 9 science.
These PDF notes for Class 9 students typically contain information and concepts covered in the curriculum for that grade level. These notes can be created by teachers, educational institutions, or even students themselves. They can be used as a study aid for exams, homework assignments, and class discussions. These notes can include text, images, and diagrams to help explain complex concepts.

For downloading the Class 9 Science pdf notes follow the PDF given below :-

Chapter 1 Matter in our surrounding notes

This is a science topic typically covered in Class 9. PDF notes on this topic would likely include information on the following concepts:

Definition of matter: Matter is anything that has mass and takes up space.

States of matter: Matter can exist in three states- solid, liquid and gas.

Physical and chemical properties of matter: Physical properties, such as density, color, and melting point, do not change when matter changes form. Chemical properties, such as flammability and reactivity, do change when matter changes form.

Changes of state: The process by which matter changes from one state to another is called a change of state. Examples include melting, freezing, boiling, and condensation.

Mixtures and compounds: Mixtures are made up of two or more substances that are not chemically combined, while compounds are made up of two or more elements that are chemically combined.

Separation of mixtures: Different methods of separation such as filtration, centrifugation, evaporation, distillation, and chromatography.

The gas laws: Charles’s Law, Boyles Law, and Gay-Lussac’s Law, which describe the relationship between the pressure, volume, and temperature of a gas.

These notes would be supported by diagrams, images, and examples to help students understand and remember the concepts better.

After this we will learn about the topic “IS MATTER AROUND US PURE”

How to differentiate matters in our surrounding

There are several ways to determine the different types of matter in our surroundings:

Observation: By using our senses, we can observe the appearance, texture, and behavior of matter to determine its properties. For example, we can observe that a rock is hard and a liquid is flowing.

Measurement: We can measure the properties of matter such as density, mass, and volume to determine its identity. For example, we can measure the density of a substance to determine if it is a metal or a nonmetal.

Experimentation: We can conduct experiments to observe the chemical reactions and changes in matter to determine its identity. For example, we can conduct a flame test to determine the presence of certain metallic ions in a sample.

Analysis: We can also use analytical techniques such as spectroscopy, chromatography and microscopy to identify the different types of matter.

Comparison: We can compare the properties of a substance with known substances to determine its identity. For example, we can compare the taste, smell, and appearance of a fruit to determine if it is an apple or a pear.

These methods can be used individually or in combination to identify the different types of matter in our surroundings.