Topics
Matter in Our Surroundings
- Matter (Substance)
- Characteristics of Particles (Molecules) of Matter
- The Solid State
- The Liquid State
- The Gaseous State
- Plasma
- Bose-einstein Condensate
- Heat and change of physical state
- Concept of Evaporation
- Concept of Melting (Fusion)
- Concept of Boiling (Vaporization)
- Concept of Sublimation
- Concept of Freezing (Solidification)
- Concept of Condensation (Liquefaction)
- Concept of Desublimation (Deposition)
Is Matter Around Us Pure
- Matter (Substance)
- Natural substances
- Mixture
- Types of Mixtures
- Solution
- Concentration of a Solution
- Suspension Solution
- Colloidal Solution
- Evaporation Method
- Solvent Extraction (Using a Separating Funnel Method)
- Sublimation Method
- Chromatography Method
- Simple Distillation Method
- Fractional Distillation Method
- Crystallisation Method
- Classification of Change: Physical Changes
- Chemical Reaction
- Pure Substances
- Compound
- Elements
Atoms and Molecules
- History of Atom
- Laws of Chemical Combination
- Law of Conservation of Mass
- Law of Constant Proportions (Law of Definite Proportions)
- Dalton’s Atomic Theory
- Atoms: Building Blocks of Matter
- Symbols Used to Represent Atoms of Different Elements
- Atomic Mass
- Relative Atomic Mass (RAM)
- Molecules
- Classification of Molecules
- Difference Between Atoms and Molecules
- Ions (Radicals) and Its Types
- Chemical Formula or Molecular Formula
- Molecular Mass
- Formula Unit Mass
- Mole Concept
- Atoms and Molecules Numericals
Structure of the Atom
- Existence of Charged Particles in Matter
- Atoms: Building Blocks of Matter
- Discovery of Charged Particles in Matter
- Protons (p)
- Electrons (e)
- Neutrons (n)
- J. J. Thomson’s Atomic Model
- Advantage and Limitations of Thomson’s Atomic Model
- Lord Rutherford’s Atomic model
- Limitations of Rutherford’s Atomic Model
- Neils Bohr’s Model of an Atom
- Electronic Configuration of Atom
- Valency
- Different Ways to Determine Valency
- Atomic Number (Z), Mass Number (A), and Number of Neutrons (n)
- Atomic Mass
- Isotopes
- Uses of Radioactive Isotopes
- Isobars
- Atoms and Molecules Numericals
The Fundamental Unit of Life
- Cell: Structural and Functional Unit of Life
- The Invention of the Microscope and the Discovery of Cell
- Cell Theory
- Organisms Show Variety in Cell Number, Shape and Size
- Prokaryotic and Eukaryotic Cell
- Simple Diffusion
- Concept of Osmosis
- Osmotic Pressure
- Structure of the Cell
- Plasma Membrane
- Semi-permeable Membrane (Cell Membrane)
- Cell Wall - “Supporter and Protector”
- Nucleus - “Brain” of the Cell
- Cytoplasm - “Area of Movement”
- Endoplasmic Reticulum (ER)
- Golgi Apparatus - "The delivery system of the cell"
- Lysosome - “Suicidal Bag”
- Mitochondria - “Power House of the Cell”
- Plastids
- Non-living Substances Or Cell Inclusion
- Plant Cell and Animal Cell
- Cell Division: an Essential Life Process
Tissues
- Tissues - “The Teams of Workers”
- Plant and Animals Tissue
- Plant Tissues
- Meristems or Meristematic Tissues
- Permanent Tissue
- Simple Permanent Tissues (Supporting Tissue)
- Complex Permanent Tissues
- Complex Permanent Tissue: Xylem Structure and Function (Conducting Tissue)
- Complex Permanent Tissue: Phloem Structure and Function (Conducting Tissue)
- Animal Tissues
- Epithelial Tissue
- Connective Tissue
- Muscular Tissue
- Nervous Tissue
Motion
- Motion and Rest
- Describing Motion
- Motion Along a Straight Line
- Types of Motion
- Measuring the Rate of Motion - Speed with Direction
- Rate of Change of Velocity
- Distance and Displacement
- Displacement - Time Graph Or Distance - Time Graph
- Velocity - Time Graphs
- Equations of Motion by Graphical Method
- Derivation of Velocity - Time Relation by Graphical Method
- Derivation of Displacement - Time Relation by Graphical Method
- Derivation of Displacement - Velocity Relation by Graphical Method
- Uniform Circular Motion (UCM)
- Motion (Numerical)
Diversity in Living Organisms
- Biodiversity
- Biological Classification
- Classification of Living Organisms
- Taxonomic Hierarchy of Living Organisms: Unit of Classification
- Five Kingdom Classification
- Kingdom Monera
- Kingdom Protista
- Kingdom Fungi
- Classification of Kingdom Plantae
- Kingdom Animalia
- Differences Between Plantae (Plants) and Animalia (Animals)
- Classification of Kingdom Plantae
- Kingdom Plantae: Thallophyta (Algae)
- Kingdom Plantae: Thallophyta (Fungi)
- Division II- Bryophytes
- Division III- Pteridophytes
- Division I-Gymnosperms
- Division II- Angiosperms
- Kingdom Animalia
- Phylum: Porifera
- Phylum: Cnidaria/Coelenterata
- Phylum: Platyhelminthes
- Invertebrate: Phylum Nematoda
- Phylum: Annelida
- Phylum: Arthropoda
- Phylum: Mollusca
- Phylum: Echinodermata
- Subphylum: Prochordata
- Chordata: Vertebrata
- Invertebrata and Vertebrata
- Taxonomy and Systematics
- Nomenclature
Force and Laws of Motion
Gravitation
Work and Energy
Sound
- Sound
- Production of Sound
- Propagation of Sound
- Sound Need a Medium to Travel
- Sound Waves Are Longitudinal Waves
- Characteristics of a Sound Wave
- Speed of Sound (Velocity of Sound)
- Reflection of Sound
- Echoes
- Reverberation
- Uses of Multiple Reflection of Sound
- Range of Hearing in Humans
- Ultrasonic Sound Or Ultrasound
- SONAR
- Human Ear
- Sound (Numerical)
Improvement in Food Resources
- Improvements in Food Resources
- Improvement in Crop Yields
- Crop Variety Improvement
- Crop Production Improvement
- Crop Protection Management
- Methods to Replenish Nutrients in Your Soil
- Manuring (Biomanuring)
- Fertilizers
- Improved methods of agriculture
- Agricultural Assistance Programme
- Animal Husbandry (Livestock)
- Dairy Farming
- Poultry Farming
- Pisciculture (Fish Farming)
- Apiculture (Bee Farming)
Why Do We Fall ill
- Health
- Disease
- Categories of Disease
- Acute and Chronic Diseases
- Causes of Disease
- Communicable Or Infectious Diseases
- Infectious Agents
- Manifestation of Diseases
- Modes of Transmission of Diseases
- Organ-specific and Tissue-specific Manifestations
- Principles of Prevention of Diseases
- Principles of Treatment of Diseases
Natural Resources
- Natural Resources
- Biosphere: The Domain of Life
- Air is a Mixture
- Atmosphere and Its Layers
- Wind: The Movement of Air
- Rain
- Water: Our Lifeline
- Where Do We Get Water From?
- Availability of Water
- Importance of Water
- Water Pollution and Its Causes
- Mineral Riches in the Soil
- Biogeochemical Cycle
- Water Cycle
- Nitrogen Cycle
- The Carbon Cycle
- The Oxygen Cycle
- Ozone
- Ozone Layer Depletion
Notes
The Invention of the Microscope and the Discovery of Cell:
Cell Biology History - A Timeline |
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1665 | Robert Hooke had successfully invented the microscope. Because of this discovery, Robert Hooke was the first one to have a close look of a cell that appears to be. While examining a thin slice of cork, Robert Hooke saw that the cork resembled the structure of a honeycomb consisting of many little compartments. Cork is a substance that comes from the bark of a tree. This was in the year 1665 when Hooke made this chance observation through a self-designed microscope. Robert Hooke called these boxes cells. Cell is a Latin word for ‘a little room’. However, the cell walls observed by Hooke gave no indication of the nucleus and other organelles found in most living cells. |
Robert Hooke |
1674 |
Leeuwenhoek (1674), with the improved microscope, discovered the free-living cells in pond water for the first time. |
Antonie van Leeuwenhoek |
1825 | French scientist Francoise Raspail established one of the Concepts of cell theory: that all cells arise from pre-existing cells. The basis of this was the witnessing of binary fission under a microscope wherein a single cell divided into two daughter cells. |
François-Vincent Raspail |
1831 |
It was Robert Brown in 1831 who discovered the nucleus in the cell. |
Robert Brown |
1839 |
Purkinje in 1839 coined the term ‘protoplasm’ for the fluid substance of the cell. |
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Basic optical parts of a microscope include -
- Eyepiece: The lens from which the viewer looks through to see the specimen. The eyepiece usually contains a 10X or 15X power lens.
- Coarse adjustment: It brings the specimen into general focus.
- Fine adjustment: It focuses and increases the detail of the specimen.
- Illumination: It is the light source for a microscope. Older microscopes used mirrors to reflect light from an external source up through the bottom of the stage. Most microscopes now use a low-voltage bulb.
- Condenser: Gathers and focuses light from the illuminator onto the specimen being viewed.
Example
Answer the following question.
Who discovered cells, and how?
Robert Hooke discovered the cells. He saw that the cork resembled the structure of a honeycomb consisting of many little compartments. Cork is a substance which comes from the bark of a tree. This was in the year 1665 when Hooke made this chance observation through a self-designed microscope. Robert Hooke called these boxes cells. In this way, he discovered the cells.