Topics
Chemical Substances - Nature and Behaviour
Carbon Compounds
- Carbon: a Versatile Element
- Bonding in Carbon - Covalent Bond
- Carbon: a Versatile Element
- Saturated and Unsaturated Carbon Compounds
- Chains, Branches and Rings of Carbon Compound
- Homologous Series of Carbon Compound
- Nomenclature of Carbon Compounds
- Chemical Properties of Carbon Compound
- Chemical Properties of Carbon Compound
- Chemical Properties of Carbon Compound
- Ethanol
- Ethanoic Acid
- Soap
- Chemical Properties of Carbon Compound
Metals and Non Metals
- Types of Element: Metals
- Types of Elements: Non-metal
- Chemical Properties of Metals: When Metals Are Burnt in Air
- Chemical Properties of Metals: When Metals React with Water
- Chemical Properties of Metals: When Metals React with Acids
- Chemical Properties of Metals: Metals React with Solutions of Other Metal Salts
- Chemical Properties of Metals: Reactivity Series
- Reaction of Metals with Non-metals
- Formation and Properties of Ionic Compounds
- Types of Element: Metals
- Extraction of Metals from Ore
- Enrichment of Ores
- Extracting Metals Low in the Activity Series
- Extracting Metals in the Middle of the Activity Series
- Extracting Metals Towards the Top of the Activity Series
- Refining of Metals
- Corrosion of Metals and Its Prevention
- Covalent (Molecular) Bond
Periodic Classification of Elements
Acids, Bases and Salts
- Acids
- Bases (Alkalis)
- Indicators
- Chemical Properties of Acids and Bases
- Reaction of Acids and Bases with Metals
- Reaction of Acids with Metal Carbonates and Hydrogencarbonates
- Reaction of Metallic Oxides with Acids
- Reaction of a Non-metallic Oxide with Base
- Acids and Bases React with Each Other
- Acid Or a Base in a Water Solution
- Strength of Acidic Or Basic Solutions
- Salts
- Salts
- Chemicals from Common Salt (Uses of Salt)
- Preparation and Uses of Sodium Hydroxide
- Preparation and Uses of Bleaching Powder
- Preparation and Uses of Baking Soda
- Preparation and Uses of Washing Soda
- Preparation and Uses of Plaster of Paris
Chemical Reactions
- Classification of Change: Physical Changes
- Classification of Change: Chemical Changes
- Classification of Change: Chemical Changes
- Chemical Equation
- Chemical Equation
- Direct Combination (or Synthesis)
- Decomposition Reactions
- Single Displacement Reactions
- Double Displacement Reaction
- Oxidation and Reduction
- Corrosion of Metals and Its Prevention
- Concept of Rancidity
- Endothermic and Exothermic Reactions
World of Living
Heredity and Evolution
- Evolution and Classification - Introduction
- Accumulation of Variation During Reproduction
- Heredity - Inherited Traits
- Rules for the Inheritance of Traits - Mendel’S Contributions
- Sex Determination in Humans
- Concepts of Evolution
- Evolution - Acquired and Inherited Traits
- Speciation
- Heredity and Evolution
- Evolution and Classification - Tracing Evolutionary Relationships
- Evolution and Classification - Fossils
- Evolution by Stages
- Human Evolution
Reproduction
- Reproduction in Plant
- Reproductive Health - Need and Methods of Family Planning
- Modes of Reproduction Used by Single Organisms - Fission
- Modes of Reproduction Used by Multicellular Organisms - Fragmentation
- Modes of Reproduction Used by Multicellular Organisms - Regeneration
- Modes of Reproduction Used by Single Organisms - Budding
- Modes of Reproduction Used by Multicellular Organisms - Vegetative Propagation
- Modes of Reproduction Used by Multicellular Organisms - Spore Formation
- Sexual Reproduction in Animals
- Sexual Reproduction in Flowering Plants
- Human Reproductive System
- Reproduction in Plant
- Sexually Transmitted Diseases
Control and Co-ordination in Animals and Plants
- Control and Co-ordination Introduction
- Tropic Movements in Plants
- Coordination in Plants - Movement Due to Growth
- Coordination in Plants - Immediate Response to Stimulus
- Hormones in Animals
- Control and Co-ordination in Animals
- Importance of Variation
- Animals – Nervous System
- Human Brain - Voluntary Action
- Human Brain - Involuntary Action
- Human Brain - Reflex Action
- Control and Co-ordination Questions
Life Processes
Natural Phenomena
- Refraction of Light
- Spherical Mirrors
- Concave Mirror
- Convex Mirror
- Concave Mirror
- Convex Mirror
- Sign Convention for Reflection by Spherical Mirrors
- Linear Magnification (M) Due to Spherical Mirrors
- Velocity of Light
- Refraction of Light
- Refraction Through a Rectangular Glass Slab
- Refractive Index
- Refraction by Spherical Lenses
- Convex Lens
- Concave Lens
- Convex Lens
- Concave Lens
- Sign Convention for Spherical Lenses
- Magnification of a Lens
- Power of a Lens
- Human Eye: Structure of the Eye
- Eye Defect and Its Correction: Myopia Or Near-sightedness
- Applications of Spherical Mirrors and Lenses
- Dispersion by a Prism
- Atmospheric Refraction
- Some Natural Phenomena Due to Sunlight
Effects of Current
Magnetic Effects of Current
- Magnetic Effect of Electric Current
- Magnetic Field Lines
- Magnetic Force
- The Bar Magnet
- Magnetic Field Due to a Current carrying Straight Conductor
- Right-Hand Thumb Rule
- Magnetic Field Due to a Current Through a Circular Loop
- Magnetic Field Due to a Current in a Solenoid
- Force on a Current Carrying Conductor in a Magnetic Field
- Fleming’s Left Hand Rule
- Electric Motor
- Electromagnetic Induction
- Alternating Current (A.C.) Generator
- Domestic Electric Circuits
- Types of current: Alternating Current (A.C.) and Direct Current (D.C.)
- Introduction of Magnetism
Effects of Current
Natural Resources
Management of Natural Resources
- Conservation and Judicious Use of Natural Resources
- Need to Manage Our Resources
- Forests and Wild Life - Stakeholders
- Forests and Wild Life - Sustainable Management
- Coal and Petroleum
- Water for All - Dams
- Water for All - Water Harvesting
- Overview of Natural Resource Management
- Sustainability of Natural Resources
- Fresh Water Management
Our Environment
Sources of Energy
- Sources of Energy Introduction
- Good Source of Energy
- Different Forms of Energy
- Conventional Sources of Energy
- Heat Energy (Thermal Energy)
- Hydroelectric Energy
- Improvements in the Technology for Using Conventional Sources of Energy
- Solar Energy
- Alternative or Non-conventional Sources of Energy - Energy from the Sea
- Alternative Or Non-conventional Sources of Energy - Geothermal Energy
- Nuclear Energy
- Environmental Consequences
- Energy Source - How Long Will Last Us
- Renewable and Non-renewable Energy Resources
notes
The Coordination in animals is controlled by the Nervous system.
Nervous system:-
It is the network of nerve cells and fibres which transfers information via electrical impulses from one part of the body to other parts of the body. The structural and functional unit of the nervous system is the neuron and it includes:
Human Nervous System: The nervous system in humans can be divided into three main parts
1. Central Nervous System: The central nervous system is composed of the brain and the spinal cord. The brain controls all the functions in the human body. The spinal cord works as the relay channel for signals between the brain and the peripheral nervous system.
2. Peripheral Nervous System: The peripheral nervous system is composed of the cranial nerves and spinal nerves. There are 12 pairs of cranial nerves. The cranial nerves come our of the brain and go to the organs in the head region. There are 31 pairs of spinal nerves. The spinal nerves come out of the spinal cord and go to the organs which are below the head region.
3. Autonomous Nervous System: The autonomous nervous system is composed of a chain of nerve ganglion which runs along the spinal cord. It controls all the involuntary actions in the human body. The autonomous nervous system can be divided into two parts :
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Sympathetic nervous system.
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Parasympathetic nervous system.
Sympathetic Nervous System: This part of the autonomous nervous system heightens the activity of an organ as per the need. For example, during running, there is an increased demand for oxygen by the body. This is fulfilled by an increased breathing rate and increased heart rate. The sympathetic nervous system works to increase the breathing rate the heart rate, in this case.
Parasympathetic Nervous System: This part of the autonomous nervous system slows the down the activity of an organ and thus has a calming effect. During sleep, the breathing rate slows down and so does the heart rate. This is facilitated by the parasympathetic nervous system. It can be said that the parasympathetic nervous system helps in the conservation of energy.
Functions of the nervous system
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Nervous system receives information from the environment.
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To receive the information from the various body.
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To act according to through muscles and glands.
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A neuron is the structural and functional unit of the nervous system.
Neuron:
Neuron is a highly specialized cell which is responsible for the transmission of nerve impulses. The neuron consists of the following parts
(i) Cyton or cell body: The cell body or cyton is somewhat star-shaped, with many hair like structures protruding out of the margin. These hair-like structures are called dendrites. Dendrites receive the nerve impulses.
(ii) Axon: This is the tail of the neuron. It ends in several hair-like structures, called axon terminals. The axon terminals relay nerve impulses.
(iii) Myelin sheath: There is an insulator cover around the axon. This is called myelin sheath. The myelin sheath insulates the axon against nerve impulse from the surroundings.
Types of Neuron
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Sensory neuron: These neurons receive signals from a sense organ.
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Motor neuron: These neurons send signals to a muscle or a gland.
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Association or relay neuron: These neurons relay the signals between sensory neuron and motor neuron.
Synapse: The point contact between the terminal branches of axon of one neuron with the dendrite of another neuron is called synapse.
Neuromuscular Junction: It is the point where a muscle fibre comes in contact with a motor neuron carrying nerve impulse from the control nervous system.
Transmission of nerve impulse: Nerve impulses travel in the following manner from one neutron to the next: Dendrites → cell body → axon → nerve endings at the tip of axon → synapse → dendrite of next neuron.
Chemical released from axon tip of one neuron, cross the synapse or neuromuscular junction to reach the next cell.
Receptors: Receptors are the specialized tips of the nerve fibres that collect the information to be conducted by the nerves.
Receptors are in the sense organs of the animals.
These are classified as follows :
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Phono-receptors: These are present in inner ear.
Functions: The main functions are hearing and balance of the body. -
Photo-receptors: These are present in the eye.
Function: These are responsible for visual stimulus. -
Thermo-receptors: These are present in skin.
Functions: These receptors are responsible for pain, touch and heat stimuli.
These receptors are also known as thermo-receptors. -
Olfactory-receptors: These are present in nose.
Functions: These receptors receive smell. -
Gustatory-receptors: These are present in the tongue.
Functions: These helps in taste detection.
Endocrine system:-
It is a series of endocrine glands and the hormones. The endocrine glands are the ductless glands which secrete the hormones directly into the bloodstream.
Hormones are the chemical messengers mainly composed of protein which assist the nervous system in control and coordination. The pituitary gland, Thyroid Gland, Adrenal gland Pancreas, Testis, and Ovary are the different glands of the Endocrine system.