Reproduction in Lower and Higher Plants
- Reproduction in Plant
- Mode of Reproduction in Plant
- Asexual Reproduction in Plant
- Vegetative Reproduction
- Natural Vegetative Reproduction
- Artificial Vegetative Reproduction - Conventional Method
- Sexual Reproduction in Flowering Plants
- Pre-fertilization in Plant: Structure and Events
- Pre-fertilization in Plant: Stamen (Male Reproductive Unit)
- Pre-fertilization in Plant: Microsporangium
- Structure of Microspore Or Pollen Grain
- Pre-fertilization in Plant: Pistil (Female Reproductive Unit)
- Pre-fertilization in Plant: Megasporangium
- Pre-fertilization in Plant: Formation of Embryo Sac
- Self Pollination (Autogamy)
- Cross Pollination
- Cross Pollination
- Agents of Pollination
- Outbreeding Devices
- Pollen Pistil Interaction
- Double Fertilization and Triple Fusion in Plant
- Post Fertilisation in Plant: Structures and Events
- Development of Endosperm
- Post Fertilization in Plant: Development of Embryo (Embryogeny)
- Formation of Seed and Fruit
Reproduction in Lower and Higher Animals
- Reproduction in Animal and Human
- Mode of Reproduction in Animal
- Asexual Reproduction in Animal
- Sexual Reproduction in Animals
- Human Reproductive System
- The Male Reproductive System
- The Female Reproductive System
- Menstrual Cycle (Ovarian Cycle)
- Fertilization in Human
- Embryonic Development in Human
- Implantation in Human
- Pregnancy in Humans
- Placenta (Growth) in Human
- Parturition (Birth) in Human
- Lactation in Human
- Reproductive Health
- Population Stabilisation and Birth Control
- Medical Termination of Pregnancy (MTP)
- Sexually Transmitted Diseases (STD)
Inheritance and Variation
- Gregor Johann Mendel – Father of Genetics
- Genes and Genetic
- Mendelian Inheritance - Mendel’s Laws of Heredity
- Back Cross and Test Cross
- Deviations from Mendel’s Findings
- Chromosomal Theory of Inheritance
- Chromosomes - The Carriers of Heredity
- Linkage and Crossing Over
- Autosomal Inheritance
- Sex Linked Inheritance
- Sex Determination
- Genetic Disorders
Molecular Basis of Inheritance
Origin and Evolution of Life
- Origin and Evolution of Universe and Earth
- Theories of Origin of Life
- Chemical Evolution of Life (Self-assembly Theory of the Origin of Life)
- Darwin’s Theory of Natural Selection
- Mutation Theory
- Modern Synthetic Theory of Evolution
- Mechanism of Organic Evolution
- Hardy Weinberg’s Principle
- Adaptive Radiation
- Evidences for Biological Evolution
- Geological Time Scale
- Origin and Evolution of Man
Plant Water Relation
- Plant Water Relation
- Properties of Water
- Water and Mineral Absorption by Root
- Characteristics of Roots for Absorbing Water
- Water Available to Roots for Absorption
- Means of Transport in Plants
- Concept of Imbibition
- Simple Diffusion
- Concept of Osmosis
- Osmotic Pressure
- Facilitated Diffusion
- Turgidity and Flaccidity (Plasmolysis)
- Active Transport
- Passive Transport
- Water Potential (ψ)
- Path of Water Across the Root
- Translocation of Water (Ascent of Sap)
- Translocation of Mineral Ions
- Transport of Food
- Kinds of Transpiration
- Structure of Stomatal Apparatus
- Significance of Transpiration
Plant Growth and Mineral Nutrition
- Plant Growth
- Phases of Plant Growth
- Conditions Necessary for Plant Growth
- Plant Growth Rate
- Types of Plant Growth
- Plant Growth Curve
- Differentiation, De-differentiation, Re- Differentiation
- Plant Development
- Plant Plasticity
- Plant Hormones
- Types of Plant Hormones: Auxins
- Types of Plant Hormones: Gibberellins
- Types of Plant Hormones: Cytokinins
- Types of Plant Hormones: Ethylene
- Types of Plant Hormones: Abscisic Acid (ABA)
- Vernalization (Yarovization)
- Plant Mineral Nutrition
- Nitrogen Cycle
Respiration and Circulation
- Organs of Respiratory Exchange
- Human Respiratory System
- Breathing – Respiratory Cycle
- Regulation of Respiration
- Modified Respiratory Movements
- Disorders of Respiratory System
- Transportation in Living Organisms
- Types of Blood Circulation
- Types of Blood Circulation
- Blood Circulatory System in Human
- Composition of Blood: Plasma (The Liquid Portion of Blood)
- Composition of Blood: Red Blood Cells (Erythrocytes)
- Composition of Blood: White Blood Cells (Leukocytes)
- Composition of Blood: Blood Platelets (Thrombocytes)
- Function of Platelets - Clotting of Blood (Coagulation)
- Human Heart
- Circulation of Blood in the Heart: Cardiac Cycle
- Blood Vessels – Arteries, Veins, and Capillaries
- Blood Pressure (B.P.)
- Electrocardiogram (ECG)
- Lymph and Lymphatic System
Control and Co-ordination
- Control and Co-ordination
- Nervous System in Hydra
- Nervous System in Planaria (Flatworm)
- Neural Tissue
- Neuron (Or Nerve Cell) and Its Types
- Neuroglial Cells (Or Glial Cells)
- Neuron as Structural and Functional Unit of Neural System
- Nerve Fibres
- Transmission of Nerve Impulse
- Human Nervous System
- Central Nervous System (CNS)
- The Human Brain
- Central Nervous System (CNS): Structure of Human Brain
- The Spinal Cord
- Reflex and Reflex Action
- Reflex Arc
- Peripheral Nervous System (PNS)
- Sensory Receptors
- Human Eye: Structure of the Eye
- Working of the Human Eye
- Human Ear
- Disorders of Nervous System
- Human Endocrine System
- The Hypothalamus
- Pituitary Gland or Hypophysis Gland
- The Pineal Gland
- Thyroid Gland
- Parathyroid Gland
- Thymus Gland
- Adrenal Gland (Suprarenal Gland)
- Pancreas (Islets of Langerhans)
- Reproductive Glands (Gonads)
Human Health and Diseases
- Defence System in Our Body: Immune System
- Types of Immunity
- Vaccination and Immunization
- Structure of Antibody
- Categories of Disease
- Protozoan Diseases
- Helminthic Diseases
- Bacterial Diseases
- Viral Diseases
- Fungal Diseases
- Vector Borne Diseases
- Sexually Transmitted Diseases (STD)
- Drug Abuse
Enhancement of Food Production
- Improvement in Food Production
- Plant Breeding
- Tissue Culture
- Single Cell Protein (SCP)
- Animal Husbandry (Livestock)
- Animal Breeding
- Dairy Farming
- Poultry Farming
- Apiculture (Bee Farming)
- Pisciculture (Fish Farming)
- Lac Culture
- Microbes in Human Welfare
- Microbes in Industrial Production
- Microbes in Sewage Treatment
- Microbes in Energy Generation
- Microbes as Biocontrol Agents
- Microbes as Biofertilizers
Organisms and Populations
Ecosystems and Energy Flow
Biodiversity, Conservation and Environmental Issues
- Levels of Biodiversity
- Patterns of Biodiversity
- Biodiversity Current Scenario
- Loss of Biodiversity
- Conservation of Wildlife
- Biological Diversity Act, 2002
- Environmental Issues
- Air Pollution and Its Causes
- Effects of Air Pollution
- Prevention of Air Pollution
- Noise Pollution
- Measures to Limit Noise Pollution
- Water Pollution and Its Causes
- Effects of Water Pollution
- Prevention of Water Pollution
- Green House Effect
- Preventive Measures of Green House Effect
- Global Warming
- Preventive Measures of Global Warming
- Ozone Layer Depletion
- Deforestation and Its Causes
- Mission Harit Maharashtra
Excretion and Osmoregulation
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 :
Sympathetic nervous system.
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
Nervous system receives information from the environment.
To receive the information from the various body.
To act according to through muscles and glands.
A neuron is the structural and functional unit of the nervous system.
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
Sensory neuron: These neurons receive signals from a sense organ.
Motor neuron: These neurons send signals to a muscle or a gland.
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 :
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.
- Human Nervous system
- Need of Nervous System
- Components of Nervous System
Shaalaa.com | Control & Co-ordination part 11 (Nervous System: Introduction)
Series: series 1
The life processes in humans are controlled and regulated by :
(a) reproductive and endocrine systems
(b) respiratory and nervous systems
(c) endocrine and digestive systems
(d) nervous and endocrine systems
What are the main organs of the human nervous system? Draw a labelled diagram to show the main organs of the human nervous system.
What is the function of receptors in our body? Think of situations where receptors do not work properly. What problems are likely to arise?
What does the central nervous system in humans consist of? What is the job of the central nervous system?