Topics
Sexual Reproduction in Flowering Plants
- Flower - a Fascinating Organ of Angiosperms
- Parts of Flower
- Accessory Organs
- Essential Parts of Flower: Androecium
- Essential Parts of Flower: Gynoecium
- Pre-fertilisation in Flowering Plant: Structures and Events
- Development of Anther
- Transverse Section of Mature Anther (Microsporangium)
- Microsporogenesis
- Microspores and Pollen Grains
- Development of Male Gametophyte
- Advantages and Disadvantages of Pollen Grains
- Structure of Ovule (Megasporangium)
- Types of Ovules
- Megasporogenesis
- Development of Female Gametophyte or Embryo Sac
- Pollination
- Outbreeding Devices
- Artificial Hybridization
- Kinds of Pollination
- Self Pollination (Autogamy)
- Cross Pollination
- Agents of Pollination
- Abiotic Agents
- Biotic Agents
- Fertilization Process
- Fertilization Process
- Post Fertilisation in Plant: Structures and Events
- Development of Endosperm
- Post Fertilization in Plant: Development of Embryo (Embryogeny)
- Development of Seed
- Development of Fruit
- Apomixis
- Polyembryony
Reproduction in Organisms
- Life Span of Organisms
- Maximum Life Span of Organisms
- Reproduction in Organisms
- Types of Reproduction
- Natural Vegetative Reproduction
- Artificial Vegetative Reproduction
- Artificial Vegetative Reproduction
- Artificial Vegetative Reproduction
- Sporulation (Sporogenesis)
- Different Phases in Sexual Reproduction
- Pre-fertilisation Events in Organisms
- Fertilisation in Organisms
- Post-fertilisation Events in Organisms
Reproduction
Genetics and Evolution
Human Reproduction
- Human Reproduction
- Spermatogenesis
- Oogenesis
- Menstrual Hygiene
- Fertilization and Implantation
- Pregnancy and Embryonic Development
- Parturition and Lactation
- Embryo Development Upto Blastocyst Formation
Reproductive Health
Biology and Human Welfare
Environmental Issues
- Environmental Issues
- Prevention of Air Pollution
- Controlling Vehicular Air Pollution: a Case Study of Delhi
- Introduction of Water Pollution and Its Control
- Effects of Domestic Sewage and Industrial Effluents on Water
- A Case Study of Integrated Waste Water Treatment
- Solid Wastes
- Agrochemicals and Their Effects
- Radioactive Wastes
- Greenhouse Effect and Climate Change
- Ozone Depletion in the Stratosphere
- Degradation by Improper Resource Utilisation and Maintenance
- Deforestation and Its Causes
- Radioactive Waste Management and E-waste
- Solid Waste Management
- Noise Pollution
- Environmental Issues
Biotechnology
Principles of Inheritance and Variation
- Introduction of Principles of Inheritance and Variation
- Mendelism
- Terminology Related to Mendelism
- Mendel’s experiments on pea plant
- Monohybrid Cross
- Gregor Johann Mendel – Father of Genetics
- Punnett Square
- Back Cross and Test Cross
- Mendelian Inheritance - Mendel’s Law of Heredity
- The Law of Dominance
- The Law of Segregation (Law of Purity of Gametes)
- The Law of Independent Assortment
- Intragenic Interactions - Incomplete Dominance
- Intragenic Interactions - Codominance
- Gregor Johann Mendel – Father of Genetics
- Extensions of Mendelian Genetics (Deviation from Mendelism)
- Intragenic Interactions - Incomplete Dominance
- Intragenic Interactions - Dominance
- Intragenic Interactions - Codominance
- Multiple Alleles
- Intragenic Interactions - Pleiotropy
- Polygenic Inheritance
- Chromosomal Theory of Inheritance
- Historical Development of Chromosome Theory
- Comparison Between Gene and Chromosome Behaviour
- Chromosomal Theory of Inheritance: Law of Segregation
- Chromosomal Theory of Inheritance: Law of Independent Assortment
- Linkage and Recombination
- Sex Determination
- Sex Determination in Some Insects
- Sex Determination in Human
- Sex Determination in Birds
- Sex Determination in Honey Bees
- Pedigree Analysis
- Genetic Disorders
- Mendelian Genetics
- Chromosomal Abnormalities
- Heredity and Variation
- Linkage and Crossing Over
- Principles of Inheritance and Variation Question
Molecular Basis of Inheritance
- Introduction of Molecular Basis of Inheritance
- Deoxyribonucleic Acid (DNA) and Its Structure
- Structure of Polynucleotide Chain
- Packaging of DNA Helix
- Search for Genetic Material
- Introduction of Search for Genetic Material
- The Genetic Material is a DNA
- Properties of Genetic Material (DNA Versus RNA)
- The RNA World
- DNA Replication
- The Experimental Proof
- The Machinery and the Enzymes
- Transcription Unit
- Transcription Unit and the Gene
- Types of RNA and the Process of Transcription
- Genetic Code
- Genetic Code
- Genetic Code
- tRNA – the Adapter Molecule
- Translation
- Regulation of Gene Expression
- Operon Concept
- Human Genome Project
- DNA Fingerprinting Technique
- Structure of DNA and RNA
- Structure of Nucleotide
- Rice Genome Project
- Molecular Basis of Inheritance (Questions)
Ecology
Evolution
- Origin and Evolution of Universe and Earth
- Theories of Origin of Life
- Evolution of Life Forms - a Theory
- Theories of Biological Evolution
- Adaptive Radiation
- Organic Evolution
- Hardy Weinberg’s Principle
- Brief Account of Evolution
- Human Evolution
- Micro and Macro Evolution
- Evolution Stages
- Modern Synthetic Theory of Evolution
- Gene Flow and Genetic Drift
- Evolution
Human Health and Diseases
- Introduction of Human Health and Diseases
- Common Diseases in Human Beings
- Immunity
- Types of Immunity
- Vaccination and Immunization
- Allergies (Hypersensitivity)
- Autoimmunity
- Human Immune System
- Sexually Transmitted Diseases (STD)
- Cancer
- Introduction of Drugs and Alcohol Abuse
- Drugs and Alcohol Abuse
- Adolescence - Drug and Alcohol Abuse
- Addiction and Dependence
- Effects of Drug and Alcohol
- Prevention and Control of Drugs and Alcohol Abuse
- Infectious and Non Infectious Disease
- Maintaining Good Health, Yoga, Excercise
- Human Health and Diseases (Questions)
Strategies for Enhancement in Food Production
Microbes in Human Welfare
- Microbes in Human Welfare
- Microbes in Household Products
- Microbes in Industrial Production
- Microbes in Sewage Treatment
- Microbes in Production of Biogas
- Microbes as Biocontrol Agents
- Microbes as Biofertilizers
- Energy Generation
- Production and Judicious Use
- Microbes in Human Welfare
Biotechnology - Principles and Processes
- Process and Principles of Biotechnology
- Restriction Enzymes
- Cloning Vectors
- Competent Host (For Transformation with Recombinant DNA)
- Processes of Recombinant DNA Technology
Biotechnology and Its Application
Organisms and Populations
- Introduction of Organisms and Populations
- Ecology (Organism, Population, Community and Biome)
- Introduction of Organisms and Environment
- Major Abiotic Factors
- Responses to Abiotic Factors
- Population Attributes
- Population Growth
- Life History Variation
- Population Interactions
- Population and Ecological Adaptations
- Organisms and Populations (Questions)
Ecosystem
- Ecosystem
- Introduction and Types of Ecosystem
- Structure and Function of an Ecosystem
- Productivity
- Decomposition
- Concept of Energy Flow in an Ecosystem
- Ecological Pyramids
- Ecological Succession
- Nutrient Cycles
- Ecosystem Services
- Ecosystems Patterns
Biodiversity and Its Conservation
- Biodiversity
- Species on Earth and Species in India
- Patterns of Biodiversity
- Importance of Species Diversity to the Ecosystem
- Loss of Biodiversity
- Conservation of Biodiversity
- Endangered Organisms
- Importance of Biodiversity
- Extinction
- Red Data Book
- Biodiversity and Its Conservation (Questions)
Notes
Linkage and Recombination:
Term linkage was given by. T.H. Morgan (Father of Experimental Genetics). T.H. Morgan conducted different experiments to understand the process of linkage and recombination. He carried out several dihybrid crosses in Drosophila to study genes that were sex-linked. For example, Morgan hybridized yellow-bodied, White-eyed females to brown-bodied, red-eyed males and intercrossed those F1 progeny. He observed that the two genes did not segregate independently of each other and the F2 ratio deviated very significantly from the 9:3:3:1 ratio (expected when the two genes are independent).
- Linkage: Physical association of genes on a chromosome.
- Recombination: Generation of non-parental gene combinations.
- According to Morgan: In the same chromosome, genes which are tightly linked will show very low recombination, i.e., variation and vice-versa.
- Alfred Sturtevant used the frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes and mapped their position on the chromosome.
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