Topics
Reproduction
Biotechnology - Principles and Processes
Principles of Inheritance and Variation
- Principles of Inheritance and Variation Introduction
- Mendel’s Laws of Inheritance
- Monohybrid Cross - Inheritance of One Gene
- Law of Dominance
- Law of Segregation
- Law of Segregation - Incomplete Dominance
- Law of Segregation - Co-dominance
- Dihybrid Cross - Inheritance Two Genes and Law of Independent Assortment
- Mendel’s Laws of Inheritance
- Chromosomal Theory of Inheritance
- Linkage and Crossing Over
- Introduction of Sex Determination
- Sex Determination
- Concept of Mutation
- Pedigree Analysis
- Genetic Disorders
- Genetic Disorders
- Elementary Idea of Polygenic Inheritance
- Deviations from Mendelism - Incomplete Dominance, Co-dominance, Multiple Alleles and Inheritance of Blood Groups, Pleiotropy
- Heredity and Variation
- Sex Determination in Birds
- Sex Determination in Honey Bees
- Principles of Inheritance and Variation Question
Human Health and Diseases
- Introduction of Human Health and Diseases
- Common Diseases in Humans
- Immunity
- Types of Immunity: Innate or Inborn (Inherited) Immunity and Acquired or Adaptive Immunity
- Vaccination and Immunization
- Allergy
- Autoimmunity
- Immune System in the Body
- Sexually Transmitted Diseases (STD)
- Cancer
- Introduction of Drugs and Alcohol Abuse
- Adolescence - Drug and Alcohol Abuse
- Addiction and Dependence
- Effects of Drug / Alcohol Abuse
- Prevention and Control of Drugs and Alcohol Abuse
- Infectious and Non Infectious Disease
- Maintaining Good Health, Yoga, Excercise
- Human Health and Diseases (Questions)
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
- Adaptations and Its Types
- Population Attributes
- Population Growth
- Life History Variation
- Population Interactions
- Population and Ecological Adaptations
- Organisms and Populations (Questions)
Reproduction in Organisms
- Life Span of Organisms
- Maximum Life Span of Organisms
- Reproduction in Organisms
- Types of Reproduction
- Asexual Reproduction
- Asexual Reproduction in Plant
- Asexual Reproduction in Animal
- Sexual Reproduction
- Different Phases in Sexual Reproduction
- Events in Sexual Reproduction in Organisms
- Pre-fertilisation Events in Organisms
- Fertilisation in Organisms
- Post-fertilisation Events in Organisms
Biotechnology and Its Application
Strategies for Enhancement in Food Production
- Introduction of Strategies for Enhancement in Food Production
- Animal Husbandry (Livestock)
- Dairy Farming (Cattle Farming)
- Poultry Farming
- Apiculture (Bee Farming)
- Pisciculture (Fish Farming)
- Animal Breeding
- Plant Breeding
- Single Cell Protein (SCP)
- Tissue Culture
- Strategies for Enhancement in Food Production (Questions)
Ecosystem
Genetics and Evolution
Sexual Reproduction in Flowering Plants
- Flower - a Fascinating Organ of Angiosperms
- Sexual Reproduction in Flowering Plants
- Androecium: Male Reproductive Organ
- Gynoecium: Female Reproductive Organ
- Pollination
- Kinds of Pollination
- Agents of Pollination
- Outbreeding Devices
- Pollen Pistil Interaction
- Artificial Hybridization
- Double Fertilization in Plants
- Development of Endosperm
- Development of Embryo
- Seed from Ovule
- Fruit from Ovary
- Polyembryony
Molecular Basis of Inheritance
- Introduction of Molecular Basis of Inheritance
- Structure of Polynucleotide Chain
- Packaging of DNA Helix
- Introduction of Search for Genetic Material
- The Genetic Material is a DNA
- Properties of Genetic Material (DNA Versus RNA)
- Concept of RNA World
- The Experimental Proof
- The Machinery and the Enzymes
- Introduction of Transcription
- Transcription Unit
- Transcription Unit and the Gene
- Types of RNA and the Process of Transcription
- Introduction of Genetic Code
- Mutations and Genetic Code
- tRNA – the Adapter Molecule
- Concept of Translation
- Introduction of Regulation of Gene Expression
- The Lac Operon
- Human Genome Project
- DNA Fingerprinting Technique
- Structure of DNA and RNA
- Structure of Nucleotide
- Rice Genome Project
- Molecular Basis of Inheritance (Questions)
Human Reproduction
- Human Reproduction Introduction
- Male Reproductive System
- Female Reproductive System
- Gametogenesis in Animal
- Menstrual Cycle (Ovarian Cycle)
- Fertilisation and Implantation
- Pregnancy and Embryonic Development
- Parturition and Lactation
- Microscopic Anatomy of Testis
- Microscopic Anatomy of Ovary
- Embryo Development Upto Blastocyst Formation
- Human Reproduction Questions
Evolution
- Origin and Evolution of Universe and Earth
- Origin of Life (Theories)
- Evolution of Life Forms - a Theory
- Evidence of Organic Evolution
- Adaptive Radiation
- Biological Evolution
- Mechanism of Organic Evolution
- Hardy Weinberg’s Principle
- Brief Account of Evolution
- Human Evolution
- Theories of Evolution: Darwinism or Theory of Natural Selection
- Micro and Macro Evolution
- Speciation
- Evolution Stages
- Modern Synthetic Theory of Evolution
- Gene Flow and Genetic Drift
- Evolution (Questions)
Microbes in Human Welfare
Biodiversity and Its Conservation
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
- Domestic Sewage and Industrial Effluents
- A Case Study of Integrated Waste Water Treatment
- Concept of 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 and Its Applications
Reproductive Health
Ecology and Environment
description
- Flower - a fascinating organ of angiosperms
- A diagrammatic representation of the flower
- Parts of a flower
- Life span of flower
notes
Flower - a fascinating organ of angiosperms:
- The reproduction process takes place in the plant via a special structure known as the flower.
- Flowers are morphological and embryological marvels.
- The floral primordium undergoes hormonal and structural changes to form flowers.
- Flowers can either be
- Complete Flower - A complete flower is one that has a calyx of sepals, a corolla of petals, an androecium of stamens, and a gynoecium of carpels (pistil).
- Incomplete Flower - An incomplete flower is defined as a flower missing any of its main parts in its natural form, i.e., petals, sepals, stamens or pistils.
- A complete flower consists of two different parts: the vegetative part and the reproduction part.
notes
Flower – Diagram:
A diagrammatic representation of the lateral side (L.S.) of a flower |
notes
Parts of a flower:
The different parts of a flower are mentioned below:
A) Vegetative part of a flower:
The vegetative part of a flower consists of the calyx and corolla. The calyx and corolla are referred to as accessory whorls of the flower because they do not participate in the reproduction process but rather help it.
- Calyx - It is the outermost whorl of a flower. It consists of sepals, which are tiny green-coloured parts at the base of the flower. It protects the flower from any sort of mechanical injuries and desiccation. Some plants have coloured sepals the calyx are called petaloid. In many flowers, the sepals drop off at an early stage of development (i.e., before the flower even opens fully), they are known as caducous. Deciduous are the sepals that drop off after fertilization. The persistent sepals remain up to the fruiting stage. If the sepals are free the calyx is called polysepalous, and if they are united it is called gamosepalous.
- Corolla - It consists of petals of the flower. It is the second whorl of a flower. It attracts the pollinators which help to reproduce by transferring the pollen grain. It also protects the reproductive parts of a flower. Calyx and Corolla are collectively known as ‘perianth’.
(B) Reproductive parts of a flower:
The androecium and gynoecium are known as essential whorls because they are directly related to reproduction.
- Androecium - It is the male reproductive part of a flower, comprising stamens and it is the third main whorl of a flower. Each stamen comprises two parts, anther and filament. Anther is a bilobed (2 lobes) sac-like structure which is supported by the filament. The anther is an important part as it produces the pollen grains by performing meiosis. The filament is a long and slender stalk which is attached to the anther.
- Gynoecium - It is the female reproductive part of a flower. It is the fourth whorls of a flower situated in the central position of the thalamus. It consists of a pistil and its components are stigma, style, and ovary. The ovary is a chamber where the egg or ovule is stored for fertilization. Stigma is attached to the top of the carpel; it is the landing site of a pollen grain. Style is a tube-like structure that connects the ovary and the stigma. It transfers the pollen grain to the ovary.
notes
Life span of flower:
- Monocarpic plants: The plants in which flowering and fruiting take place only once in the whole life span are called monocarpic e.g., Annual & Biennial plants. Plants the annual and biennial types show clearcut vegetative/juvenile, reproductive and senescent phases, but in the perennial species,
- Polycarpic plants: Polycarpic plants are those that flower and fruit multiple times during their life cycle, such as perennial plants. It is very difficult to clearly define life span phases in the case of perennial species.
Exception: Monocarpic plants include bamboo, century plant (Agarerica Strothu kothiename perennial pists), and perennial pists. Bamboo species only flower once in their lives, usually after 50-100 years, produce a great number of fruits and die Strobilanthus kunthiana (Nezlakuranji) flowers only every 12 years. It flowered between September and October of 2006, transforming wide sections of hilly areas in Kerala, Karnataka, and Tamil Nadu into blue stretches and attracting a great number of tourists.
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