Blog – BSI SIR FAN CLUB

NCERT- Evolution Diagram Dinosaur -A family tree of dinosaurs and their living modern day counterpart organisms like crocodiles and birds

Evolution, NCERT LINE BY LINE / Prof. Siddharth Sanghvi

Evolutionary Lineage of Archosauria Category Description Examples Archosauria (Common Ancestor) Archosaurs, a group of reptiles from the early Triassic (~250 million years ago), are the common ancestor of crocodilians, pterosaurs, and dinosaurs. None Branches Crocodylomorpha (Crocodilians) Crocodiles and their relatives diverged early (~230 million years ago). Evolved independently but retained traits of their ancient archosaur […]

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Cytoplasmic Inheritance by Sidd Sir – Male sterility in maize, variegated leaves in Mirabilis jalapa.

NCERT LINE BY LINE, PRINCIPLES OF INHERITANCE AND VARIATION / Prof. Siddharth Sanghvi

Comparison of Cytoplasmic and Nuclear Inheritance Feature Cytoplasmic Inheritance Nuclear Inheritance Definition Transmission of traits via genes located in organelles like mitochondria or chloroplasts. Transmission of traits via genes in the nuclear chromosomes. Location of Genes Found in mitochondrial or chloroplast DNA (extranuclear). Found in chromosomal DNA inside the nucleus. Inheritance Pattern Maternal (zygote inherits

Cytoplasmic Inheritance by Sidd Sir – Male sterility in maize, variegated leaves in Mirabilis jalapa. Read More »

MOLECULAR BASIS OF INHERITANCE -1- Over the next hundred years, the nature of the putative genetic material was investigated culminating in the realisation that DNA – deoxyribonucleic acid – is the genetic material, at least for the majority of organisms.

Molecular Basis of Inheritance, NCERT LINE BY LINE / Prof. Siddharth Sanghvi

Master Table: Molecular Basis of Inheritance Topic Explanation Key Details MCQ Inheritance Patterns Factors regulating inheritance patterns were unclear in Mendel’s time but are now linked to genetic material (DNA/RNA). – DNA is the genetic material in most organisms.– RNA functions as a genetic material in some viruses and a messenger in others. Q: What

MOLECULAR BASIS OF INHERITANCE -1- Over the next hundred years, the nature of the putative genetic material was investigated culminating in the realisation that DNA – deoxyribonucleic acid – is the genetic material, at least for the majority of organisms. Read More »

Difference Between Progeny and Offspring in Genetics

NCERT LINE BY LINE, PRINCIPLES OF INHERITANCE AND VARIATION / Prof. Siddharth Sanghvi

Difference Between Progeny and Offspring in Genetics Aspect Progeny Offspring Definition Progeny refers to the descendants or the next generation of an organism, often used in a broader scientific or formal context. Offspring refers to the immediate biological descendants of an organism, typically used in a general or informal context. Context More commonly used in

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Five factors are known to affect Hardy-Weinberg equilibrium. These are gene migration or gene flow, genetic drift, mutation, genetic recombination and natural selection. When migration of a section of population to another place and population occurs, gene frequencieschange in the original as well as in the new population. New genes/alleles are added to the new population and these are lost from the old population.There would be a gene flow if this gene migration, happens multiple times.If the same change occurs by chance, it is called genetic drift. Sometimesthe change in allele frequency is so different in the new sample of populationthat they become a different species. The original drifted population becomes founders and the effect is called founder effect.

Evolution, NCERT LINE BY LINE / Prof. Siddharth Sanghvi

MECHANISMS OF EVOLUTION Although the term “evolution” is often used synonymously with “natural selection,” they are actually referring to different concepts. Evolution is an observable phenomenon in which gene frequencies change over time, but it does not explain why a population is undergoing evolution. This is where natural selection—and other mechanisms—come into play. They explain

Five factors are known to affect Hardy-Weinberg equilibrium. These are gene migration or gene flow, genetic drift, mutation, genetic recombination and natural selection. When migration of a section of population to another place and population occurs, gene frequencieschange in the original as well as in the new population. New genes/alleles are added to the new population and these are lost from the old population.There would be a gene flow if this gene migration, happens multiple times.If the same change occurs by chance, it is called genetic drift. Sometimesthe change in allele frequency is so different in the new sample of populationthat they become a different species. The original drifted population becomes founders and the effect is called founder effect. Read More »

Cleistogamy is a highly advantageous strategy in stable or harsh environments, where ensuring reproduction outweighs the need for genetic diversity. However, it is often complemented by chasmogamous flowers in plants that balance the need for self-pollination with opportunities for cross-pollination, allowing them to enjoy the benefits of both strategies.

NCERT LINE BY LINE, Sexual Reproduction in flowering Plants / Prof. Siddharth Sanghvi

Cleistogamous Flowers: Benefits and Features Aspect Description Protection Cleistogamous flowers near the soil level are protected from harsh environmental conditions like wind, rain, and excessive heat. Self-pollination Efficiency Being close to the ground minimizes disturbances, making the self-pollination process efficient. Energy Conservation Flowers save energy by not producing elaborate structures for pollinator attraction. Seed Dispersal

Cleistogamy is a highly advantageous strategy in stable or harsh environments, where ensuring reproduction outweighs the need for genetic diversity. However, it is often complemented by chasmogamous flowers in plants that balance the need for self-pollination with opportunities for cross-pollination, allowing them to enjoy the benefits of both strategies. Read More »

PHOTOPERIODISM and VERNALISATION

NCERT LINE BY LINE, Plant Growth and Development / Prof. Siddharth Sanghvi

Photoperiodism: Key Details Aspect Details Definition The response of plants to periods of day and night, influencing flowering based on light and dark duration. Requirement for Flowering Some plants require specific light exposure to induce flowering and can measure the duration of light exposure. Categories of Plants Long Day Plants (SNP): Require light exposure exceeding

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Interaction :Competition for NEET

NCERT LINE BY LINE, Organism and Population / Prof. Siddharth Sanghvi

Competition and Its Ecological Outcomes (STR) Topic Description Examples Introduction to Competition Competition is an ecological interaction where individuals vie for the same limited resources like food, space, light, or mates. It occurs within the same species (intraspecific) or between species (interspecific), influencing survival, adaptation, and evolution. Barnacles, Paramecium species Intraspecific Competition Occurs among individuals

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Lungs – Pulmonary Pressures and Lung Functioning for Biology Olympiad

NCERT LINE BY LINE, Respiratory System, Zoology / Prof. Siddharth Sanghvi

Short Time Reading Aspect Description Atmospheric Pressure (Patm) The pressure exerted by air weight in the atmosphere, typically around 760 mmHg at sea level. It serves as a reference for measuring other pressures in the lungs. Intrapulmonary Pressure (Ppul) Also known as alveolar pressure, it’s the pressure within lung alveoli. This pressure fluctuates above and

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Counter-Current Multiplier and Exchange

Urinary System, Zoology / Prof. Siddharth Sanghvi

Aspect Description Medullary Gradient Definition: The progressive increase in solute concentration from the cortex to the inner medulla of the kidney. Location: From outer cortex down to the inner medulla. Importance: Establishes a concentration gradient critical for water reabsorption and urine concentration, helping the kidney adjust urine concentration according to hydration needs. Countercurrent Multiplier Definition:

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