PRINCIPLES OF INHERITANCE AND VARIATIONS in 3 Hours | BEST for Class 12 Boards

NCERT Wallah・2 minutes read

Genetics deals with inheritance and variation, focusing on traits controlled by discrete units that do not blend. The text discusses complex genetic concepts, including factors, inheritance patterns, and genetic disorders, emphasizing the significance of understanding genetic expression and inheritance for predicting traits and conditions.

Insights

Genetics focuses on the principles of inheritance and variation, involving the transfer of characteristics from parents to offspring without blending, ensuring individuality.
Mendel's hybridization experiments with purebred parents led to distinct F1 and F2 generations showcasing characteristic inheritance patterns.
The text delves into complex genetic concepts, including the impact of mutations, enzymes, and alleles on genetic traits, emphasizing the importance of understanding genetic disorders like color blindness and hemophilia for informed decision-making.

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What is genetics?
The branch dealing with inheritance and variation.

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Summary

00:00

Genetics: Inheritance, Variation, and Mendel's Experiments

Genetics is a branch dealing with principal of Inheritance and variation.
Heredity involves the transfer of characteristics from parents to progeny.
Inheritance should not be transferred through a process.
Genetics deals with additive and variation aspects.
Variation refers to the amount and degree of difference between parents and progeny.
Mendel conducted the hybrid digestion experiment on plants.
Mendel selected pure parents for the experiment.
The F1 generation showed a match in characteristics from both parents.
The F2 generation exhibited a complete reassembly of characteristics from both parents.
Factors in genetics control traits as discrete units that do not blend, maintaining individuality.

18:05

Genetic Inheritance: Factors, Dominance, and Analysis

The text discusses the concept of lock dominance and loss of aggregation in inheritance, emphasizing the presence of two factors in one lodge of the division.
It mentions the dominance of a Lord of Creation and the repeat of Ek Mishra's Good Morning Everyone.
Factors present in Paris and sexual reproduction in flowering plants are highlighted.
The text revises the plant where children are joined by laddu and delves into the study of the principal of ingredients.
It discusses the molecular aspect and the significance of factors related to the control unit.
The text explores the meaning of decimals and the significance of log control unit subscription.
It emphasizes the importance of capital factors and the implications of their blending in inheritance.
The text explains the 50% chance of inheritance from parents and the concept of individuality creation through factor mix.
It details the process of test cross to determine unknown genotypes and the significance of phenotypic outcomes.
The text concludes with a focus on understanding and solving complex genetic questions through careful preparation and analysis.

38:16

Understanding Genetics: Genotypes, Phenotypes, and Dominance

Methods need to be discussed further with the elder son before teaching about Khadda A hybrid cross Dance.
Check the debit card and cigarette before frying.
Hybrid cross involves considering two characters connecting with life.
The destruction of eyes by a planet is mentioned.
Devi will erase capital and gravity, affecting the government.
Four debits will be made, with the games written down.
Pollen grains are crucial in the process.
Genotypes and phenotypes are significant in determining outcomes.
Different types of genotypes and phenotypes are explored.
Dominance and incomplete dominance are explained, with examples provided.

01:01:11

Genetic Inheritance: Traits, Alleles, Mutations, Enzymes

The text discusses the process of genetic inheritance and the generation of traits.
It mentions the importance of observing specific characteristics and patterns in the genetic makeup.
Instructions are given on how to identify different traits based on capital and small letters.
The text delves into the concept of alleles and their impact on genetic expression.
It explains the significance of mutations and their effects on genetic traits.
The text highlights the role of enzymes in genetic expression and the impact of modifications.
It emphasizes the distinction between dominant and recessive alleles in genetic inheritance.
The text provides examples of genetic traits and blood group inheritance.
It discusses the concept of multiple alleles and their influence on genetic expression.
The text concludes with a focus on the effects of gene deficiencies and their impact on metabolic pathways.

01:23:26

Genetic inheritance: complexities and implications

Phenyl pyruvic acid converts into ketone bodies, leading to their presence in urine if not reabsorbed by the kidneys.
Symptoms of mental retardation can manifest due to this process affecting various systems in the body.
Decreases in skin and hair pigmentation can occur as a result of this genetic condition.
The example of phenylketonuria highlights the impact of a recessive gene on enzyme function.
Inheritance patterns, such as incomplete dominance, play a role in determining traits like seed shape and size.
Polygenic inheritance involves multiple genes controlling a single trait, leading to variations in characteristics like eye color.
Quantity inheritance refers to the dominance of certain genes contributing to the expression of specific traits.
Chromosomal theft and polytechnic inheritance involve the control of multiple traits by more than one gene.
The concept of quantitative inheritance emphasizes the influence of dominant genes on the expression of certain traits.
Understanding the complexities of genetic inheritance, including polytechnic and quantitative aspects, is crucial for comprehending the inheritance of various traits.

01:48:09

Inheritance Theory: Linkage and Independence Explained

The theory of inheritance was first published in a village, focusing on the physical basis of inheritance.
Mandal introduced the factor 'Quit' and discussed discrete units and mixing in characters.
The factory's discreet unit was emphasized by Mandal, using maps and sets not favored by scientists at the time.
The work was published in 1965, with results in 9930 school, detailing chromosome behavior and factors.
Chromosomes and factors were compared, with legs representing independence and aggregation.
Independence in chromosomes was explained through capital and small letters, showing linkage and independence.
Experimental verification of the chromosomal theory was conducted by T.S. Maurya, showing the importance of linkage.
The concept of linkage on the same chromosome was detailed, affecting combinations and independence.
Different chromosomes signify independence, while linkage on the same chromosome indicates non-independent assortment.
Understanding the logic of linkage on the same chromosome is crucial for comprehending combinations and independence.

02:10:11

Chromosome Genes: Combinations, Linkage, and Independence

Genes on the same chromosome can lead to new combinations and prevent independent assortment.
Different chromosomes would result in different combinations and independence.
The Independence Department would exhibit various combinations.
Linkage is crucial to understand, requiring a minimum hybrid class to comprehend.
Linkage is indicated by the presence of a scent and is essential for understanding genetics.
Recombinant genes are formed through crossing over, affecting the balance of parental and recombinant types.
The distance between genes on a chromosome influences the likelihood of crossing over.
Crossing over creates new combinations and reduces linkage.
Morgan's scale quantifies the percentage of recombinant genes and the likelihood of crossing over.
Drosophila experiments demonstrate how genes on the same chromosome can lead to specific traits and combinations.

02:35:39

Genetic Inheritance and Crossbreeding Essentials

Ritesh Female is to be written, focusing on recessive female.
W and Hum, K W and Family are mentioned for cross-referencing.
W stands for Vitamin A, Vitamin A, and Be me redmi normal ring.
Reference to NCERT for those who became second class.
Discussion on X chromosome in fund generation and F1 generation.
Explanation on body color, eye color, and genetic dominance.
Emphasis on the importance of distance and light in genetic crossbreeding.
Instructions to cross two characters at least 1 hour before.
Details on the percentage of genetic recombinant and its significance.
Explanation on the process of sex determination and genetic inheritance.

02:56:55

Genetic Impact: Male and Female Dominance

Affected individuals receive a bull in the mail, with subsequent bulls sent if the initial mail icon is affected.
The text discusses the impact of male and female genetics on the mail and the factory, emphasizing the importance of identifying affected individuals.
Instructions are given to make Kadhi and solve genetic puzzles, with references to male and female dominance in pedigrees.
The text delves into the significance of identifying affected individuals in pedigrees and the potential for chandelier dominance.
It highlights the creation of pedigrees with normal and affected individuals, focusing on genetic observations and the formation of normal offspring.
The text explores genetic disorders, including sickle cell anemia, thalassemia, and color blindness, detailing the genetic mutations and their effects.
Practical advice is provided on identifying genetic disorders, understanding hemoglobin synthesis, and distinguishing between red and green colors.
The text emphasizes the role of X chromosomes in color blindness, particularly in females, and the genetic requirements for color blindness to manifest.
It discusses the prevalence of color blindness in males and females, with a focus on the genetic factors influencing the condition.
The text concludes with a reference to NCRT guidelines on female color blindness and the genetic implications of the condition.

03:18:54

Genetic Inheritance Patterns in Genetic Disorders

To determine the gender of a child with color blindness, the father must be affected by the condition, while the mother must be at least a carrier for the child to inherit the trait.
Hemophilia, a disorder affecting blood clotting, is caused by a deficiency in factor thirteen, leading to prolonged clotting times and potential clotting issues.
Hemophilia is linked to Queen Victoria's lineage, where her carrier status passed on to her descendants, affecting males more severely than females due to the genetic inheritance pattern.
Down syndrome, characterized by an extra chromosome, presents symptoms like an open mouth, low IQ, and distinct physical features, with the diagnosis based on genetic testing and chromosomal analysis.

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