Dispersion by a prism :- When white light ( Sun light ) is incident on a glass prism, the emergent light is seen to be consisting of several colours, the phenomenon of splitting of light into several component colours is known as dispersion. The different component colours that appear in sequence are violet, indigo, blue,…
Angle of deviation ( δ ) :- The passes of light through a triangular prism ABC, The angles of incidence and refraction at the first face AB are i₁ and r₁ while the angle of incidence at the second face AC is r₂ and the angle of refraction or emergence i₂ . The angle between…
Equivalent focal length of two lenses :- Let us consider two lenses L₁ ( focal length f₁ ) and L₂ ( focal length f₂ ) are separated by a distance d and P₂ is equivalent lens of both lenses ( focal length f ). Angle of deviation produce by the lenses P, L₁ and L₂…
Let us consider two lenses A anb B of focal length f₁ and f₂ placed in contact with each other. Let the object be placed at a point O beyond the focus of the first lens A. The first lens produces an image at I₁ is real, it serves as a virtual object for the…
Refraction of light at a convex surface :- 1. For real image :- The figure shows the geometry of formation of image I of an object O on the principal axis of a spherical surface ( convex ) with centre of curvature C and radius of curvature R. The rays are incident from a medium…
1. Incomplete dominance :- It is a post Mendelian discovery. In the case heterozygous condition of gene results in intermediate phenotype as one allele is only incompletely don’t over the other. The intermediate of flower colour in the Mirabilis jalapa is a good example to understand incomplete dominance. In a cross between true breeding red…
Mendel’s laws of inheritance :- Mendel’s present his paper on principles of heredity at the annual conventy on natural history society at Brun ( Austria ) in 1895. This paper use published in the proceeding on the conference in 1866. Tittle of this paper was experiment in plant hybridization. These principles are – 1. Law…
Monohybrid cross :- Monohybrid is the cross involves one character and single gene pair.It leads to monohybrid offspring in F₁ generation. Mendel proposed that in a true breeding, tall or dwarf pea variety the allelic pair of genes for height are identical or homozygous, TT and tt respectively. TT and tt are called genotype of…
It is a cross which involves two characters and two gene pair. it leads to dihybrid F₁ offspring. Mendel worked with and crossed pea plants that differed in two characters, as is seen in the cross between a pea plant that has seeds with yellow colour and round shape, one that had seeds of green…
Allele or Allelomorph :- Genes which code for a pair of contrasting traits are known as alleles, i.e. They are slightly different forms of the same gene. Example – In case of the character of height, T is used for the tall trait and t for the dwarf, T and t are alleles of each…
Genetics :- Genetics is the branch of biology concerned with the study of genes, genetic variation and heredity in organisms. Heredity :- It is the passing on of traits from parents to their offspring, either through asexual reproduction or sexual reproduction. The traits or characters are called hereditary characters. Gene :- A gene is the…
डीएनए (DNA) क्या है? डीएनए (Deoxyribose Nucleic Acid) न्यूक्लियोटाइड्स का एक लंबा बहुलक है जिसकी लंबाई न्यूक्लियोटाइड के संख्या पर निर्भर करती है न्यूक्लियोटाइड की संख्या अधिक होने पर डीएनए भी अधिक लंबे होते हैं। डीएनए (DNA) की संरचना :- न्यूक्लियोटाइड्स :- न्यूक्लियोटाइड के निम्नांकित तीन घटक होते हैं – नाइट्रोजन क्षारक दो प्रकार के…
