Human Reproduction :- Human beings are nonseasonal breeders ,there is no Oestrus / heat . Male Reproductive System :- In human reproduction , The male Reproductive System Consists of paired testes , Several Accessory glands , a duct System and a mating Organ called the penis . Scrotum :- In man , both testes normally…
Development of Embryo in Flowering Plants :- Development of Embryo in Flowering Plants occur at the micropylar end of the embryo sac where the zygote is situated . Endosperm :- During the development of Embryo in Flowering Plants the primary endosperm cell divides repeatedly and form a triploid Endosperm tissue .The cells of this tissue…
Structure of Flower :- A Flower is the Sexual Reproductive Organ in Plants. Flowers are often the most attractive structures of plant. Calyx :- These are green Petal like structure that are found in right above the base of the flower called Receptacles. Corolla :- It is the collective name given to the petals which…
Sexual Reproduction :- Sexual reproduction occurs when the sperm from the male parent fertilizes an egg from the female parent, producing an offspring that is genetically different from their parents. The Stages of Sexual Reproduction :- 1. Pre – fertilization :- This stage involves the events prior to fertilization. Gamete formation ( Gametogenesis ) and…
Reproduction :- Reproduction is the biological process by which new individual organisms ( offsprings ) are produced from their parents. It is a fundamental features of all known life. Types of Reproduction :- There are of mainly two types. – Asexual Reproduction :- It is the biological process in which an organism can reproduce without…
Magnetic properties of Crystals :- Each electron in an atom behaves like a magnet. It’s magnetic moment originates from two types of motions are orbital motion around the nucleus and spin around its own axis. Magnitude of magnetic moment is very small and is measured in the unit called Bohr magneton μB. It is equal…
Conductors:- The solids with conductivities ranging between 10⁴ to 10⁷ ohm⁻¹ m⁻¹ are called conductors. Examples. – Metals like Iron, Copper, Sodium etc. Insulators :- Semiconductors :- These are the solids with conductivities in the intermediate range from 10⁻⁶ to 10⁴ ohm⁻¹ m⁻¹· Examples. – Silicon and Germenium shows this behaviour called intrinsic semiconductor. Types…
A solid consists of an aggregation of large number of small crystals, these small crystals have defects in them which are called defects in crystals. The defects in crystals are basically irregularities in the arrangement of constituent particles. Types of defects in crystals :- The defects in crystals are of mainly two types:- ( a…
Atomic radius :- Thus, the edge length or side of the cube a and the atomic radius of each particle r are related as a = 2 r r = a / 2 In ∆ EFD, b² = a² + a² = 2a b = √2 a Now in ∆ AFD c² = a² +…
In Crystals, the constituent particles are close packed and leaving the minimum vacant space. In such a situation, the entropy of crystalline material becomes minimum. Let us consider the constituent particles as identical hard spheres and build up three dimensional structure in following three steps – Close Packing in one Dimension :- There is only…
W. H. Miller in 1839 represented the planes of a crystal by a set of three integers h, k and l, called the Miller indices. To obtained the Miller indices for any crystal plane, the ratios of the intercepts made by the unit plane to those made by the given plane or its parallel plane…
Theoretical Density :- Knowing the unit cell dimensions, the theoretical density d of a cubic crystal can be calculated from the equation d = Z M / N V where Z is the number of atoms in the unit cell, M is the molar mass, V is the volume of the unit cell and N…
