Month: September 2020

What Are Gibberellins? Discuss the functions of Gibberellins in the plant body?

Gibberellins: The term Gibberellin was given by Yabuta, 1935. They are weakly acidic plant growth hormones that possess gibbane ring structure and are able to bring about cell elongation of both leaves and stems in general and internodal length of genetically dwarf plants in particular like corn, pea, etc. The gibberellins were by chance discovered

What Are Plant Auxins? Discuss the role of Auxins (IAA) in the plant body?

Plant Auxins: Auxins are weakly acidic phytohormones with an unsaturated ring structure. They act as growth promoter hormones and help in the elongation of shoot cells. Auxin was the first hormone to be discovered. Auxins were discovered by Dutch botanist F.W.Went (1928) by experimenting on oat (Avena sativa). The chemical which works as auxin is

Plant Movements

Plant Movements: The movements in plants are not as clear as they are found in animals. But plants also show the following types of movements- Locomotory Movements: It is the type of movement in which an organism moves from one place to another. The plant’s example- Chlamydomonas shows locomotory movements with the help of flagella.

Climates of the World

Climates of the World: Hot-Wet Equatorial Climate: It is characterized by rainfall throughout the year and the temperature never goes beyond 25-27 0C and is a climate with a minimum temperature range. Hot and wet throughout the year. Also called Equatorial Rainforest Climate. Here the vegetation is hardwood type and that why it is called

Microevolution

What is Microevolution? The evolution, which results from the interaction of the elemental forces of evolution (i.e. mutation, variations, recombination, natural selection, and the genetic drift) to produce relatively small changes in the population or populations is known as microevolution. The basic process of microevolution consists of a change in the gene frequencies in a

American Revolution or American War of Independence

What is the American Revolution? The Europeans began to make settlements in America in the sixteenth century. Earlier, Christopher Columbus had discovered America in 1492. Amerigo Vespucci made four voyages to  America and gave a vivid description of the land. After these voyages, there was a substantial migration of people from Britain and France to

Difference between Lamarckism and Darwinism

Difference between Lamarckism and Darwinism: Charles Darwin in his book ‘The Origin of Species‘ or the preservation of favored races in the struggle For life (1859) proposed that there is inherited variation (polymorphism) in populations of animals and plants, more creatures are born than can survive (a struggle for existence), and individuals carrying certain favorable

Darwinism or Theory of Natural Selection

Darwinism: Charles Darwin, the author of the book ‘The Origin of Species‘ or the preservation of favoured races in the struggle For life (1859), has been credited with for giving the first systematic as well as the comprehensive approach in the perspective of evolutionary development. His theory is commonly known as Darwinism. In his book