Inventors and Scientific Discoveries

Mendel was successful in formulating the laws of inheritance whereas his predecessors were not because of the following reasons.

He selected only pure breeding varieties of pea for his experiments.

He took one or two characters at one time while his predecessor often studied all the traits simultaneously.

He formulated theoretical explanations for interpreting his results.

He used statistical methods and law of probability for analyzing results, etc.,

So, the correct explanation is ‘He studied one clear-cut character at a time’.

Mendel’s work(monohybrid cross & dihybrid cross) did not receive any recognition, remained unnoticed, and unappreciated for several years due to the following reasons:

Communication was not easy in those days and his work could not be widely publicized.

His concept of stable, unblending and discrete units or factors for various traits did not find acceptance from the contemporaries.

His approach of using mathematics and statistical analysis to explain biological phenomena was totally new and unacceptable to many biologists. He could not provide any physical proof for the existence of factors. In 1900, three scientists Hugo de Vries, Carl Correns, and Erich von Tschermark, worked independently on Mendel’s work, proved whatever explained by Mendel on inheritance is true. It is called Rediscovery of Mendel’s laws.

He chose garden pea that was easy to grow and to hybridise artificailly.

The plant reproduce well and grows to maturity in a single season.

Mendel then chose to follow seven visible features(unit characters), each represented by two contrasting forms or traits.

Mendel was fortunate in choosing a diploid plant because diploid organisms contain only two sets of chromosomes.

A singe alteration in a trait was therefore demonstrated by a visible differences between varieites.

He restricted his examination to one or very few pairs of contrasting traits in each experiment.

He also kept accurate quatitative records, a necessity in genetic experiments.

In his experiments, no appearance of recombinations and linkage.

So, the correct option is ‘Traits chosed by him had genes far apart so that linkage was absent’.

Mendel’s law of inheritance were rediscovered by Hugo de vries, Tschemark, Correns. Hugo de vries republished the Mendel’s work in ‘Flora’.

So, the correct option is ‘De vries’.

Carl Erich Correns was a German botanist and geneticist, who is notable primarily for his independent discovery of the principles of heredity, and for his rediscovery of Gregor Mendel's earlier paper on that subject, which he achieved simultaneously but independently of the botanists Erich Tschermak von Seysenegg. He also converted Mendel’s conclusions into principles of heredity.

So, the conclusion is ‘Carl correns’.

Erich Tschermak was an Austrian agronomist who developed several new disease-resistant crops, including wheat-rye and oat hybrids. He independently rediscovered Gregor Mendel's work on genetics. He was a plant breeder, and his hybridization experiments were done with the idea of improving crops using the laws of heredity.

So, the correct option is ‘Austria’.

Hugo de Vries, Holland botanist and geneticist, is the author of the mutation theory of evolution. His work led to the rediscovery and establishment of Mendel's laws. He made his first notable contributions to science in the 1880s in the field of plant physiology.

So, the correct option is ‘Holland’.

Carl Erich Correns was a German botanist and geneticist, who is notable primarily for his independent discovery of the principles of heredity, and for his rediscovery of Gregor Mendel's earlier paper on that subject, which he achieved simultaneously but independently of the botanists Erich Tschermak von Seysenegg and Hugo de Vries, and the agronomist William Jasper Spillman.

So, the correct option is ‘German’.

Mendel’s laws of inheritance was rediscovered by Hugo de Vries, Carl Correns, and T.Schemark independently.

So, the correct option is ‘Von Tschemark’.

Henry Ford is famous for revolutionizing the manufacturing industry by implementing the moving assembly line for the mass production of the Model T.

Nikola Tesla is often referred to as the mad scientist of the 1900s due to his eccentric personality and his visionary, sometimes unconventional, electrical inventions.

Alfred Nobel, a Swedish chemist, invented dynamite in 1867. He later used his fortune to establish the Nobel Prizes.

H. H. Holmes is widely considered the first modern American serial killer, active during the late 19th century in Chicago. The other options are fictional characters or inventors.

Guglielmo Marconi is credited with the invention and patenting of the radio, building on the work of earlier scientists like Hertz and Tesla.

James Watt is credited with significantly improving the steam engine in the late 18th century, making it efficient enough to power the Industrial Revolution. While others worked on steam power, Watt's design was the breakthrough.