2. Har Gobind Khorana
Har Gobind Khorana (9 January 1922 – 9 November 2011) was an Indian
American biochemist. While on the faculty of the University of Wisconsin–Madison, he
shared the 1968 Nobel Prize for Physiology or Medicine with and Robert W. Holley for
research that showed the order of nucleotides in nucleic acids, which carry the genetic
code of the cell and control the cell's synthesis of proteins. Khorana and Nirenberg were
also awarded the Louisa Gross Horwitz Prize from Columbia University in the same year.
Born in British India, Khorana served on the faculties of three universities in North
America. He became a naturalized citizen of the United States in 1966 and received
the National Medal of Science in 1987.
3. RESEARCH
Ribonucleic acid (RNA) with two repeating units (UCUCUCU → UCU CUC UCU) produced two alternating amino acids. This,
combined with the Nirenberg and Leder experiment, showed that UCU genetically codes for serine and CUC codes
for leucine. RNAs with three repeating units (UACUACUA → UAC UAC UAC, or ACU ACU ACU, or CUA CUA CUA) produced
three different strings of amino acids. RNAs with four repeating units including UAG, UAA, or UGA, produced
only dipeptides and tripeptides thus revealing that UAG, UAA, and UGA are stop codons
Their Nobel lecture was delivered on 12 December 1968. Khorana was the first scientist to chemically
synthesize oligonucleotides This achievement, in the 1970s, was also the world's first synthetic gene; in later years, the
process has become widespread. Subsequent scientists referred to his research while advancing genome editing with the
CRISPR/Cas9 system.
4. Mohinder Singh Randhawa was born on 2 February 1909 into a Randhawa Ja
family at Zira, Ferozepur district, Punjab, India to Sher Singh Randhawa and
Bachint Kaur who came from an affluent family belonging to the village of
Bodlan in Hoshiarpur district. He received his matriculate from Khalsa High
School, Muktsar in 1924 and his F.Sc., BSc (Hons.), and MSc (Hons.) in 1926,
1929 and 1930 respectively from Lahore. In 1955, he was awarded a
Doctorate in Science by the University of the Punjab for his work on algae,
especially on Zygnemataceae.
Mohinder Singh Randhawa
5. Sálim Moizuddin Abdul Ali
Sálim Moizuddin Abdul Ali (12 November 1896 – 20 June 1987)[1] was
an Indian ornithologist and naturalist. Sometimes referred to as the "Birdman of India", Salim Ali
was the first Indian to conduct systematic bird surveys across India and wrote several bird
books that popularized ornithology in India.
6. Gregor Johann Mendel
Gregor Johann Mendel 20 July 1822 – 6 January 1884) was a scientist, Augustinian friar and
abbot of St. Thomas' Abbey in Brno, Margraviate of Moravia
Mendel worked with seven characteristics of pea plants: plant height, pod shape and color, seed
shape and color, and flower position and color. Taking seed color as an example, Mendel showed that
when a true-breeding yellow pea and a true-breeding green pea were cross-bred their offspring
always produced yellow seeds. However, in the next generation, the green peas reappeared at a ratio
of 1 green to 3 yellow. To explain this phenomenon, Mendel coined the terms "recessive" and
"dominant" in reference to certain traits. In the preceding example, the green trait, which seems to
have vanished in the first filial generation, is recessive and the yellow is dominant. He published his
work in 1866, demonstrating the actions of invisible "factors"—now called genes—in predictably
determining the traits of an organism.
7. Experiments on plant hybridization
Gregor Mendel, who is known as the "father of modern genetics", was inspired by both his
professors at the Palacký University, Olomouc (Friedrich Franz and Johann Karl Nestler), and his
colleagues at the monastery (such as Franz Diebl) to study variation in plants. In 1854, Napp
authorized Mendel to carry out a study in the monastery's 2 hectares (4.9 acres) experimental
garden which was originally planted by Napp in 1830 Unlike Nestler, who studied hereditary traits
in sheep, Mendel used the common edible pea and started his experiments in 1856.
After initial experiments with pea plants, Mendel settled on studying seven traits that seemed to
be inherited independently of other traits: seed shape, flower color, seed coat tint, pod shape,
unripe pod color, flower location, and plant height. He first focused on seed shape, which was
either angular or round Between 1856 and 1863 Mendel cultivated and tested some 28,000 plants,
the majority of which were pea plants (Pisum sativum)This study showed that, when true-breeding
different varieties were crossed to each other (e.g., tall plants fertilized by short plants), in the
second generation, one in four pea plants had purebred recessive traits, two out of four
were hybrids, and one out of four were purebred dominant. His experiments led him to make two
generalizations, the Law of Segregation and the Law of Independent Assortment, which later came
to be known as Mendel's Laws of Inheritance
8. Charles Darwin
Charles Robert Darwin 12 February 1809 – 19 April 1882) was an
English naturalist, geologist and biologist, best known for his contributions to the science
of evolution
Darwin published his theory of evolution with compelling evidence in his 1859 book On the Origin of
Species. By the 1870s, the scientific community and a majority of the educated public had
accepted evolution as a fact. However, many favored competing explanations which gave only a minor
role to natural selection, and it was not until the emergence of the modern evolutionary synthesis from
the 1930s to the 1950s that a broad consensus developed in which natural selection was the basic
mechanism of evolution Darwin's scientific discovery is the unifying theory of the life sciences,
explaining the diversity of life
Darwin's early interest in nature led him to neglect his medical education at the University of Edinburgh;
instead, he helped to investigate marine invertebrates. Studies at the University of Cambridge (Christ's
College) encouraged his passion for natural science.[17] His five-year voyage on HMS Beagle established
him as an eminent geologist whose observations and theories supported Charles Lyell's conception of
gradual geological change, and publication of his journal of the voyage made him famous as a popular
author.
9. Lamarckism
Lamarckism, or Lamarckian inheritance, also known as "Neo-Lamarckism", is the notion that an organism can pass on
to its offspring physical characteristics that the parent organism acquired through use or disuse during its lifetime. This
idea is also called the inheritance of acquired characteristics or soft inheritance. It is inaccurately[1][2] named after the
French biologist Jean-Baptiste Lamarck (1744–1829), who incorporated the action of soft inheritance into his
evolutionary theories as a supplement to his concept of orthogenesis, a drive towards complexity. The theory is cited
in textbooks to contrast with Darwinism. This paints a false picture of the history of biology, as Lamarck did not
originate the idea of soft inheritance, which was known from the classical era onwards, and it was not the primary
focus of Lamarck's theory of evolution. Further, in On the Origin of Species (1859), Charles Darwin supported the idea
of "use and disuse inheritance", though rejecting other aspects of Lamarck's theory. Darwin's own concept
of pangenesis implied soft inheritance.
