BIOLOGY
575
CHAPTER 2
Fundamentals of Genetics
(5]
Give the phenotype and genotype of the F, generation.
Which type of pollination has occurred to produce F, generation?
Write the phenotypic ratio of the F, generation.
Write the possible combinations of the gametes that can be obtained if two F
hybrid plants are crossed.
(iv) State Mendel's law of “Segregation of Gametes'.
What is the scientific name of the plant which Mendel used for his experiments
(ili
on inheritance ?
2017
Zb) A pea plant which is homozygous for Green pods which are inflated (GGII) is crossed
with a homozygous plant for yellow pods which are constricted Iggii).
Answer the following questions :
Answers
Explanation:
Mendel’s experiments
Gregor Mendel was born in the district of Moravia, then part of the Austro-Hungarian Empire. At the end of high school, he entered the Augustinian monastery of St. Thomas in the city of Brünn, now Brno of the Czech Republic. His monastery was dedicated to teaching science and to scientific research, so Mendel was sent to a university in Vienna to obtain his teaching credentials. However, he failed his examinations and returned to the monastery at Brünn. There he embarked on the research program of plant hybridization that was posthumously to earn him the title of founder of the science of genetics.
Mendel’s studies constitute an outstanding example of good scientific technique. He chose research material well suited to the study of the problem at hand, designed his experiments carefully, collected large amounts of data, and used mathematical analysis to show that the results were consistent with his explanatory hypothesis. The predictions of the hypothesis were then tested in a new round of experimentation.
Mendel studied the garden pea (Pisum sativum) for two main reasons. First, peas were available from seed merchants in a wide array of distinct shapes and colors that could be easily identified and analyzed. Second, peas can either self (self-pollinate) or be cross-pollinated. The peas self because the male parts (anthers) and female parts (ovaries) of the flower—which produce the pollen containing the sperm and the ovules containing eggs, respectively—are enclosed by two petals fused to form a compartment called a keel .The gardener or experimenter can cross (cross-pollinate) any two pea plants at will. The anthers from one plant are removed before they have opened to shed their pollen, an operation called emasculation that is done to prevent selfing. Pollen from the other plant is then transferred to the receptive stigma with a paintbrush or on anthers themselves . Thus, the experimenter can choose to self or to cross the pea plants.