PinkMonkey Online Study Guide-Biology
Reasons for Mendelís success:
i. Mendel concentrated on the
results of one trait at a time.
ii. When the behavior of one trait was established,
only then he considered two
iii. He conducted a large number of crosses (2000-3000)
to eliminate the chance factor
and to obtain a valid and accurate
iv. Most of all, he actually counted the number
of offsprings of each category
and maintained accurate records for each generation
in each experiment.
v. However, luck played a major role in his success
(though Mendel did not know
this fact) in the selection of pea plants
as well as in the selection of those particular seven pairs
of contrasting characters. Because, luckily for Mendel,
in each pair, one form of the character is completely
dominant over the other. Moreover, these seven
characters are present on seven different chromosomes
in the pea plant. However, Mendel was unaware
of this fact.
In nature, there are several instances of incomplete
dominance also. In such cases, the hybrid shows haracter intermediate
between the two parents. For example, in snapdragon, when a parent
plant with red flowers is crossed with another having white flowers, the
F1 hybrids show pink flowers.
Red Flower X
Table of Contents7.0 Introduction
7.1 Gregor Mendel
Mendel's Experiment on Sweet Pea
Law of Dominance
Law of Segregation
Law of Independent Assortment
Test Cross or Back Cross
The Concept of "Factor"