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Question
Gregor Mendel's first law of genetics states "Of a pair of contrasted characters, only one can be represented in a gamete by its internal 'factor' State where these factors are found in gametes.
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Solution
These factors or genes are present on chromosomes in gametes.
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Figures (a) to (d) given below represent the type of ear lobes present in a family consisting of 2 children - Rahul, Nisha and their parents.
|
(a) Rahul's Father |
(b) Rahul |
(c) Rahul's Mother |
(d) Rahul's sister Nisha |
|
(e) |
(f) |
||
| Types of ear lobes | |||
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| Sex | Free | Attached |
| Male | 36 | 14 |
| Female | 31 | 19 |
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(Gene for the Free ear lobe is represented by F and the gene for the attached ear lobe is represented by f for writing the genetic constitution).
OR
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| RRYY | × |
rryy |
| Round, Yellow | Wrinkled, Green |
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