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(c) (ii) Write two observations made by Mendel about $\text{F}_1$ progeny.
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(a) In F1 progeny, pea plants have ‘Tt' where ‘T' is dominant over ‘t'
so all the plants of F1 progeny were tall. / Tall height is dominant
trait over short height. (1)
(b) Self-pollination (1)
(c) (i)
Dominant trait
i) Expresses itself over recessive trait.
ii) Expresses in both conditions-TT and Tt. (2)
Recessive trait
i) Unable to express itself in presence of a dominant trait.
ii) Expresses itself only when it is 'tt' or in pure condition. (2)
(any one, any other suitable difference)
OR
(c) (ii) Mendel's observations:
• All plants of F1 progeny were tall.
• No medium/ no short height plants observed in F1 progeny.
• F1 progeny resembled one parent only. (1+1)
(any two observations)
so all the plants of F1 progeny were tall. / Tall height is dominant
trait over short height. (1)
(b) Self-pollination (1)
(c) (i)
Dominant trait
i) Expresses itself over recessive trait.
ii) Expresses in both conditions-TT and Tt. (2)
Recessive trait
i) Unable to express itself in presence of a dominant trait.
ii) Expresses itself only when it is 'tt' or in pure condition. (2)
(any one, any other suitable difference)
OR
(c) (ii) Mendel's observations:
• All plants of F1 progeny were tall.
• No medium/ no short height plants observed in F1 progeny.
• F1 progeny resembled one parent only. (1+1)
(any two observations)