an angiosperm plant having red coloured flowers when crossed with the other having the same colour produced 40 progenies out of which 30 plants were red coloured flowers 10 plants were with white coloured flowers .Find out
A} what is the possible genotype of parent plants?
B} which trait is dominant and ressesive?
C} what is their cross called as and what is it phenotypic ratio?
Answers
Both the parent plants are heterozygous with a dominant allele for the red color. The dominant allele is the one for the red colored flowers( can be represented by R) and the recessive one is of the white colored flowers (can be represented by a small w).
That is: Rw
Attached is the punnet square for the genetic cross.
B) The dominant trait and the recessive trait:
The Red colored trait is dominant and the white colored trait is recessive, the reason why the Red is expressed in the parents and not the white.
C) Name of the cross and the phenotypic ratio:
As you can see from the punnet square attached, the results of the cross are:
RR, RR, Rr and rr
Every offspring with a R will have the color red and without R will be white. Hence the probability is that 75% will be red in color while 25% white in color. Meaning for every 4 offspring 3 offspring 3 will likely be red and 1 white.
This gives a ratio of :
75:25 = 3:1
The name of the cross is:
This is a monohybrid cross. It is monohybrid because it involves one gene locus, locus for color.
Answer:
A) Possible genotype for parent plants:
Both the parent plants are heterozygous with a dominant allele for the red color. The dominant allele is the one for the red colored flowers( can be represented by R) and the recessive one is of the white colored flowers (can be represented by a small w).
That is: Rw
Attached is the punnet square for the genetic cross.
B) The dominant trait and the recessive trait:
The Red colored trait is dominant and the white colored trait is recessive, the reason why the Red is expressed in the parents and not the white.
C) Name of the cross and the phenotypic ratio:
As you can see from the punnet square attached, the results of the cross are:
RR, RR, Rr and rr
Every offspring with a R will have the color red and without R will be white. Hence the probability is that 75% will be red in color while 25% white in color. Meaning for every 4 offspring 3 offspring 3 will likely be red and 1 white.
This gives a ratio of :
75:25 = 3:1
The name of the cross is:
This is a monohybrid cross. It is monohybrid because it involves one gene locus, locus for color
Explanation
: