You find a plant in a field that produces red flowers but...

You find a plant in a field that produces red flowers (but have no idea what strains were crossed to produce it). You take the flower back to your lab and cross it with a plant of the same species that you know is true breeding for white flowers. Half of the offspring have red flowers, and half have white flowers. What was the genotype of the plant you found in the field? Assume that flower color is controlled by Mendelian inheritance (complete dominance). Select one: a. homozygous dominant b. homozygous recessive c. it cannot be determined from the information provided d. heterozygous

Transcript

0:00 Hello students.

00:01 In this question, they have given that there's a species of roses wherein the red flower, red flower color color will dominate the white flower color.

00:10 So there's a scientist who will self -fertilize a red flower plant.

00:16 And he doesn't know the genotype of these two.

00:18 He just knows that the phenotype is red.

00:20 So in this case, slightly to analyze this situation, we can say that it has one dominant trait, correct? as a result of which we are observing that there's a red color phenotype.

00:35 And one more thing he's observing is that 26 of them were red flowered and 11 of them were white flowered.

00:42 If you observe this, this is somewhat in the ratio of 3 to 1, right? if you see 26 by 11 if you do, it's almost equivalent to 3 to 1.

00:53 Correct? so we can say that this is a monohybrid cross that we.

00:58 Will see, right? since there is white that is being observed in this case, we can obviously say that the genotype of the original parent, right? the genotype of the parent, we can say that it is nothing but rr and rr, right? so, here you're observing that the rr will give you red, right? and this rr will give you the heterozygous red.

01:32 Same with this case, that is heterozygous red, and you are getting one white.

01:37 So these three together are 26 flowers and this together is 11 flowers, right? so that way we can say that this is the parent, correct? coming to the next part...

Question

Please give Ace some feedback