Smooth edged leaves (S) dominant over rough edged leaves (s). Two plants heterozygous for smooth edged leaves are crossed. What proportion of the offspring are expected to be smooth edged leaves?

a. 1/4 b. 1/2 c. 3/4 d. 1

3/4

i'd say 3/4, but not for sure

Well, when it comes to plants, sometimes genetics can get a little bit leafy. In this case, we have smooth edged leaves (S) being dominant over rough edged leaves (s). So, if we cross two plants that are heterozygous for smooth edged leaves, where they each carry one copy of the smooth allele and one copy of the rough allele, what proportion of the offspring are expected to be smooth?

Let's break it down. When the two plants are crossed, we can use a Punnett square to see all the possible combinations of alleles in their offspring.

S s
------------------------
S | SS | Ss |
------------------------
s | Ss | ss |
------------------------

So, as you can see, there are two genotypes that lead to smooth leaves: SS and Ss. That means, out of the four possible combinations, three of them have at least one S allele.

Therefore, the proportion of the offspring expected to have smooth edged leaves is 3/4, or option (c). And hey, with that kind of smoothness in their leaves, those plants are going to be the envy of the botanical world.

To determine the proportion of offspring expected to have smooth edged leaves, we need to use the principles of Mendelian genetics. In this case, smooth edged leaves (S) are dominant over rough edged leaves (s).

Since both parent plants are heterozygous for smooth edged leaves (Ss), the possible combinations of alleles they can pass on to their offspring are: SS, Ss, Ss, and ss.

Now, we can create a Punnett square to determine the possible genotypes of the offspring:

| S | s |
_______|_________|_________|
S | SS | Ss |
_______|_________|_________|
s | Ss | ss |
_______|_________|_________|

From the Punnett square, we can see that there are 3 possible genotypes for the offspring: SS, Ss, and ss.

The genotypes SS and Ss both correspond to smooth edged leaves (S), while the genotype ss corresponds to rough edged leaves (s).

Since the proportion of offspring with smooth edged leaves is equal to the proportion of genotypes SS and Ss, we can conclude that the expected proportion of offspring with smooth edged leaves is 3/4, which corresponds to option c.

How would you determine is wrinkled leaves or smooth leaves is the dominant factor in a true breeding plant

Blah**** Find the answer out yourself.... do the wrok