Use the forked-line method to solve this problem (SHOW YOUR WORK): In cucumbers, there are 3 genetic traits, as follows: dull fruit is dominant to glossy fruit orange fruit color is dominant to cream fruit color bitter cotyledons are dominant to nonbitter cotyledons You cross a plant that is heterozygous for all 3 genes to another plant that is heterozygous for dull fruit but has cream fruit color and nonbitter cotyledons. Among the next generation, what proportion of the offspring will be a) dull, orange, bitter b) glossy, cream, nonbitter c) heterozygous for all 3 genes (HINT: it's not the same answer as a) above

a) dull, orange, bitter >  3/16 D- Oo Bb

b) glossy, cream, nonbitter ---> 1/16 dd oo bb

c) heterozygous for all 3 genes ---> 2/16 Dd Oo Bb

Explanation:

Available data:

Parentals) Dd Oo Bb     x    Dd oo bb

To get the proportions of the offspring using the forked-line method, we must analyze each gene separately.

D gene:

Parentals) Dd    x    Dd

Gametes ) D   d    D    d

Punnett square)      D      d

                        D   DD    Dd

                        d    dD     dd

F1) 1/4 DD

     2/4 Dd

     1/4 dd

O gene:

Parentals) Oo    x    oo

Gametes) O    o     o     o

Punnett square)     O      o

                        o    Oo     oo

                         o    Oo    oo

F1) 1/2 Oo

     1/2 oo

B gene:

Parentals) Bb    x    bb

Gametes) B   b      b    b

Punnett square)   B        b

                  b         Bb      bb

                  b         Bb      bb

F1) 1/2 Bb

     1/2 bb

What proportion of the offspring will be

a) dull, orange, bitter

   (1/4 DD + 2/4 Dd) x 1/2 Oo x 1/2 Bb = 3/4 D- x 1/2 Oo x 1/2 Bb

   3/16 D- Oo Bb

b) glossy, cream, nonbitter

   1/4 dd x 1/2 oo x 1/2 bb

   1/16 dd oo bb

c) heterozygous for all 3 genes

    2/4 Dd x 1/2 Oo x 1/2 Bb

    2/16 Dd Oo Bb

tsd is temerature dependent sex determination.

tsd: it is a type of environmental sex determination in which the temperature experienced during embryonic/ larval development (ambient temperature for development) determine the sex of the offspring.

crocodile displays the tsd where the ambient temperature of the developing egg determines the individual's sex. for example in the american alligator's eggs, incubation at 33 ºc produces mostly males, while incubation at 30 ºc produces mostly females. so if the american alligator's egg will get the ambient temperature (33 degree celcius)during embryonic development from egg, the offspring will be male and same for the female sex determination.