HELP PLS. In humans, thick eyebrows are dominant to narrow and separated are dominant to joined. Michael has a very thick uniform, and is worried his future children will as well. He is surprised he even has one, since his mother has narrow and separated eyebrows, just like his wife Alexia. Alexia's dad has a unibrow.

Assuming diallelic genes with no interaction between them, 4) There are 25% chances that their children will look like Michael. 5) All phenotypes have the same likelihood of occurrence, 25%.

Available data:

thick eyebrows are dominant to narrow
separated are dominant to joined
Michael has thick and joined eyebrows
Michael's mother has narrow and separated eyebrows
Alexia has narrow and separated eyebrows
Alexia's dad has a unibrow

Let as assume these genes express complete dominance and do not interact.

We will name

T the dominant allele that codes for thick eyebrows

t to the recessive allele that codes for narrow eyebrows

S the dominant allele that codes for separated eyebrows

s the recessive allele that codes for joined eyebrows.

Let us see the genotypes of alexia and michael.

Michael genotype

He is unibrow so his genotype for this trait is ss, h0m0zyg0us recessive.

He has a thick eyebrow so he can be either TT or Tt. Since his mother has narrow eyebrow, she is h0m0zyg0us recessive for this trait. Then Michael must have inherited the recessive allele from her, which means that Michael is heter0zyg0us for the trait, Tt.

Michael's genotype is Tt ss

Alexias genotype

She has narrow eyebrows, so her genotype for this traits is h0m0zyg0us recessive, tt.

She has separated eyebrows, which means she can be either SS or Ss. Since her father has unibrow (ss) she must have inherited the recessive allele from him. Then Alexia is heter0zyg0us for the trait.

Alexia's genotype is tt Ss

Now let us perform the cross.

Parentals) Tt ss x tt Ss

Gametes) Ts, Ts, ts, ts tS, ts, tS, ts

Punnett square) Ts Ts ts ts

tS TtSs TtSs ttSs ttSs

ts Ttss Ttss ttss ttss

F1)

4/16 = 1/4 = 25% of the progeny is expected to be heter0zyg0us for both traits, expressing thick and separated eyebrows.

4/16 = 1/4 = 25% of the progeny is expected to be ttSs, expressing narrow and separated eyebrows.

4/16 = 1/4 = 25% of the progeny is expected to be Ttss, expressing thick and joined eyebrows.

4/16 = 1/4 = 25% of the progeny is expected to be ttss, expressing narrow and joined eyebrows.

4) There are 25% chances that their children will look like Michael, expressing thick and joined eyebrows, Ttss.

5) All phenotypes have the same likelihood of occurrence, 25%.

25% TtSs thick and separated eyebrows.

25% ttSs narrow and separated eyebrows.

25% Ttss thick and joined eyebrows.

25% ttss narrow and joined eyebrows.

You can learn more about two genes crosses at

https://brainly.com/question/11105396