====Punnett square !!! (Genetics pratice problems)) ====2questions!!?

Question

1.
In goats, a recessive gene causes the goats to faint when they are startled. A farmer breeds 2 goats (that have never fainted) and
their first offspring aints two days after its birth . What must the parent's genotypes have been? show the cross to prove it

2. In guinnea pigs, Short hair is dominant to long hair. ALso in guinnea pigs, black eyes are dominant to red eyes. A male guinnea pig that is heterozygous for both traits is crossed with a female that is long haired and red eyed. WHat are the expected phenotypes of their offspring and in what proportion!?


plz !! answer!!!!!!!!! :(

Answer 1

1. the parents must have both been heterozygous, otherwise there can be no homozygous recessive offspring.

The punnet square has two columns and two rows:

.....F f
F
f

If either parent is homozygous dominant, there can be no ff offspring.

2. Now the male parent can have four possible gametes, while the female is limited to one (she is hom. recessive for both traits). The punnet square has 4 columns and one row:

......SB Sb sB sb
sb

You would expect:
1/4 short hair black eyes
1/4 short hair red eyes
1/4 long hair black eyes
1/4 long hair red eyes

Answer 2

1. Let's call the fainting gene F (dominant not fainting) and f (recessive - fainting). To faint, a goat must have ff, or both recessive genes. If there is one F present, the goat won't faint.

So, the parents must have been Ff. The four possible outcomes of their breeding would be FF, Ff, fF, and ff. Only the kids with ff will faint since all three other possibilities have an F in it.

Answer 3

those are trouble-free, common questions in case you understand the terminology. Do you comprehend that heterozygous signifies that the letters in the genotype do not tournament? (homozygous is tt or TT, heterozygous is Tt) a million. mom and father Tt x tt Gametes T t t t placed those on the Punnett sq. and discover the outcomes. 2. Constricted pods are the recessive type of the trait. If we use uppercase P and lowercase p for this trait, 2 constricted pea vegetation are pp and pp. each and each and every of the offspring are pp because it is the in trouble-free terms type of the gene it is for sale.

Answer 4

We are learning the same thing! I can't post a picture of a punnett square so I can't really help. Don't you have a friend you can call or a parent that can help you?

Answer 5

how are we supposed to show you the answer when you cant post a grid?
and anyway, do your own homework!