I am somewhat new to this site although I am a member, so I have these questions

Question

I am somewhat new to this site although I am a member, so I have these questions I have answerd most of them my self yet I would like to see if any experts, or people with some knowledge could could go ahead and do them so i can see if I am correct or not. I dont actually expect anybody to be able to make a punnet square, as I myself had to make my punnet squares on paper. But these are the questions below, I will put my answers the ones I have gotten in ( ) but if you are either able to tell me if im correct or if not show me some sort of steps to becoming correct? Thanks Zack Cross.

Solve all of these problems using a Punnett Square. ( I Have done this mostly on paper)

In certain bacteria, an oval shape (A) is dominant over round (a) and thick cell walls (B) are dominant over thin (b). A bacteria heterozygous for both oval shape and a thick cell wall was crossed with a round bacteria with a thin cell wall. Describe the phenotype of the offspring.

(My answer not sure if correct but I got  : Oval Thick wall : Oval Thin wall : Round thick wall: Round thin wall

1:1:1:1)

2. The ability to roll the tongue sideways (A) is dominant over the inability to roll one's tongue (a). In humans, non-attached earlobes (B) are dominant over attached earlobes (b). Two parents with attached earlobes can roll their tongues. They are both heterozygous for the tongue rolling trait.

Any Help would be greatly apretiated I don't understand how the point system works but I did purchase the membership package thing so I do believe I will be able to award someone with these karma points which I purchased.

Explanation / Answer

1.) Your answer is correct...the 4 phenotypes of the offspring are (1) oval shape & thick cell wall, (2) oval shape & thin cell wall, (3) round shape & thick cell wall, (4) round shape & thin cell wall.

2.) 1. The mother's genotype is Aabb because she is heterozygous for the tongue-rolling trait (Aa), but has attached earlobes which is a recessive trait (bb).
2. The father's genotype would be the same as the mother's (Aabb).
3. The possible gametes from the mother are Ab, Ab, ab, and ab.
4. The possible gametes from the father are Ab, Ab, ab, and ab.
5. Offspring (from Punnett square..): 4 (AAbb), 8 (Aabb), 4 (aabb)
6. The phenotypic ratio of these offspring is: (12 tongue-rolling & attached earlobes:4 non-tongue-rolling & attached earlobes) ...which when simplified gives the ratio 3:1.

1.) 1. The genotype of the mother is Aabb.

2. The genotype of the father is AaBb.

3. The possible gametes from the mother are Ab, Ab, ab, and ab.

4. The possible gametes from the father are AB, Ab, aB, and ab.

5. Offspring (from Punnett square..): 2 (AABb), 2 (AAbb), 4 (AaBb), 4 (Aabb), 2 (aaBb), 2 (aabb)

6. The phenotypic ratio of these offspring is: 6 tongue-rolling & attached earlobes:6 tongue-rolling & non-attached earlobes:2 non-tongue-rolling & non-attached earlobes:2 non-tongue-rolling & attached earlobes ...which when simplified gives the ratio 3:3:1:1.

2.) 1. The F1 generation will all have the genotype WwDd and the phenotype of white disk-shaped fruit.

(Cross 2 of the offspring from the F1 generation to produce offspring for the F2 generation..)

2. The F2 generation will have the genotypic ratio of: 1WWDD:2WWDd:1WWdd:2WwDD:4WwDd:2Wwdd:1wwDD:2wwDd:1wwdd (1:2:1:2:4:2:1:2:1) and the phenotypic ratio: 9 white disk-shaped fruit:3 white sphere-shaped fruit:3 yellow disk-shaped fruit:1 yellow sphere-shaped fruit (9:3:3:1).

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