Question

What are the parents blood genotypes? Which child was adopted? Expain.... Question: Mary has type A blood and her husband has type B. Her husbands parents both have type AB. They have three children. One has type A, one type B and one type AB.

Answer 1

We can keep talking about this here.

Answer 2

Again, in blood type, there are three different alleles.

( A ), ( B ), and ( i ).

( A ) and ( B ) are Dominant alleles.
( i ) is a recessive allele.

Answer 3

So the mom is just IAIA, not Iai

Answer 4

I mean IAi for mom

Answer 5

The mom is (A i)

Answer 6

Now, take a look at the husband.

His parents are both (A B).

And the husband has Type B blood.

Do you know the two genotypes that would make someone Type B?

Answer 7

(Bi and BI)

Answer 8

(B i) and (B B).

Answer 9

So the dad is Bi? little confused

Answer 10

Ah crap actually BB cause his parents gave him each a B

Answer 11

RIght.

Answer 12

Ok so how do I figure out which one or if there really is an adopted kid.

Answer 13

In your book, (B B) actually looks like this....\[i^{B}i^{B}\]

But we're just gonna say (B B).

Answer 14

Okay so you know the genotypes of mom and dad, right?

Mom is (A i)
and dad is (B B).

Answer 15

right

Answer 16

We also know the blood types of the children.

Type A
Type AB
Type B

Answer 17

Let's start with Type AB.

Could these two parents have a child with type AB blood?

Answer 18

sure

Answer 19

Right.

This child got an (A) from mom
and a (B) from dad.

Answer 20

That makes AB.

Answer 21

Let's look at the Type B child now.

Could these two parents have a Type B child?

Answer 22

Remember....

Mom is (A i)
Dad is (B B)

Answer 23

little i is recessive right

Answer 24

Yes.

Answer 25

Ok so I'm going to say yes but man I'm not sure

Answer 26

It is yes.

If the child got a (B) from dad,
and an ( i ) from mom...

then the child's genotype would be (B i)

That's a Type B blood.

Answer 27

Ok got it. then child A must of been adopted. because dad is BB

Answer 28

Right.

There's no way these two parents could have a Type A child.

That means that the mom cheated on her husband, and had that Type A child with someone else.

Answer 29

because type A genotypes are Ai or AA

Answer 30

Exactly.

Answer 31

got it. your awesome and my teacher sucks

Answer 32

I'm glad you were able to understand.

Answer 33

Ok I got one more I think I did it right but I'd like you to take a look. ok

Answer 34

Sure.

Answer 35

A recesssive mutant allele, black. causes a very dark body in Drosophila when homozygous. The normal wild type color is gray. Questions: A black female is crossed to a heterozygous gray male. What are the parental genotypes? What F1 phenotypic and genotypic ratios are produced from this cross? Need punnett square

Answer 36

So we need to make up some alleles.

Let's pretend ( B ) is Normal,
and ( b ) is black.

Answer 37

ok

Answer 38

It says that black is recessive.
That's why we used a lowercase ( b ).

Answer 39

It also says that black only happens when the genotype is homozygous.

Do you remember what that means?

Answer 40

the same

Answer 41

Right.

If my genotype is (b b),
then I am black.

That is the ONLY genotype that will cause a black phenotype.

Answer 42

So if the alleles are (B) and (b)....then what would the heterozygous genotype be?

Answer 43

Bibi.. crap I dont know.. This stuff kicks my butt

Answer 44

lol We aren't talking about blood anymore.

Answer 45

This is just like what we did yesterday.

Answer 46

The alleles are (B) and (b).
Those are the letters that we can use.

Homozygous means "same," like you said.
Heterozygous means "different."

The genotype (b b) causes the flies (insects) to turn black.

Answer 47

You follow so far?

Answer 48

ok

Answer 49

So...the paragraph tells us that a Homozygous Recessive genotype causes the flies to turn black.

That would be (b b).
Homozygous, AND recessive.

Answer 50

Earlier, I asked what the Heterozygous genotype would be.

That would be (B b).

You see?
Both different letters.

Answer 51

ok I'm following

Answer 52

Alright.
So let's read the paragraph again.

"A black female is crossed to a heterozygous gray male."

Answer 53

Those are the parents.

Answer 54

We need to know their genotypes.

Answer 55

The female is black.

So what is the only genotype that she could have?

Answer 56

bb

Answer 57

Yes.

Now, I gotta tell you,
"Wild type" is just another way of saying "normal."

The male is heterozygous.
He's gray, which is Normal.

What's his genotype?

Answer 58

Bb

Answer 59

Right.

So now we know the answer to the first question.

The parental genotypes are (b b) and (B b).

Answer 60

Now,
we need to make a Punnett Square,
and figure out all the possible genotypes for their children.

Answer 61

I don't understand F1 phenotypic and how to do genotypic ratios

Answer 62

That's the F1 generation. Their children.

Answer 63

The parents are...well...the parents.

The F1 generation is their children.

Answer 64

ok so when I see P1 thats the parents

Answer 65

Yeah.

Answer 66

I wish my jack retriceteacher would tell us that

Answer 67

Jack retricelol

Answer 68

lol

So do you know how to make Punnett Squares?

Answer 69

Not using my computer which stinks cuz I need too.