All categories

3 years ago

What is the probability that the first offspring from the cross listed below will be heterozygous for all loci?

Biology

1 answer:

Tanya [424]3 years ago

6 0

Answer and Explanation:

Cross: aa Bb dd Ee x AA bb Dd Ee

We can calculate the probability of getting heterozygous individuals in the progeny by using the product rule. Assuming that these four genes assort independently (events that occur independently from each other), we can infer that the F1 will have the next genotypic proportions for each gene:

1) aa x AA

F1) 4/4=1 Aa

2) Bb x bb

F1) ½ bb

½ Bb

3) dd x Dd

F1) ½ dd

½ Dd

4) Ee x Ee

F1) ¼ EE

2/4 = ½ Ee

¼ ee

So, to know what the probability is that the F1 of being heterozygous for all loci, we must multiply the respective individual probabilities of getting a heterozygous genotype, like this:

1 Aa x ½ Bb x ½ Dd x ½ Ee = 1/8 AaBbDdEe

You might be interested in

If you ate more food from secondary consumers, how would this change the percentage of the biomass pyramid necessary to support

Anna007 [38]

Answer:

would increase

Explanation:

The pyramid of biomass is a diagram that exhibits the total biomass of the organisms at different trophic levels, which are required to support life in a given ecosystem. This pyramid usually starts with producers situated on the bottom (e.g., plants), then continues with the organisms that eat these primary consumers (herbivores), after with secondary consumers (carnivores), and so successively. The pyramid of biomass indicates the amount of mass of 1-primary producers required to support the life of the primary consumers, 2- primary consumers needed to support the life of the secondary consumers, 3-secondary consumers needed to support the life of the tertiary consumers, and so successively for each trophic level. In this diagram, the trophic level with a higher amount of biomass (and energy) is usually represented by the producers (i.e., by organisms on the bottom), and this amount of biomass decreases as long as more levels are considered. In consequence, if more food from secondary consumers is consumed, it will produce an increase in the percentage of biomass that is needed to support life.

5 0

3 years ago

the couple is also concerned about their child inheriting hemophilia, another rare disease, which is x-linked. natalie’s brother

IgorC [24]

Hemophilia is a recessive X-linked condition and is inherited from parents. . The probability that Natalie and Daniel’s first child has hemophilia is 1/4, not 1/8. The statement is false.

<h3>What is an X-linked gene?</h3>

When talking about sex-linked genes, we refer to all those genes located in one of the sex-chromosomes and not in the somatic ones.

X-linked genes are the genes located specifically in the X sex chromosome.

Traits coded by these genes are inherited. This is, X-linked genes are transmitted from parents to children through generations.

According to this, X-linked genetic disorders will be inherited as well.

Men have a high probability of being affected since they only have one copy of the X chromosome.

In women, the effect of the mutation might be musk in heterozygous state if the mutation is recessive.

Hemophilia is a recessive X-linked disorder, which means it is coded by the recessive allele.

X+ ⇒ X chrosomosome with Dominant allele

X- ⇒ X chrosomosome with Recessive allele

Genotype Phenotype

X+X+ Healthy woman

X+X- Healthy carrier woman

X-X- Hemophilic woman

X+Y Healthy man

X-Y Hemophilic man

Let us make a pedigree of these families,

Natalie's family:

Mother healthy carrier X+X-

Father healthy X+Y

Brother hemophilic X-Y

Natalie Healthy X+X- or X+X+

Natalie has 1/2 chances of being carrier X+X- and 1/2 of being X+X+.

Daniel's family:

Mother healthy carrier X+X-

Father hemophilic X-Y

Sister hemophilic X-X-

Daniel Healthy X+Y

He has 1/2 chances of being healthy X+Y and 1/2 of being affected X-Y.

According to the product probability rule, if events A and B are independent from each other, the probability of occurrence of both events together is

P(A∩B) = P(A) x P(B)

In this case,