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if both parents are heterozygous for a trait,the probability that an offspring will be recessive...

if both parents are heterozygous for a trait,the probability that an offspring will be recessive for that trait is?

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Answer
1/4

A genotype such as either BB or bb the alleles are identical. An individual with this type of genotype is called homozygous. For a genotype such as Bb the alleles are different from one another. An individual with this type of pairing is called heterozygous.

Parents and Offspring
Two parents each have a pair of alleles. Each parent contributes one of these alleles. This is how how the offspring obtains its pair of alleles. By knowing the genotypes of the parents, we can predict the probability what the offspring's genotype and phenotype will be. Essentially the key observation is that each of a parent's alleles has the probability of 50% of being passed down to an offspring.

Let's go back to the eye color example. If a mother and father are both brown eyed with heterozygous genotype Bb, then they each have probability of 50% of passing on the dominant allele B and a probability of 50% of passing on the recessive allele b. The following are the possible scenarios, each with probability of 0.5 x 0.5 = 0.25:

Father contributes B and mother contributes B. The offspring has genotype BB and phenotype of brown eyes.
Father contributes B and mother contributes b. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes B. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes b. The offspring has genotype bb and phenotype of blue eyes
isaaq

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Answers (5)

Gaby
4 months ago
A genotype such as either BB or bb the
alleles are identical. An individual with this
type of genotype is called homozygous. For
a genotype such as Bb the alleles are
different from one another. An individual
with this type of pairing is called
heterozygous.
Parents and Offspring
Two parents each have a pair of alleles.
Each parent contributes one of these alleles.
This is how how the offspring obtains its
pair of alleles. By knowing the genotypes of
the parents, we can predict the probability
what the offspring's genotype and
phenotype will be. Essentially the key
observation is that each of a parent's alleles
has the probability of 50% of being passed
down to an offspring.
Let's go back to the eye color example. If a
mother and father are both brown eyed
with heterozygous genotype Bb, then they
each have probability of 50% of passing on
the dominant allele B and a probability of
50% of passing on the recessive allele b.
The following are the possible scenarios,
each with probability of 0.5 x 0.5 = 0.25:
Father contributes B and mother
contributes B. The offspring has genotype
BB and phenotype of brown eyes.
Father contributes B and mother
contributes b. The offspring has genotype
Bb and phenotype of brown eyes.
Father contributes b and mother
contributes B. The offspring has genotype
Bb and phenotype of brown eyes.
Father contributes b and mother
contributes b. The offspring has genotype
bb and phenotype of blue eyes
Maranatha
4 months ago
The answer is 1/4'


If you do your cross matching, you'll find out that only 1 out of 4 off them will have 'tt'

Where

'T' is dominant for the trait
't' is reccessive
'TT' is homozygous dominant, 'Tt' is heterozygous.


After cross matching , the results will be in this order.


TT, Tt, Tt, tt.




Thus only one recessive 'tt'
1/4
Kingsley
4 months ago
If a genotype such as either BB or bb the alleles are identical. An individual with this type of genotype is called homozygous. For a genotype such as Bb the alleles are different from one another. An individual with this type of pairing is called heterozygous.

Parents and Offspring
Two parents each have a pair of alleles. Each parent contributes one of these alleles. This is how how the offspring obtains its pair of alleles. By knowing the genotypes of the parents, we can predict the probability what the offspring's genotype and phenotype will be. Essentially the key observation is that each of a parent's alleles has the probability of 50% of being passed down to an offspring.

Let's go back to the eye color example. If a mother and father are both brown eyed with heterozygous genotype Bb, then they each have probability of 50% of passing on the dominant allele B and a probability of 50% of passing on the recessive allele b. The following are the possible scenarios, each with probability of 0.5 x 0.5 = 0.25:

Father contributes B and mother contributes B. The offspring has genotype BB and phenotype of brown eyes.
Father contributes B and mother contributes b. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes B. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes b. The offspring has genotype bb and phenotype of blue eyes
delibee
4 months ago
A genotype such as either BB or bb the
alleles are identical. An individual with this
type of genotype is called homozygous. For
a genotype such as Bb the alleles are
different from one another. An individual
with this type of pairing is called
heterozygous.
Parents and Offspring
Two parents each have a pair of alleles.
Each parent contributes one of these alleles.
This is how how the offspring obtains its
pair of alleles. By knowing the genotypes of
the parents, we can predict the probability
what the offspring's genotype and
phenotype will be. Essentially the key
observation is that each of a parent's alleles
has the probability of 50% of being passed
down to an offspring.
Let's go back to the eye color example. If a
mother and father are both brown eyed
with heterozygous genotype Bb, then they
each have probability of 50% of passing on
the dominant allele B and a probability of
50% of passing on the recessive allele b.
The following are the possible scenarios,
each with probability of 0.5 x 0.5 = 0.25:
Father contributes B and mother
contributes B. The offspring has genotype
BB and phenotype of brown eyes.
Father contributes B and mother
contributes b. The offspring has genotype
Bb and phenotype of brown eyes.
Father contributes b and mother
contributes B. The offspring has genotype
Bb and phenotype of brown eyes.
Father contributes b and mother
contributes b. The offspring has genotype
bb and phenotype of blue eyes
isaaq
4 months ago
Answer
1/4

A genotype such as either BB or bb the alleles are identical. An individual with this type of genotype is called homozygous. For a genotype such as Bb the alleles are different from one another. An individual with this type of pairing is called heterozygous.

Parents and Offspring
Two parents each have a pair of alleles. Each parent contributes one of these alleles. This is how how the offspring obtains its pair of alleles. By knowing the genotypes of the parents, we can predict the probability what the offspring's genotype and phenotype will be. Essentially the key observation is that each of a parent's alleles has the probability of 50% of being passed down to an offspring.

Let's go back to the eye color example. If a mother and father are both brown eyed with heterozygous genotype Bb, then they each have probability of 50% of passing on the dominant allele B and a probability of 50% of passing on the recessive allele b. The following are the possible scenarios, each with probability of 0.5 x 0.5 = 0.25:

Father contributes B and mother contributes B. The offspring has genotype BB and phenotype of brown eyes.
Father contributes B and mother contributes b. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes B. The offspring has genotype Bb and phenotype of brown eyes.
Father contributes b and mother contributes b. The offspring has genotype bb and phenotype of blue eyes
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