Question 1

A cross of two Kerry horses always produces Kerry offspring.A cross of a Kerry with a Dexter produces 1/2 Kerry and 1/2 Dexter offspring.Crosses of two Dexters produce two Dexters for every Kerry.This pattern of inheritance,in which the F2 generation deviates from the expected ratios,suggests a _______ homozygous recessive trait.

Accepted Answer

The answer of A cross of two Kerry horses always...

Question 2

In a certain breed of chicken,two genes control color.A dominant allele (I)inhibits the expression of any color gene (C).The recessive allele (c)results in albinism when homozygous (cc).The F2 phenotypic ratios of a cross between a colored chicken (ii CC)with a white chicken (II cc)would be ____white,_____ colored.

Accepted Answer

The answer of In a certain breed of chicken,two genes...

Question 3

In sweet peas,dominant alleles C and P are necessary for colored flowers.In the absence of either (__ pp or cc __)or both (cc pp),the flowers are white.A cross between a plant with colored flowers and a plant with white flowers that produced 38 plants with colored flowers and 42 plants with white flowers could be written as _______.

Accepted Answer

The answer of In sweet peas,dominant alleles C and P...

Question 4

There are three alleles controlling the ABO blood types.IA and IB are codominant genes so that the combination IAIB produces the AB blood type.The third allele,i,is recessive to the other two alleles.Which of the following combinations of parents (with blood types on the left)and child (with blood type listed on the right)is NOT possible?

Accepted Answer

A parent with type A only has IAIA or IAi alleles, and a parent with type AB has IAIB alleles. Therefore, it is impossible for their child to have type O, which requires ii alleles. A cross between A and AB (IAi x IAIB) can only produce A, B, or AB blood types.

Question 5

In tomatoes,red (R)is dominant to yellow (r),tall (D)is dominant to dwarf (d),and smooth (H)is dominant to hairy (h).How many possible different phenotypes are there in relationship to these three characteristics?

Accepted Answer

Each characteristic has two possible phenotypes (dominant and recessive), so with three characteristics, the number of possible phenotypes is 2^3 = 8.

Question 6

In poultry,the genes for rose comb (R)and pea comb (P)produce walnut whenever they occur together (R__ P__); single-combed individuals have the homozygous condition for both genes (rr pp).Give the phenotypic results of a cross of Rr Pp x rr Pp

Accepted Answer

The Punnett square for the cross is:

| R | r |
---|---|---|
P |RP | rP |
p |Rp | rp |

From this square, we can see that:

- 3/8 of the offspring will have walnut comb (RP or Rp)
- 3/8 of the offspring will have pea comb (rP or rp)
- 1/8 of the offspring will have rose comb (rP)
- 1/8 of the offspring will have single comb (rp)

Question 7

In a certain breed of chicken,an incompletely dominant gene controls color.The homozygous black (BB),when crossed with the homozygous splashed-white (bb),produces an intermediate gray color pattern referred to as blue.A second gene controls the shape of the comb.The dominant allele (R)produces rose,whereas the recessive allele (r)produces single.A cross between a true-breeding black with a single comb and a true-breeding splashed-white with a rose comb will produce a total of _______ different phenotypes in the F2 generation.

Accepted Answer

The answer of In a certain breed of chicken,an incompletely...

Question 8

True-breeding yellow guinea pigs crossed with true-breeding white ones produce only cream-colored offspring.This pattern indicates incomplete dominance.Rough hair is found to be dominant to smooth hair.Select the F1 genotypic and phenotypic ratios of a cross between a smooth,white guinea pig with a homozygous,rough,yellow guinea pig from the following choices.

Accepted Answer

The answer of True-breeding yellow guinea pigs crossed with true-breeding...

Question 9

White fruit color in summer squash is influenced by a dominant allele W,whereas colored fruit must be ww.In the presence of ww,a dominant gene G results in yellow fruit,and homozygous gg results in green fruit.The F2 phenotypic ratios resulting from a cross of a true-breeding plant with white fruit (genotype WW GG)with a plant with green fruit will result in which phenotypic ratios?

Accepted Answer

The true-breeding plant with white fruit (WW GG) can only produce gametes with W and G alleles. The plant with green fruit must be homozygous for the recessive w allele (ww gg) and can only produce gametes with w and g alleles. 
Therefore, the F1 offspring will all be heterozygous (Ww Gg) for both traits and will have white fruit. 
When these F1 offspring are crossed, the expected phenotypic ratio in the F2 generation is 9:3:3:1 for white-yellow-green. 
However, we have to remember that the green fruit trait is recessive and only appears when an individual is homozygous for the gg genotype. 
Therefore, out of the 16 total possible offspring, there will only be 1 that is green (gg ww), while the remaining 15 offspring will have at least one dominant allele and have white or yellow fruit. 
The most likely outcome is 12/16 white, 3/16 yellow, and 1/16 green.

Question 10

In the late 1920s,a mutation occurred in many silver fox farms around the world.The fox farms that sold expensive furs were proud of the quality of their furs,and each advertised that it had the best,purest breed of all the fox farms.The new mutations produced a "platinum" coat pattern that was commercially desirable,so the farms crossed them to get more.The results of their breeding experiments were as follows: (1)silver ´ silver >>> all silver offspring; (2)silver ´ platinum >>> equal numbers of silver and platinum; (3)platinum ´ platinum >>> two platinum for each silver offspring.Which of the following inheritance patterns explain the breeding results?

Accepted Answer

The breeding results suggest that the platinum trait is recessive and that homozygosity for the platinum allele may cause lethal effects, as indicated by the unexpected ratio in the platinum x platinum cross.

Question 11

In the garden pea,Mendel found that tall ( D )plants,green pods ( G ),and inflated pods ( C )were dominant to dwarf (d )plants,yellow pods ( g ),and constricted pods ( c ). Determine the chances of producing the offspring D__ G__ cc from a cross of D d  G g C c  x  D d  G g  C c.

Accepted Answer

To find the probability of producing offspring with the genotype D__ G__ cc from the cross Dd Gg Cc x Dd Gg Cc, we need to consider each trait separately and then multiply the probabilities.1. For the D trait (tallness), the offspring must be D_ (either DD or Dd). The probability of getting a D allele from one parent is 3/4 (either DD, Dd, or dD, but not dd). Since the trait is considered from both parents independently, the probability remains 3/4.2. For the G trait (green pods), the probability is the same as for the D trait, 3/4, because the genetic situation is identical.3. For the C trait (inflated vs. constricted pods), we want cc, which means getting a c from both parents. The probability of getting a c from one parent is 1/2 (either Cc or cC, but not CC or cc for a single allele). So, the probability of getting cc from both parents is 1/2 * 1/2 = 1/4.Multiplying these probabilities together gives us the overall probability: 3/4 (for D) * 3/4 (for G) * 1/4 (for cc) = 9/64.

Question 12

Congenital deafness in humans is due to the homozygous condition of either of the recessive alleles d or e,or both.Both dominant D and E are necessary for normal hearing.Gene D/d affects the middle ear,while gene E/e affects the inner ear.It does not matter how good the normal inner ear (as indicated by E__)is; if there is something wrong in the middle ear,the individual is unable to hear.The same applies for the other gene.What is the phenotypic result of the cross Dd EE x Dd EE?

Accepted Answer

Given that both dominant alleles D and E are necessary for normal hearing, and each parent is heterozygous for D (Dd) but homozygous dominant for E (EE), the offspring will inherit the E allele from both parents, ensuring normal inner ear function. However, the Dd x Dd cross for the middle ear gene follows a Mendelian inheritance pattern, resulting in a 3:1 ratio of normal hearing (DD or Dd) to deaf (dd). Therefore, 3/4 of the offspring will have normal hearing, and 1/4 will be deaf due to the homozygous recessive condition (dd) affecting the middle ear.

Question 13

In radishes,two incompletely dominant genes control color and shape.Red (R)is dominant over white (r),and heterozygotes are purple.Long (L)is dominant over round (l),and heterozygotes are oval.If a true-breeding long,red radish is crossed with a purple oval radish,give the F1 phenotypes and their percentages.

Accepted Answer

The true-breeding long, red radish must have the genotype RRLl (since it is crossed with a purple, oval radish which is heterozygous for both traits, indicating the true-breeding radish must contribute the recessive l allele for shape). The purple, oval radish has the genotype RrLl. The F1 generation will show a 1:1:1:1 phenotypic ratio due to the independent assortment and incomplete dominance of both traits, resulting in 25% long red, 25% long purple, 25% oval red, and 25% oval purple.

Question 14

Heritable units of information about traits are called __________.

Accepted Answer

The answer of Heritable units of information about traits are...

Question 15

If you were following the inheritance patterns of two different sets of multiple alleles located on different chromosomes,with locus 1 having five possible alleles and locus 2 having six alleles,there would be a total of _____ different possible gametes produced.

Accepted Answer

The answer of If you were following the inheritance patterns...

Question 16

In sweet peas,dominant alleles C and P are necessary for colored flowers.In the absence of either (__ pp or cc __)or both (cc pp),the flowers are white.What the phenotypic ratios be for the cross of Cc pp x cc Pp?

Accepted Answer

The answer of In sweet peas,dominant alleles C and P...

Question 17

Different molecular forms of the same gene are __________.

Accepted Answer

The answer of Different molecular forms of the same gene...

Question 18

In rabbits,there are four alleles at the c locus.Arranged in dominance sequence they are C (agouti),c^ch (chinchilla),c^h (Himalayan),and c (albino) Which of the following crosses will NOT be possible?

Accepted Answer

Two agouti rabbits cannot produce chinchilla and Himalayan offspring because agouti is the dominant allele, and both parents would need to carry recessive alleles for chinchilla and Himalayan traits to appear.

Question 19

In horses,there are four alleles at the A locus.Arranged in dominance sequence,they are A (wild),aS1U1P1bS1S1P0 (bay),aS1U1P1c S1S1P0(brown),aS1U1P1dS1S1P0 (black)
If you bred several bay mares whose sires were brown to a brown stallion whose sire was black,what are the genotypes of the parents; what type of offspring would be produced; and in what proportion?

Accepted Answer

Breeding a bay mare with a brown sire to a brown stallion with a black sire would result in offspring with genotypes of a^ba^c, a^ba^d, a^ca^c, and a^ca^d. This would result in 1/2 of the offspring being bay and 1/2 being brown, with no black offspring produced.

Question 20

In mice,the allele for colored fur (C)is dominant to the allele for albinism (c).The allele for normal behavior (W)is dominant to that for waltzing movement (w).Give the probable genotypes of the parents if a colored normal crossed with a white waltzer produced 10 colored normal,8 colored waltzers,2 white waltzers,and 11 white normal.

Accepted Answer

The answer of In mice,the allele for colored fur (C)is...

Quiz 13: Observing Patterns in Inherited Traits

In tomatoes,red (R) is dominant to yellow (r) ,tall (D) is dominant to dwarf (d) ,and smooth (H) is dominant to hairy (h) .How many possible different phenotypes are there in relationship to these three characteristics?

In poultry,the genes for rose comb (R) and pea comb (P) produce walnut whenever they occur together (R P) ; single-combed individuals have the homozygous condition for both genes (rr pp) .Give the phenotypic results of a cross of Rr Pp x rr Pp

In the garden pea,Mendel found that tall ( D ) plants,green pods ( G ) ,and inflated pods ( C ) were dominant to dwarf (d ) plants,yellow pods ( g ) ,and constricted pods ( c ) . Determine the chances of producing the offspring D G cc from a cross of D d G g C c x D d G g C c.

Heritable units of information about traits are called __________.

If you were following the inheritance patterns of two different sets of multiple alleles located on different chromosomes,with locus 1 having five possible alleles and locus 2 having six alleles,there would be a total of _____ different possible gametes produced.

In sweet peas,dominant alleles C and P are necessary for colored flowers.In the absence of either ( pp or cc ) or both (cc pp) ,the flowers are white.What the phenotypic ratios be for the cross of Cc pp x cc Pp?

Different molecular forms of the same gene are __________.

In rabbits,there are four alleles at the c locus.Arranged in dominance sequence they are C (agouti) ,c^ch (chinchilla) ,c^h (Himalayan) ,and c (albino) Which of the following crosses will NOT be possible?

Quiz 13: Observing Patterns in Inherited Traits

In tomatoes,red (R) is dominant to yellow (r) ,tall (D) is dominant to dwarf (d) ,and smooth (H) is dominant to hairy (h) .How many possible different phenotypes are there in relationship to these three characteristics?

In poultry,the genes for rose comb (R) and pea comb (P) produce walnut whenever they occur together (R__ P__) ; single-combed individuals have the homozygous condition for both genes (rr pp) .Give the phenotypic results of a cross of Rr Pp x rr Pp

In the garden pea,Mendel found that tall ( D ) plants,green pods ( G ) ,and inflated pods ( C ) were dominant to dwarf (d ) plants,yellow pods ( g ) ,and constricted pods ( c ) . Determine the chances of producing the offspring D__ G__ cc from a cross of D d G g C c x D d G g C c.

Heritable units of information about traits are called __________.

If you were following the inheritance patterns of two different sets of multiple alleles located on different chromosomes,with locus 1 having five possible alleles and locus 2 having six alleles,there would be a total of _____ different possible gametes produced.

In sweet peas,dominant alleles C and P are necessary for colored flowers.In the absence of either (__ pp or cc __) or both (cc pp) ,the flowers are white.What the phenotypic ratios be for the cross of Cc pp x cc Pp?

Different molecular forms of the same gene are __________.

In rabbits,there are four alleles at the c locus.Arranged in dominance sequence they are C (agouti) ,cch (chinchilla) ,ch (Himalayan) ,and c (albino) Which of the following crosses will NOT be possible?

In poultry,the genes for rose comb (R) and pea comb (P) produce walnut whenever they occur together (R P) ; single-combed individuals have the homozygous condition for both genes (rr pp) .Give the phenotypic results of a cross of Rr Pp x rr Pp

In the garden pea,Mendel found that tall ( D ) plants,green pods ( G ) ,and inflated pods ( C ) were dominant to dwarf (d ) plants,yellow pods ( g ) ,and constricted pods ( c ) . Determine the chances of producing the offspring D G cc from a cross of D d G g C c x D d G g C c.

In sweet peas,dominant alleles C and P are necessary for colored flowers.In the absence of either ( pp or cc ) or both (cc pp) ,the flowers are white.What the phenotypic ratios be for the cross of Cc pp x cc Pp?

In rabbits,there are four alleles at the c locus.Arranged in dominance sequence they are C (agouti) ,c^ch (chinchilla) ,c^h (Himalayan) ,and c (albino) Which of the following crosses will NOT be possible?