Question 1

Alternative forms of a gene that influence the same trait and are found at the same location in homologous chromosomes are called

Accepted Answer

Alternative forms of a gene are called alleles. They can be located at the same location in homologous chromosomes and influence the same trait. Phenotypes are the physical manifestation of the genotype, and genotypes refer to the genetic makeup of an individual. Codominance and incomplete dominance refer to specific patterns of inheritance and are not synonymous with the concept of alleles.

Question 2

What will the genotypic ratio be of a monohybrid cross of two individuals who are both heterozygous for a trait?

Accepted Answer

When both parents are heterozygous (Aa x Aa), the resulting genotypic ratio will be 1:2:1, meaning 25% of the offspring will be homozygous dominant (AA), 50% will be heterozygous (Aa), and 25% will be homozygous recessive (aa). Therefore, the correct answer is D.

Question 3

Mendel carried out most of his research with

Accepted Answer

Mendel carried out most of his research with pea plants.

Question 4

What are alleles?

Accepted Answer

Alleles are alternative forms of a single gene that code for different versions of a particular trait, such as eye color or hair color. For example, the gene for eye color may have two alleles - one for blue eyes and one for brown eyes. These alleles may interact in different ways to produce varying phenotypes.

Question 5

In humans,brown eyes (B)is a simple dominant trait over blue eyes (b).What is the genotype of a brown-eyed woman who has a blue-eyed child?

Accepted Answer

The brown-eyed woman must be heterozygous (Bb) because she has one dominant allele for brown eyes and one recessive allele for blue eyes. The only way for her to have a blue-eyed child is if she passes down the recessive blue-eyed allele to her child. The child must be homozygous recessive (bb) because they have two copies of the blue-eyed allele.

Question 6

The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability.The standard assumption is that tongue-rolling is a dominant allele at a single gene locus.Which of the following would cast doubt on this assumption?

Accepted Answer

The assumption that tongue-rolling is a dominant allele at a single gene locus would be cast into doubt if a student who can roll his tongue has a mother and father, both of whom cannot roll their tongues AND with very little effort the non-tongue-rollers can learn to roll their tongues. This would suggest that tongue-rolling is not a purely genetic trait, but rather a learned behavior.

Question 7

If you were to breed a black male guinea pig to a brown female guinea pig in an attempt to determine which one was homozygous dominant and which one was homozygous recessive,how could you be certain that the guinea pigs are truly homozygous?

Accepted Answer

Breeding the guinea pigs for many generations and consistently producing offspring with the same coat color would indicate that the guinea pigs are homozygous for that trait. This is because, after many generations of breeding, any heterozygous individuals would have produced both dominant and recessive offspring, resulting in a mix of coat colors in their descendants. Therefore, a consistent coat color in the offspring over many generations would suggest that the parents are homozygous. The other options do not provide as strong of evidence for homozygosity.

Question 8

In peas,yellow is dominant over green in seeds.With which of these is it best to cross a yellow-seeded pea plant to determine whether it is homozygous or heterozygous?

Accepted Answer

Crossing with a green-seeded plant (recessive) will reveal if the yellow-seeded plant is homozygous (all offspring yellow) or heterozygous (some offspring green).

Question 9

In which kind of cross would you expect to find a phenotypic ratio of 3:1 among the F₂ offspring?

Accepted Answer

A 3:1 phenotypic ratio in the F2 generation is typical of a monohybrid cross involving a single gene with two alleles, where one allele is dominant and the other is recessive.

Question 10

If an organism shows a recessive phenotype,such as short pea plants,its genotype can be

Accepted Answer

A recessive phenotype can only be expressed if an individual is homozygous recessive, meaning it has two copies of the recessive allele. Therefore, the genotype must be tt in order to show the short pea plant phenotype.

Question 11

Tay-Sachs is a recessive genetic disease in humans.If one parent is homozygous normal and the other is a carrier (heterozygous),what are the chances that their child will have this disease?

Accepted Answer

Since Tay-Sachs disease is recessive, a child must inherit two copies of the defective gene to exhibit the disease. If one parent is homozygous normal (not carrying the disease allele) and the other is a carrier (heterozygous, with one normal and one disease allele), all children will receive one normal allele from the homozygous parent, preventing the disease.

Question 12

For Mendel's law of segregation to occur,the alleles must be

Accepted Answer

Mendel's law of segregation occurs when two alleles of a gene are on a homologous pair of chromosomes at the same loci. During meiosis, these two alleles will separate and end up in different gametes, resulting in offspring that inherit one allele from each parent.

Question 13

Which is NOT true according to Mendel's law of segregation?

Accepted Answer

The answer of Which is NOT true according to Mendel's...

Question 14

Mendel's law of segregation implies that the two members of an allele pair

Accepted Answer

Mendel's law of segregation states that the two members of an allele pair (e.g. Tt) separate or segregate from each other during the formation of gametes (e.g. T or t in different gametes). This leads to the production of gametes with one allele from the pair, which can then combine with gametes from another parent to produce offspring with different allele combinations. Option B is not correct because if the members of an allele pair were distributed to the same gamete, there would be no segregation and no variation in offspring. Option C is not correct because the alleles are assorted independently, not dependently. Option D is not entirely accurate as the law does not require pairwise segregation but segregation of the two members of an allele pair. Option E is incorrect because the two members of an allele pair can code for different traits or features.

Question 15

Which of the following represents the physical characteristics of the individual?

Accepted Answer

Phenotype refers to the physical characteristics of an individual, such as their hair or eye color. Genotype (B) refers to an individual's genetic makeup, while alleles (C) are different versions of a gene. Homozygous (D) refers to an individual having two identical alleles for a particular gene, while dominance (E) refers to one allele being expressed over another in determining a phenotype.

Question 16

In a Mendelian monohybrid cross involving two homozygous genotypes,the ____ generation is always completely heterozygous.

Accepted Answer

In a Mendelian monohybrid cross involving two homozygous genotypes, the F₁ generation is always completely heterozygous. This is because the F₁ generation is the result of crossing two homozygous parents, each of which contributes one allele to the offspring. Since the parents are homozygous, they can only contribute one type of allele, and the offspring will therefore be heterozygous for that gene.

Question 17

If you had a black male guinea pig and brown female guinea pig,but you didn't know which was the dominant characteristic,how would you find out the dominant color,assuming the dominant characteristic is homozygous,?

Accepted Answer

If the dominant characteristic is homozygous, mating the black male and brown female will result in offspring that display the dominant color.

Question 18

In a testcross,an organism with a dominant phenotype,but unknown genotype is crossed with which of the following to establish its genotype?

Accepted Answer

In a testcross, the best choice to establish the genotype of an organism with a dominant phenotype, but unknown genotype, is to cross it with a homozygous recessive individual. This is because the offspring resulting from this cross will all show the dominant phenotype if the unknown organism is homozygous dominant or heterozygous, but only half of them will show the dominant phenotype if the unknown organism is heterozygous. By analyzing the phenotypic ratios of the offspring, we can determine the genotype of the unknown organism.

Question 19

In humans,widow's peak (W)is dominant over straight hairline (w).If a heterozygous male marries a female with a straight hairline,what percent of their children can be expected to have widow's peak?

Accepted Answer

The heterozygous male is represented as Ww and the female with straight hairline is represented as ww. Therefore, their possible genotypes of the offspring are WW, Ww, Ww, and ww. The only possible genotype for having a straight hairline is ww. Therefore, only 50% of their children can be expected to have widow's peak (Ww and WW).

Question 20

The _____ indicates the gene combination of an individual.

Accepted Answer

The genotype refers to the genetic makeup or gene combination of an individual. Phenotype refers to the physical and observable traits, loci refer to the specific location of a gene on a chromosome, dominance describes the relationship between different alleles, and homozygous describes having two identical alleles for a particular gene.

Quiz 23: Patterns of Gene Inheritance

Alternative forms of a gene that influence the same trait and are found at the same location in homologous chromosomes are called

What will the genotypic ratio be of a monohybrid cross of two individuals who are both heterozygous for a trait?

Mendel carried out most of his research with

What are alleles?

In humans,brown eyes (B) is a simple dominant trait over blue eyes (b) .What is the genotype of a brown-eyed woman who has a blue-eyed child?

The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability.The standard assumption is that tongue-rolling is a dominant allele at a single gene locus.Which of the following would cast doubt on this assumption?

If you were to breed a black male guinea pig to a brown female guinea pig in an attempt to determine which one was homozygous dominant and which one was homozygous recessive,how could you be certain that the guinea pigs are truly homozygous?

In peas,yellow is dominant over green in seeds.With which of these is it best to cross a yellow-seeded pea plant to determine whether it is homozygous or heterozygous?

In which kind of cross would you expect to find a phenotypic ratio of 3:1 among the F₂ offspring?

If an organism shows a recessive phenotype,such as short pea plants,its genotype can be

Tay-Sachs is a recessive genetic disease in humans.If one parent is homozygous normal and the other is a carrier (heterozygous) ,what are the chances that their child will have this disease?

For Mendel's law of segregation to occur,the alleles must be

Which is NOT true according to Mendel's law of segregation?

Mendel's law of segregation implies that the two members of an allele pair

Which of the following represents the physical characteristics of the individual?

In a Mendelian monohybrid cross involving two homozygous genotypes,the ____ generation is always completely heterozygous.

If you had a black male guinea pig and brown female guinea pig,but you didn't know which was the dominant characteristic,how would you find out the dominant color,assuming the dominant characteristic is homozygous,?

In a testcross,an organism with a dominant phenotype,but unknown genotype is crossed with which of the following to establish its genotype?

In humans,widow's peak (W) is dominant over straight hairline (w) .If a heterozygous male marries a female with a straight hairline,what percent of their children can be expected to have widow's peak?

The _____ indicates the gene combination of an individual.

Quiz 23: Patterns of Gene Inheritance

Alternative forms of a gene that influence the same trait and are found at the same location in homologous chromosomes are called

What will the genotypic ratio be of a monohybrid cross of two individuals who are both heterozygous for a trait?

Mendel carried out most of his research with

What are alleles?

In humans,brown eyes (B) is a simple dominant trait over blue eyes (b) .What is the genotype of a brown-eyed woman who has a blue-eyed child?

The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability.The standard assumption is that tongue-rolling is a dominant allele at a single gene locus.Which of the following would cast doubt on this assumption?

If you were to breed a black male guinea pig to a brown female guinea pig in an attempt to determine which one was homozygous dominant and which one was homozygous recessive,how could you be certain that the guinea pigs are truly homozygous?

In peas,yellow is dominant over green in seeds.With which of these is it best to cross a yellow-seeded pea plant to determine whether it is homozygous or heterozygous?

In which kind of cross would you expect to find a phenotypic ratio of 3:1 among the F2 offspring?

If an organism shows a recessive phenotype,such as short pea plants,its genotype can be

Tay-Sachs is a recessive genetic disease in humans.If one parent is homozygous normal and the other is a carrier (heterozygous) ,what are the chances that their child will have this disease?

For Mendel's law of segregation to occur,the alleles must be

Which is NOT true according to Mendel's law of segregation?

Mendel's law of segregation implies that the two members of an allele pair

Which of the following represents the physical characteristics of the individual?

In a Mendelian monohybrid cross involving two homozygous genotypes,the ____ generation is always completely heterozygous.

If you had a black male guinea pig and brown female guinea pig,but you didn't know which was the dominant characteristic,how would you find out the dominant color,assuming the dominant characteristic is homozygous,?

In a testcross,an organism with a dominant phenotype,but unknown genotype is crossed with which of the following to establish its genotype?

In humans,widow's peak (W) is dominant over straight hairline (w) .If a heterozygous male marries a female with a straight hairline,what percent of their children can be expected to have widow's peak?

The _____ indicates the gene combination of an individual.

In which kind of cross would you expect to find a phenotypic ratio of 3:1 among the F₂ offspring?