Section 1
Preview this deck
In carrying out his breeding studies, Mendel examined characters that had which of the following properties? (eText Concept 14.1) They were controlled by loci that were (or behaved as if they were) on different chromosomes. It was possible to isolate true-breeding varieties for each trait. The traits varied in an either-or fashion. The characters each were controlled by a single gene. All of the listed responses are correct.
Front
| 5 | 0 | ||
| 4 | 0 | ||
| 3 | 0 | ||
| 2 | 0 | ||
| 1 | 0 |
Active users
0
All-time users
0
Favorites
0
Last updated
6 years ago
Date created
Mar 14, 2020
Cards (97)
Section 1
(50 cards)
In carrying out his breeding studies, Mendel examined characters that had which of the following properties? (eText Concept 14.1) They were controlled by loci that were (or behaved as if they were) on different chromosomes. It was possible to isolate true-breeding varieties for each trait. The traits varied in an either-or fashion. The characters each were controlled by a single gene. All of the listed responses are correct.
All of the listed responses are correct.
Trait
One of two or more detectable variants in a genetic character.
Pea plants are tall if they have the genotype TT or Tt, and they are short if they have genotype tt. A tall plant is mated with a short plant. Which outcome below would indicate that the tall parent plant was heterozygous? (eText Concept 14.1) All of the offspring are short. All of the offspring are tall. The ratio of tall offspring to short offspring is 3:1. The ratio of tall offspring to short offspring is 1:1. There is not enough information to answer the question.
The ratio of tall offspring to short offspring is 1:1.
Phenotype
Expressed. The observable physical and physiological traits of an organism, which are determined by its genetic makeup.
A = big apples; R = red apples; a = small apples; r = yellow apples. You have one tree that produces big yellow apples and another tree that produces small red apples. When the two are crossed, you find that half of the new trees produce big red apples and half produce big yellow apples. What are the genotypes of the parents? (eText Concept 14.1) AArr and aaRr Aarr and aaRr AARr and Aarr AaRr and AaRr AaRr and aarr
AArr and aaRr
Concept Check 14.1 What if? List all gametes that could be made by a pea plant heterozygous for seed color, seed shape, and pod shape (YyRrIi; see Table 14.1). How large a Punnett square would you need to draw to predict the offspring of a self-pollination of this trihybrid?
See table
Concept 14.3 Inheritance Patterns are often more complex than predicted by simple Mendelian Genetics
...
Recessive Allele
An allele whose phenotypic effect is not observed in a heterozygote.
If an organism that is homozygous dominant is crossed with a heterozygote for that trait, the offspring will be _____. (eText Concept 14.1) all of the dominant phenotype 1/4 of the recessive phenotype all homozygous dominant all homozygous recessive present in a 9:3:3:1 ratio
All of the dominant phenotype
The Law of Independent Assortment
Mendel's second law, stating that each pair of alleles segregates, or assorts, independently of each other pair during gamete formation; applies when genes for two characters are located on different pairs of homologous chromosomes or when they are far enough apart on the same chromosome to behave as though they are on different chromosomes.
Which choice below is a basic difference between Mendel's particulate hypothesis and the hypothesis of blending inheritance? (eText Concept 14.1) The blending inheritance hypothesis, but not the particulate hypothesis, maintained that mutation is the major source of new gene combinations. The blending inheritance hypothesis, but not the particulate hypothesis, maintained that the two alleles at any given locus are always different. The blending inheritance hypothesis, but not the particulate hypothesis, maintained that the traits governed by genes in the egg are different from the traits governed by genes in the sperm. The blending inheritance hypothesis, but not the particulate hypothesis, maintained that after a mating, the genetic material provided by each of the two parents is mixed in the offspring, losing its individual identity. All of the listed responses are correct.
The blending inheritance hypothesis, but not the particulate hypothesis, maintained that after a mating, the genetic material provided by each of the two parents is mixed in the offspring, losing its individual identity. The blending hypothesis maintained that the genetic material contributed by the two parents mixes in a manner analogous to the way blue and yellow paints blend to make green.
Complete dominance
The situation in which the phenotypes of the heterozygote and dominant homozygote are indistinguishable.
Monohybrid Cross
A cross between two organisms that are heterozygous for the character being followed (or the self-pollination of a heterozygous plant).
The Law of Segregation
Mendel's first law, stating that the two alleles in a pair segregate (separate from each other) into different gametes during gamete formation.
Heterozygous
Having two different alleles for a given gene.
P Generation
The true-breeding (homozygous) parent individuals from which F1 hybrid offspring are derived in studies of inheritance; P stands for "parental."
Concept Check 14.1 Make Connections. In some pea plant crosses, the plants are self-pollinated. Refer back to Concept 13.1 (pp. 248-249) and explain whether self-pollination is considered asexual or sexual reproduction.
Asexual
The F1 generation differed from the F2 in Mendel's experiments in that _____. (eText Concept 14.1) all of the F1 showed the dominant phenotype, whereas only half of the F2 did all of the F1 showed the dominant phenotype, but only three-fourths of the F2 did all of the F1 showed the dominant phenotype, and all of the F2 showed the recessive phenotype one-half of the F1 showed the dominant phenotype, and three-fourths of the F2 did none of the F1 showed the dominant phenotype, but one-half of the F2 did
all of the F1 showed the dominant phenotype, but only three-fourths of the F2 did
F2 generation
The offspring resulting from interbreeding (or self-pollination) of the hybrid FF1 generation.
The law of independent assortment _____. (eText Concept 14.1) states that the alleles at different loci segregate independently from one another during a dihybrid cross can account for a 9:3:3:1 ratio seen in the F2 generation applies only to genes that are present on different chromosomes (or behave as if they were) The first and second answers are correct. The first, second, and third answers are correct.
The first, second, and third answers are correct.
Genotype
The genetic makeup, or set of alleles, of an organism.
In a certain plant, the alleles A, B, and C are completely dominant to the alleles a, b, and c. A plant with the genotype AABbcc will have the same phenotype as a plant with the genotype _____. (eText Concept 14.1) Aabbcc aabbcc AaBBcc AABBCc None of the listed responses is correct.
AaBBcc
Homozygous
Having two identical alleles for a given gene.
The multiplication rule
A rule of probability stating that the probability of two or more independent events occurring together can be determined by multiplying their individual probabilities.
The addition rule
A rule of probability stating that the probability of any one of two or more mutually exclusive events occurring can be determined by adding their individual probabilities.
What is indicated when a single-character testcross yields offspring that all have the dominant phenotype? (eText Concept 14.1) The parent with the dominant phenotype was homozygous. The parent with the dominant phenotype was heterozygous. Epistasis has occurred. The alleles are codominant. Both parents are heterozygous.
The parent with the dominant phenotype was homozygous.
If a plant variety is true-breeding for a dominant trait, then _____. (eText Concept 14.1) if the plant were allowed to self-pollinate, the dominant and recessive traits would consistently appear in a 3:1 ratio among the progeny the plant is heterozygous for the trait if the plant were crossed with a heterozygote, one-half of the progeny would show the dominant trait, and one-half would show the recessive trait if the plant were allowed to self-pollinate, all of the progeny would have the dominant trait the variety is unable to mutate
if the plant were allowed to self-pollinate, all of the progeny would have the dominant trait
Allele
Any of the alternative versions of a gene that may produce distinguishable phenotypic effects.
Phenotype
The EXPRESSED/observable physical and physiological traits of an organism, which are determined by its genetic makeup.
What is Mendel's Second Law?
The Law of Independent Assortment. Mendel's second law, stating that each pair of alleles segregates, or assorts, independently of each other pair during gamete formation; applies when genes for two characters are located on different pairs of homologous chromosomes or when they are far enough apart on the same chromosome to behave as though they are on different chromosomes.
The Law of segregation
Mendel's first law, stating that the two alleles in a pair segregate (separate from each other) into different gametes during gamete formation.
Physically, what are different alleles? (eText Concept 14.1) Different alleles are different DNA sequences found at the same locus on sister chromatids. Different alleles are different particles found in gametes. Different alleles are different phenotypes for a particular character. Different alleles are different DNA sequences found at the same locus on homologous chromosomes. None of the listed responses is correct.
Different alleles are different DNA sequences found at the same locus on homologous chromosomes.
Dihybrid Cross
A cross between two organisms that are each heterozygous for both of the characters being followed (or the self-pollination of a plant that is heterozygous for both characters).
F1 generation
The first filial, hybrid (heterozygous) offspring arising from a parental (P generation) cross.
Concept 14.2 The laws of probability govern Mendelian Inheritance
...
Homologous pairs of chromosomes often _____. (eText Concept 14.1) carry different genes for different traits differ in length contain different alleles are not both present in diploid somatic cells are paired up in the G2 phase of the cell cycle
contain different alleles
Character
An observable heritable feature that may vary among individuals.
Dihybrids
An organism that is heterozygous with respect to two genes of interest. All the offspring from a cross between parents doubly homozygous for different alleles are dihybrids. For example, parents of genotypes AABB and aabb produce a dihybrid of genotype AaBb.
Concept Check 14.1 Draw It. Pea Plants heterozygous for flower position and stem length (AaTt) are allowed to self pollinate, and 400 of the resulting seeds are planted. Draw a Punnett square for this cross. How many offspring would be predicted to have terminal flowers and be dwarf? (See Table 14.1)
refer to diagram
hybridization
In genetics, the mating, or crossing, of two true-breeding varieties.
True-Breeding
Referring to organisms that produce offspring of the same variety over many generations of self-pollination.
In Mendel's monohybrid cross of purple-flowered and white-flowered peas, all members of the F1 generation had the _____ phenotype because their genotype was _____ at the flower-color locus. (eText Concept 14.1) white-flowered ... homozygous recessive white-flowered ... heterozygous purple-flowered ... homozygous recessive purple-flowered ... homozygous dominant purple-flowered ... heterozygous
purple-flowered ... heterozygous
Monohybrids
An organism that is heterozygous with respect to a single gene of interest. All the offspring from a cross between parents homozygous for different alleles are monohybrids. For example, parents of genotypes AA and aa produce a monohybrid of genotype Aa.
Concept 14.1 Mendel used the scientific approach to identify two laws of Inheritance
The Law of Segregation The Law of Independent Assortment
Genotype
The genetic makeup, or set of alleles, of an organism.
Assume tall (T) is completely dominant to dwarf (t) in a certain species of plant. If a homozygous dominant individual is crossed with a homozygous dwarf, the offspring will _____. (eText Concept 14.1) all be intermediate in height all be tall be 1/2 tall and 1/2 dwarf be 3/4 tall and 1/4 dwarf all be short
all be tall
Punnett Square
A diagram used in the study of inheritance to show the predicted genotypic results of random fertilization in genetic crosses between individuals of known genotype.
If the two traits that Mendel looked at in his dihybrid cross of smooth yellow peas with wrinkled green peas had been controlled by genes that were located near each other on the same chromosome, then the F2 generation _____. (eText Concept 14.1) would have contained four phenotypes in a 9:3:3:1 ratio would have contained only individuals that were heterozygous at both loci would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment would have contained no individuals that were heterozygous at both loci None of the listed responses is correct.
Would have deviated from the 9:3:3:1 phenotypic ratio that is predicted by the law of independent assortment If the two characters are located on the same chromosome, they will not segregate independently.
Testcross
Breeding an organism of unknown genotype with a homozygous recessive individual to determine the unknown genotype. The ratio of phenotypes in the offspring reveals the unknown genotype.
Dominant Allele
An allele that is fully expressed in the phenotype of a heterozygote.
Section 2
(47 cards)