Mastering Bio Ch 11
You cross a true-breeding red-flowered snapdragon with a true-breeding white-flowered one. All of the F1 are pink. What does this say about the potential traits?
-Pink is dominant, and red and white are recessive
-Both red and white are pleiotropic
-Red is completely dominant
-Red shows incomplete dominance over white
Red shows incomplete dominance over white
In the cross AaBbCc x AaBbCc, what is the probability of producing the genotype AABBCC?
-1/8
-1/64
-1/4
-1/16
-1/32
1/64
Quantitative characters vary in a population along a continuum. How do such characters differ from the characters investigated by Mendel in his experiments on peas?
-Environment and genes affect quantitative characters, whereas only genes determined the pea characters studied by Mendel
-Quantitative characters are due to polygenic inheritance, the additive effects of two or more genes on a single phenotype character. A single gene affected all but one of the pea characters studied by Mendel
-The nature of inheritance quantitative characters is poorly understood, and Mendel understood the nature of inheritance for the characters he studied in his peas
Quantitative characters are due to polygenic inheritance, the additive effects of two or more genes on a single phenotype character. A single gene affected all but one of the pea characters studied by Mendel
Each chromosome in this homologous pair possesses a different allele for flower color. Which statement about this homologous pair of chromosomes is correct?
-These homologous chromosomes are formed by DNA replication
-These homologous chromosomes represent a maternal and a paternal chromosome
-Each of these homologous chromosomes consists of a single chromatid. Therefore, they must come from a haploid cell.
These homologous chromosomes represent a maternal and a paternal chromosome
When a dominant allele coexists with a recessive allele in a heterozygote individual, how do they interact with each other?
-The dominant allele prevents expression of the recessive allele by an unknown mechanism
-They do not interact at all
-The dominant allele prevents transcription of the recessive allele
They do not interact at all
Which of the following statements is a correct explanation for the observation that all offspring exhibit a phenotype for a particular trait that appears to be a blend of the two parental varieties?
-The genes for the trait are dominant in both of the parents
-The genes for the trait are recessive in both of the parents
-Neither of the parental genes is dominant over the other
-The genes are linked and do not separate during meiosis
Neither of the parental genes is dominant over the other
What is the difference between heterozygous and homozygous individuals?
-All of the gametes from a homozygote carry the same version of the gene while those of a heterozygote will differ
-Homozyotes have one chromosome while heterozygotes have two similar chromosomes
-Heterozygotes carry two copies of a gene while homozygotes only carry one
-The homozygote will express the dominant trait and the heterozygote will express the recessive trait
All of the gametes from a homozygote carry the same version of the gene while those of a heterozygote will differ
When constructing a Punnett Square, the symbols on the outside of the boxes represent _____, while those inside the boxes represent _____.
-progeny, gametes
-gametes, parents
-parents, gametes
-gametes, progeny
gametes, progeny
True or False? The same phenotype can be produced by more than one genotype.
True
True or False? In diploid organisms, a dominant phenotype will only be expressed if the individual is homozygous dominant for that trait.
False
Two mice are heterozygous for albinism (Aa). The dominant allele (A) codes for normal pigmentation, and the recessive allele, (a), codes for no pigmentation. What percentage of their offspring would have been an albino phenotype?
-100
-75
-50
-25
25%
A tall, purple-flowered pea plant (TtPp) is allowed to self-pollinate. (The recessive allele code for short plants and white flowers.) The phenotypic ratio of the resulting offspring is 9:3:3:1. What is the genotype of the plant whose phenotype appeared once out of every 16 offspring (the "1" in the 9:3:3:1 ratio)
-TtPp
-TTPP
-TTpp
-ttpp
ttpp