Advantages to using the garden pea for Mendel's experiments included
all listed below except
A)true-breeding varieties were scarce.
B)he could expect to observe segregation of traits among the offspring
C)they have relatively short generation time.
D)sex organs of the pea are enclosed within the flower
Pea plants can
A)self-pollinate, but are not self-compatible
D)reproduce without pollination
In Mendel's F2 generation, one out of four plants had white flowers because
A)the trait is sex-linked
B)both parents were heterozygous purple
C)one parent was homozygous recessive
D)both parents were heterozygous white
Mendelian inheritance may be difficult to analyze because of all of the following except
A)formation of Barr bodies
Klinefelter's syndrome is caused by a nondisjunction resulting in a genotype ofA)YYYB)XYYC)XXXD)XXY
In the F2 generation, the 3:1 ratio is really a disguised
The ratio often referred to the Mendelian ratio is
When Mendel crossed pure-breeding purple and white flowered pea
plants, the dominant to recessive ratio in the F1
On which of the following chromosomes are sex-linked traits carried?
The genotype of an individual with Turner syndrome is
In Mendel's F2 generation of the purple and white flower
crossing, the dominant to recessive ratio was
The name for a chromosome map unit is
Which of the following represents a testcross?
A)Ww x WW
B)ww x WW
C)Ww x Ww
D)WW x WW
A disease caused by an autosomal primary nondisjunction is
A individual who has two of the same allele is said to be
Which of the following represents a dihybrid?
Where two alternatives for a trait are tall and short, and tall is
dominant, the genotype of a heterozygous individual would be expressed
Which of the following chromosomes, if trisomic, cause failure of
survival of development?
The appearance resulting from a given gene combination is referred to
Compared to previous geneticists, the unique characteristic of
Mendel's work was
A)keeping records of numbers of different progeny
B)choosing the garden pea for his experiment
D)studying more than one generation
E)crossing true-breeding plants
A modified Mendelian ratio is represented by
The two alternatives for a trait are red and white and red is
dominant. However, white is the most common trait. What is the
genotype of a homozygous dominant individual?
Where the two alternatives for a trait are broad and narrow, and
broad is dominant, the phenotype of a homozygous dominant individual
would be expressed as
A genetic disorder caused by a dominant allele is
Early ideas about heredity includeA)traits can be masked in some generationsB)traits were segregated among progenyC)alleles do not influence each otherD)traits are transmitted directlyE)not all copies of a factor are identical
What is the phenotype of a fruit fly whose genotype is g+g+vsvs (where g = gray body and vs = vestigial wings; wild type = black body and normal wings)?
A)gray body; vestigial wings
B)gray body; normal wings
C)black body; vestigial wings
D)black body; normal wings
In garden peas, height is determined by a single gene with tall being
dominate to short. If two heterozygous plants are crossed, what
proportion of the tall progeny will be homozygous dominant?
In the cross MMnn x mmNN, what proportion of the resulting
F1 would be homozygous dominant for both genes?
In humans pointed eyebrows are dominant to smooth eyebrows and
widow's peak (downward pointed frontal hairline) is dominant to
continuous hairline. What phenotypic ratio would you expect in the
offspring from a cross between an individual heterozygous for both
genes and an individual homozygous recessive for both genes?
Hypertrichosis, hairiness of the pinna of the ear, is inherited as a
Y-linked recessive in humans. If a man with hypertrichosis marries a
normal woman, what types of children may they have?
A)All of their children of both sexes have hypertrichosis.
B)All the sons have hypertrichosis, but none of their daughters.
C)Half of their sons, but none of their daughters will have hypertrichosis.
D)All the daughters have hypertrichosis, but none of their sons.
E)None of their children have hypertrichosis.
The model for the dihybrid cross of heterozygotes predicts a
phenotypic ratio of 9:3:3:1.
Epistasis is a genetic condition in which certain alleles of one
locus can alter the expression of alleles of a different locus.
One gene can have multiple effects on an organism.
The genotypes of a husband and wife are IAIB x
IAi. Among the blood types of their children, how many
different genotypes and phenotypes are possible?
A)2 genotypes; 3 phenotypes
B)3 genotypes; 4 phenotypes
C)4 genotypes; 4 phenotypes
D)3 genotypes; 3 phenotypes
E)4 genotypes; 3 phenotypes
A trait caused by a recessive autosomal allele will result in a pedigree that shows affected individuals having at least one affected parent.
Down syndrome results from:
A)the absence of one chromosome in position 21
B)the presence of an extra chromosome in position 21
C)the absence of both chromosomes in position 21
D)crossing over on the chromosomes in position 21
E)none of the above
Which of the following is not a result of nondisjunction of the sex chromosomes?
E)both a and b