A chromosome with two arms of equal length is referred to as
D. metacentric
If yellow and round phenotypes phenotypes in peas are dominant, you know the genotype of all peas that are green and wrinkled
a. True
b. False
a. True
Environmental conditions that allow conditional lethals to live are known as ____ conditions.
A. permissive
Which of the following ratios show incomplete dominance?
A. 1:2:1
Monohybrid crosses helped reveal the Law of Independent Assortment.
a. True
b. False
b. False
The oldest known living organism on the planet are the
A. prokaryotes
The ____ is a Mendelian law that states that both alleles must separate during gamete formation.
A. Law of Segregation
What aspects of chromosome behavior most clearly accounts for Mendel's law of segregation?
D. movement of homologous chromosomes to opposite poles at anaphase I of meiosis
What does a diamond symbol (<>) on a pedigree chart indicate?
C. unspecified gender
An interaction between non-allelic genes that result in the masking of expression of a phenotype
B. epistasis
A person who has type O blood has
D. both anti-A and anti-B antibodies
The stage of mitosis when chromosomes condense to form rod-shaped structures visible under the microscope is
C. prophase
During which of the following stages of the cell cycle would a chromosome consist of only a single chromatid?
a. G1
2. G2
c. mitotic prophase
d. mitotis metaphase
e. All of the above
a. G1
An allele that expresses its phenotype even when heterozygous with a recessive allele is termed
D. dominant
At which of the following stages of meiosis would homologous chromosomes be paired?
E. both prophase and metaphase of meiosis I
_____ is the process in which both egg and pollen come from the same plant.
A. self-fertilization
Currently, the estimated number of genes in the human genome is
A. 20,000 to 30,000
In some genetically enginerred corn plants the dominant gene (BT) produces a protein that is lethal to certain flying insect pests that eat the corn plants. It was also found that the pollen could cause death in some flying insects. If the corn plant is heterozygous for BT, what proportion of the pollen would carry the dominant gene?
C. 1/2
In a monohybrid cross between an organism that is homozygous dominant and an organism that is homozygous recessive, what proportion of heterozygotes is expected among the F2 offspring?
E. 1/2
Cross-fertilization is the same as reciprocal cross.
a. True
b. False
b. False
In which condition is neither gene fully expressed?
B. incomplete dominance
The first offspring from the parents are called
A. F1
In Drosophila virilis, nuclei of somatic cells contain 12 chromosomes while nuclei of sperm cells contain only 6 chromosomes. What does "n" equal for this species?
C. 6
Which of the following ratios indicates a recessive lethal gene?
B. 2:1
The snapdragon flower colors white, pink, and red indicate codominant inheritance.
a. True
b. False
b. False
During which of the following stages of the cell cycle would a chromosome consist of only a single chromatid?
A. G1
An individual can be a heterozygote for one trait and a homozygote for another.
a. True
b. False
a. True
Blood type "AB" is an example of
B. codominance
In codominance, F1 hybrids show the traits of both parents.
a. True
b. False
a. True
Which aspects of chromosome behavior is/are primarrily responsible for the tremendous amount of genetic variability associated with sexual reproduction?
E. both crossing over between homologous chromosomes during prophase I of meiosis and independent alignment of different homologous pairs on the metaphase I spindle contribute to genetic variability
Which of the following was probably the first genetic material on earth?
D. RNA
A _____ is a cross between an unknown and a homozygous recessive.
C. testcross
Cells in the G2 stage of the cell cycle have ____ as cells of the same species in the G1 stage.
B. twice as many chromatids
_____,_____, and ____ were all involved in the rediscovery of Mendel's research.
C. Erich von Tschermak, Carl Correns, and Hugo de Vries
A YY or yy genotype is called heterozygous.
a. True
b. False
b. False
When a late blooming pea and an early blooming pea are crossed and an intermediate phenotype occurs, this result would suggest incomplete dominant inheritance.
a. True
b. False
a. True
Mitosis results in ____ chromosome number, whereas meiosis results in _____ chromosome number.
B. no change in, a reduction by half in
An alternative form of a single gene is known as
B. allele
A rare recessive trait in a pedigree is indicated by which pattern of inheritance?
B. horizontal
What aspect of chromosome behavior most clearly accounts for Mendel's law of independent assortment?
B. crossing over between homologous chromosomes during prophase I of meiosis
Duplications of the genes, followed by mutation, is responsible for the formation of