Genetics Exam 1
In a population, there can be ____ allele(s) of a given single-copy nuclear gene
many
In pet rabbits, brown coat color is recessive to brown coat color. A black female rabbit gave birth to four black coated and three brown coated baby rabbits. What can be deduced about the genotype of the baby rabbits' father?
He could be either heterozygous black or homozygous brown
A leucine-requiring mutant strain of haploid yeast is crossed to a cysteine-requiring mutant strain. Assuming independent assortment, what proportion of the spores produced will be mutant?
3/4
What is the probability that individual A is heterozygous with respect to the condition depicted in the pedigree?
100%
A human disease associated with dysfunction of mitochondria, which results from a mutation in a single autosomal gene locus in nuclear DNA, is most likely to:
Show Mendelian inheritance patterns
Which of the following is not a classification of proteins?
Polypeptide
What type of inheritance pattern is depicted in the pedigree below?
sex-linked recessive
If a plant of genotype A/a is selfed and numerous offsprings are scored, what proportion of the progeny is expected to have the homozygous genotypes?
50%
Meiosis I is about to start in a cell of a plant in which 2n=18. At this stage, the cell has
18 chromosomes and a total of 36 chromatids
Hybrid vigor is best described as
The superiority of a heterozygous organism in which two pure lines have been crossed
Which of the following is true with respect to haploid and diploid cells?
In diploid cells, meiosis I results in the formation of haploid cells
An example of an epigenetic change is
A chemical modification of the DNA
Beside DNA, which of tghe following are major components of chromatin?
Proteins
The production of new allelic combination of two or more loci in which this individual is not like either parent, but rather a combination of both is termed
recombination
DNA found in mitochondria and chloroplasts is termed
extranuclear
If a dihybrid plant is selfed, what us the expected phenotypic ratio for two independently sorting genes? Assume H=hairy, h=smooth; R=round leaves; r=oval, elongated leaves
9:3:3:1
When a woman is injected with a fertilized egg in vitro, the probability of it successfully implanting is 20%. If a woman is injected with 5 eggs simultaneously, what is the probability that she will become pregnant?
0.672
A plant is heterozygous at three loci and homozygous recessive at 2 loci. How many different gamete genotypes can it theoretically produce in respect to these 5 loci>
8
The nuclear genome of a mouse nerve cell is compared to that of a mouse skin cell. What differences can we ex[pect to see between these two cells' nuclear genomes?
the two cells have the same genome; there will be no differences-- DIFFERENT EXPRESSION
What process during meiosis ensures independent assortment?
A corn plant of genotype Aa/BB/Cc/Dd/Ee/ff/Gg is testcrossed. What is the probability of producing a completely homozygous individual out of all offspring?
0
A biological assay using DNA to probe a membrane in which RNA is bound is referred to as a
Northern blot
A histone is composed of ___ proteins with DNA wrapped around it
8
Experiments where researchers knock out a target gene in a model organism and analyze the effect of this manipulation to get clues regarding the function of the target gene are examples of
reverse genetics
Which of the following statements is true?
Environment can influence both genotype and phenotype
If the X^2 value is calculated to be 17.01 with 9 dfm what is the approximate probability value?
0.05 < p < 0.025 ---> reject this hypothesis
Assume that diploid plant A has a cytoplasm genetically different from that of plant B. To study nuclear-cytoplasmic relations you wish to obtain a plant with the cytoplasm of plant A and the nuclear genome of predominantly plant B. How would you go about producing such a plant?
To produce a plant with cytoplasm of DNA, Plant A has to be the female. This is because the mother passes down more chloroplasts and mitochondria compared to the father. Plant B must be the male because it provides the nuclear genome.
Arabidopsis thaliana is a diploid plant model organism with 2n=10.
How many copies of each gene does each Arabidopsis thaliana cell have?
2
Arabidopsis thaliana is a diploid plant model organism with 2n=10.
How many sets of chromosomes does the nucleus of an Arabidopsis thaliana leaf cell contain?
5
Arabidopsis thaliana is a diploid plant model organism with 2n=10.
How many pairs of homologous chromosomes does the nucleus of an Arabidopsis thaliana leaf cell contain?
5
A young woman is worried about having a child because her mother's only sister had a son with Duchenne muscular dystrophy (DMD). The young woman has no brothers or sisters. (DMD is a rare X-linked recessive disorder.)
Draw the relevant parts of the pedigree of the family described below. (Be sure to include the grandmother the three women mentioned, and all their mates.)
A young woman is worried about having a child because her mother's only sister had a son with Duchenne muscular dystrophy (DMD). The young woman has no brothers or sisters. (DMD is a rare X-linked recessive disorder.)
State the most likely genotype of everyone in the pedigree.
A young woman is worried about having a child because her mother's only sister had a son with Duchenne muscular dystrophy (DMD). The young woman has no brothers or sisters. (DMD is a rare X-linked recessive disorder.)
Calculate the probability that the young woman's first child will have DMD assuming she marries a normal man with no family history of DMD.
In cats, extra toes is dominant to five toes (normal) and long tails are dominant to stub tails. A heterozygous six toes, heterozygous long-tailed cat breeds with a five toed, stub tailed cat. What proportion of the kittens will have five toes and long tails?