Chapter 9 reveiw
You conduct a dihybrid cross. A ________ ratio would make you suspect that the genes are linked. - 9:3:3:1 - 3:1 - 12:1:1:4 - 1:1:1:1
12:1:1:4
If A is dominant to a and B is dominant to b, what is the expected phenotypic ratio of the cross AaBb × AaBb? - 9:3:3:1 - 16:0:0:0 - 1:1:1:1 - 8:4:2:2
9:3:3:1
The expression of both alleles for a trait in a heterozygous individual illustrates - pleiotropy. - codominance. - polygenic inheritance.
Codominance
Shown here is a representation of a portion of a pair of homologous chromosomes. Crossing over would probably be most frequent between - hair and eyes. - eyes and legs. - eyes and arms. - hair and legs.
Hair and legs
Genes located close together on the same chromosomes are referred to as ________ genes and generally ________. - linked; do not sort independently during meiosis - homologous; are inherited together - codependent; do not sort independently during meiosis - linked; sort independently during meiosis
Linked; do not sort independently during meiosis
All the offspring of a cross between a black-eyed Mendelian and an orange-eyed Mendelian have black eyes. What is the expected phenotypic ratio of a cross between two orange-eyed Mendelians? - 1 black-eyed:3 orange-eyed - 3 black-eyed:1 orange-eyed - 0 black-eyed:1 orange-eyed - 1 black-eyed:0 orange-eyed
0 black-eyed: 1 orange-eyed
Justin has type A blood and his wife Brittany has type B blood. Justin's parents both have type AB blood, and Brittany's parents also both have type AB blood. What are the chances that Justin and Brittany's son Theodore has type A blood? - 100% - 0% - 25% - 75%
0%
Suppose that an elephant with the genotype EEFfggHh reproduces with an elephant with the genotype eeFFGgHh. What is the probability that a baby elephant (called a calf) would have the genotype EeFFGghh? - 1/256 - 1/16 - 1/64 - 1/32
1/16
Using a six-sided die, what is the probability of rolling either a 5 or a 6? - 1/6 + 1/6 = 2/3 - 1/6 × 1/6 = 1/36 - 1/6 + 1/6 = 1/3
1/6 + 1/6 = 1/3
The phenotypic ratio resulting from a dihybrid cross of two heterozygote individuals showing independent assortment is expected to be - 3:1. - 9:1:1:3. - 9:3:3:1. - 1:2:1.
1:2:1
Assuming that the probability of having a female child is 50% and the probability of having a male child is also 50%, what is the probability that a couple's first-born child will be female and that their second-born child will be male? - 50% - 20% - 25% - 75%
25%
After reading the paragraphs below, answer the questions that follow. During a summer study abroad program, you traveled to Austria to study genetics at the University of Vienna. While you were there, a momentous discovery was made: Some of Gregor Mendel's original lab books and notes were found to be buried outside of the abbey where he lived. It just so happened that the professor you were working with obtained copies of these notes and enlisted your help to decipher them. You hired a translator to translate Mendel's notes from Czech to English, and using your knowledge of modern genetics (which Mendel did not have!) you were able to construct a partial Punnett square for crosses with peas (shown here). Because the notebook was damaged from being buried for so long, this is the only information that you have regarding a cross that Mendel must have performed. Your professor has tasked you with figuring out more about this experiment. In pea plants, round peas are dominant (R) and shriveled peas are recessive (r), and yellow peas (shown as light gray in the Punnett square) are dominant (Y) and green peas (dark gray) are recessive (y). Using this information and the partial Punnett square shown, what is the phenotypic ratio of the offspring pea plants in this Punnett square? - 12:1:1:4 - 3:3:1:1 - 9:3:3:1 - 1:1:1:1
3:3:1:1
After reading the paragraphs below, answer the questions that follow. Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But some cats express the dominant phenotype for polydactyly, which results in the development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes and is recognized by the Guinness Book of World Records as the cat with the most toes. Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The total number of toes on each kitten ranges from 21 to 25. One of Jake and Lucy's kittens mates with another cat that has 18 total toes. What is the probability that one of their offspring would have 18 total toes? - 75% - 50% - 100% - 0%
50%
According to scientists, about what percentage of men currently living in Central Asia may be descended from the Mongolian ruler Genghis Khan? - 25% - 8% - 40% - 4%
8%
A testcross is - a mating between two individuals heterozygous for the trait of interest. - a mating between an individual of unknown genotype and an individual heterozygous for the trait of interest. - a mating between an individual of unknown genotype and an individual homozygous recessive for the trait of interest. - a mating between two individuals of unknown genotype.
A mating between an individual of unknown genotype and an individual homozygous recessive for the trait of interest
After reading the paragraphs below, answer the questions that follow. Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But some cats express the dominant phenotype for polydactyly, which results in the development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes and is recognized by the Guinness Book of World Records as the cat with the most toes. Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The total number of toes on each kitten ranges from 21 to 25. Along with having a variable number of toes, some kittens from Jake and Lucy's litter had a white spot on their nose. In fact, out of the 16 kittens, all 10 males had the white spot, but none of the 6 females had the white spot. Jake has a white spot on his nose, but Lucy does not. What can you conclude from this information? - The genes for the white spot and for polydactyly are not linked. - A sex-linked gene that controls the expression of the white spot is found on the Y chromosome. - The genes for the white spot and for polydactyly are linked. - A sex-linked gene that controls the expression of the white spot is found on the X chromosome.
A sex-linked gene that controls the expression of the white spot is found on the X chromosome
Which statement is true about the determination of sex in humans? - An individual with an X and a Y will always be male. - An individual may have some genes producing proteins for maleness and other genes producing proteins for femaleness. - Any individual without a Y chromosome will always become a female. - The SRY gene alone can determine maleness.
An individual may have some genes producing proteins for maleness and other producing proteins for femaleness
Which statement regarding genotypes and phenotypes is false? - An organism with two different alleles for a single trait is said to be homozygous for that trait. - The genetic makeup of an organism constitutes its genotype. - Alleles are alternate forms of a gene. - The expressed physical traits of an organism are called its phenotype.
An organism with two different alleles for a single trait is said to be homozygous for that trait
Research since Mendel's time has established that the law of segregation of genes during gamete formation - applies to all sexually reproducing organisms. - applies to all forms of life. - applies to all asexually reproducing organisms
Applies to all sexually reproducing organisms
What type of inheritance fits the data in this pedigree? - autosomal dominant - autosomal recessive - sex-linked dominant
Autosomal recessive
In some cats, black coat color (B) is dominant over brown (b) and a striped fur pattern (S) is dominant over a marbled fur pattern (s). You rescued a black striped cat from an animal shelter but could not determine its exact genotype. To do so, you mated the cat with a brown marbled cat. The mating produced 3 brown marbled, 2 brown striped, 2 black marbled, and 3 black striped. Immediately, you concluded the genotype of your rescued cat was - BBSs. - BBSS. - BbSS. - BbSs
BbSs
You are trying to determine if a newborn boy has an X-linked genetic disorder by analyzing a family pedigree. Which of these findings would rule out the X-linked hypothesis? - Both brothers and sisters have the disorder though neither parent does.. - All the sons of the baby's grandmother have the disorder. - There are no females in the pedigree with the disorder
Both brothers and sisters have the disorder though neither parent does
The individual features of all organisms are the result of - only the environment in which the organism develops. - both the interaction between genetics and the environment. - both the environment and the needs of the individual. - only the genes present.
Both the interaction between genetics and the environment
For most sexually reproducing organisms, Mendel's laws - cannot strictly account for the patterns of inheritance of many traits. - help us understand the global geographic patterns of genetic disease. - explain the biological mechanisms behind why certain genes are dominant or recessive. - can predict whether offspring will be male or female with 100% accuracy.
Cannot strictly account for the patters of inheritance of many traits
Which statement regarding prenatal testing is false? - Ultrasound imaging has no known risk. - Chorionic villus sampling and amniocentesis are usually reserved for pregnancies with higher than usual risks of complications. - Results from chorionic villus sampling come faster than those from amniocentesis. - Chorionic villus sampling is typically performed later in the pregnancy than amniocentesis.
Chronic villus sampling is typically performed later in the pregnancy than amniocentesis
The presence of AB blood type illustrates the principle of - codominance. - pleiotropy. - polygenic inheritance. - incomplete dominance
Codominance
The mechanism that "breaks" the linkage between linked genes is - codominance. - independent assortment. - crossing over. - pleiotropy.
Crossing over
Dr. Smith's parents have normal hearing. However, Dr. Smith has an inherited form of deafness. Deafness is a recessive trait that is associated with the abnormal allele d. The normal allele at this locus, associated with normal hearing, is D. Dr. Smith's parents could have which of the following genotypes? - Dd and DD - DD and dd - Dd and Dd - dd and dd
Dd and Dd
Linked genes generally - show incomplete dominance. - reflect a pattern of codominance. - do not follow the laws of independent assortment. - show pleiotropy
Do not follow the laws of independent assortment
According to this figure, heterozygotes for this form of hypercholesterolemia suffer from the disease because they - don't produce any LDL receptors. - don't produce enough LDL receptors. - produce an abnormally shaped LDL receptor. - produce too many LDL receptors.
Don't produce enough LDL receptors
After reading the paragraph below, answer the questions that follow. A man and his wife are having trouble having a baby. Using modern technologies, the woman's eggs are removed, fertilized with her husband's sperm, and implanted into her uterus. The procedure is successful, and the woman gives birth to a healthy baby boy. After a while, though, they discover that their son is colorblind and has blood type O. The woman claims that the child can't be theirs since she has blood type A and her husband has type B. Also, neither parent is colorblind, although one grandparent (the woman's father) is also colorblind. As a genetic counselor, you would explain to the parents that - it is possible for the baby to have type O blood, since type O is inherited through a dominant allele. - the eggs must have been accidentally switched, since the baby's blood type has to match one of his parents. - each parent could have contributed one recessive allele, resulting in type O blood.
Each parent could have contributes one recessive allele, resulting in type O blood
Which statement is true of the determination of height in humans? - Height is an example of pleiotropic inheritance. - Height is determined by 9 separate genes, all of which are codominant. - Height is determined by variations in more than a hundred genes as well as environmental conditions. - Height is a situation where a single phenotypic character is determined by the additive effects of three genes.
Height is determined by variations in more than a hundred genes as well as environmental conditions
A carrier of a genetic disorder who does not show symptoms is most likely to be ________ to transmit it to offspring. - heterozygous for the trait and able - homozygous for the trait and unable - homozygous for the trait and able - heterozygous for the trait and unable
Heterozygous for the trait and able
Which trait is an example of incomplete dominance in humans? - albinism - skin color - ABO blood groups - hypercholesterolemia
Hypercholesterolemia
Which statement about sex determination in the animal kingdom is true? - In some animals, sex chromosomes determine sex and, in some animals, environmental factors such as temperature determine sex. - In all animals, sex is determined by environmental factors such as nutritional status. - Sex in all animals is determined by the presence of one or two sex chromosomes.
In some animals, sex chromosomes determine sex, and in some animals, environmental factors such as temperature determine sex
Imagine that beak color in a finch species is controlled by a single gene. You mate a finch homozygous for orange (pigmented) beak with a finch homozygous for ivory (unpigmented) beak and get numerous offspring, all of which have a pale, ivory-orange beak. This pattern of color expression is most likely to be an example of - pleiotropy. - polygenic inheritance. - codominance. - incomplete dominance.
Incomplete dominance
All the offspring of a cross between a red-flowered plant and a white-flowered plant have pink flowers. This means that the allele for red flowers is ________ to the allele for white flowers. - codominant - recessive - dominant - incompletely dominant
Incompletely dominant
Any gene located on a sex chromosome - will exhibit pleiotropy. - will exhibit codominance. - is called a recessive gene. - is called a sex-linked gene.
Is called a sex linked gene
Amniocentesis and chorionic villus sampling allow for ________ and ________ of the fetus so that it can be tested for abnormalities. - direct observation; biochemical testing - karyotyping; biochemical testing - sexing; imaging - imaging; karyotyping
Karyotyping; biochemical testing
Sex-linked conditions are more common in men than in women because - most genes associated with the sex-linked conditions are linked to the Y chromosome, which determines maleness. - the sex chromosomes are more active in men than in women. - men need to inherit only one copy of the recessive allele for the condition to be fully expressed. - men acquire two copies of the defective gene during fertilization.
Men need to inherit only one copy of the recessive allele for the condition to be fully expressed
Which statement best explains why dominant alleles that cause lethal disorders are less common than recessive alleles that cause lethal disorders? - Lethal disorders caused by dominant alleles are usually more severe than lethal disorders caused by recessive alleles. - The presence of a lethal dominant allele causes sterility. - Unlike lethal disorders caused by recessive alleles, lethal disorders caused by dominant alleles usually cause the death of the embryo. - Most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce.
Most individuals carrying a lethal dominant allele have the disorder and die before they reproduce, whereas individuals carrying a lethal recessive allele are more likely to be healthy and reproduce.\
In giraffes, long necks (N), long legs (L), dark spots (D), and the ability to digest maize (M) are all dominant traits. What possible genotype could a long-necked, short-legged, light-spotted, maize-digesting giraffe have? - NnllddMM - NNLLDdMm - nnLLddMM - NNllddmm
NnllddMM
Most people afflicted with recessive disorders are born to parents who were - slightly affected by the disease, showing some but not all of the symptoms. - both affected by the disease. - not affected at all by the disease
Not affected at all by the disease
How many sex chromosomes are normally in a human gamete? - one - two - three - four
One
What is the usual complement of sex chromosomes in a human male? - one Y chromosome and zero X chromosomes - one X chromosome and one Y chromosome - two Y chromosomes and zero X chromosomes - two X chromosomes and one Y chromosome
One X chromosome and one Y chromosome
Blood samples are taken from the heel of newborn babies to test for a mutation in the PKU gene. Why is this so important? - The government must track all cases of PKU to be sure the disease does not spread through the population. - PKU can be completely treated with dietary management of the amino acid phenylalanine, preventing any negative outcomes in the child, but the diet needs to be started immediately. - PKU is lethal in newborns if not treated immediately. - PKU inevitably leads to mental retardation, reduced skin pigmentation, and other behavior problems and the family needs to plan for care for the child.
PKU can be completely treated with dietary management of the amino acid phenylalanine, preventing any negative outcomes in teh child but the diet needs to be started immediatly
After reading the paragraphs below, answer the questions that follow. Cats normally have a total of 18 toes, 5 on each front paw and 4 on each back paw. But some cats express the dominant phenotype for polydactyly, which results in the development of extra toes on one or more paws. Jake, a Canadian tabby cat, has 28 toes and is recognized by the Guinness Book of World Records as the cat with the most toes. Suppose that Jake mates with a female cat, Lucy, who has 18 total toes. Over several years, they have multiple litters and a total of 16 kittens (10 males and 6 females). The total number of toes on each kitten ranges from 21 to 25. If we use the letter P to represent the polydactyly gene, what is Jake's genotype? - pp - PP - Pp
PP
Which statement best represents the theory of pangenesis developed by Hippocrates? - Particles called pangenes, which originate in each part of an organism's body, collect in the sperm or eggs and are passed on to the next generation. - Pregnancy is a spontaneous event, and the characteristics of the offspring are determined by the gods. - Offspring inherit the traits of either the mother or the father, but not both. - Pangenes are influenced by the environment and the behaviors of the parents.
Particles called pangenes, which originate in each part of an organism's body, to collect in the sperm or eggs and are passed on the the next generation
Mendel conducted his most memorable experiments on - guinea pigs. - fruit flies. - peas. - roses.
Peas
Blood samples are taken from the heel of newborn babies to test for a mutation in the PKU gene, which, if left untreated and in severe cases, can lead to mental retardation, reduced skin pigmentation, an- seizures. Which concept is being illustrated by this example? - pleiotropy - incomplete dominance - polygenic inheritance - codominance
Pleiotrophy
Sickle-cell disease is an example of - a trait with more than two alleles. - pleiotropy. - polygenic inheritance.
Pleiotrophy
Which term refers to a situation where a single phenotypic character is determined by the additive effects of two or more genes? - codominance - incomplete dominance - polygenic inheritance - pleiotropy
Polygenic inheritance
Which plants in this figure must all be heterozygous? - purple-flowered plants in the F1 generation - purple-flowered plants in the P generation - white-flowered plants in the P generation - purple-flowered plants in the F2 generation
Purple-flowered plants in the F1 generation
Most genetic disorders of humans are caused by - multiple alleles. - a mutation that occurs in the egg, sperm, or zygote. - dominant alleles. - recessive alleles.
Recessive alleles
After reading the paragraphs below, answer the questions that follow. During a summer study abroad program, you traveled to Austria to study genetics at the University of Vienna. While you were there, a momentous discovery was made: Some of Gregor Mendel's original lab books and notes were found to be buried outside of the abbey where he lived. It just so happened that the professor you were working with obtained copies of these notes and enlisted your help to decipher them. You hired a translator to translate Mendel's notes from Czech to English, and using your knowledge of modern genetics (which Mendel did not have!) you were able to construct a partial Punnett square for crosses with peas (shown here). Because the notebook was damaged from being buried for so long, this is the only information that you have regarding a cross that Mendel must have performed. Your professor has tasked you with figuring out more about this experiment. In pea plants, round peas are dominant (R) and shriveled peas are recessive (r), and yellow peas (shown as light gray in the Punnett square) are dominant (Y) and green peas (dark gray) are recessive (y). Using this information and the partial Punnett square shown, what phenotype should be in the square labeled B? - round and yellow - shriveled and yellow - round and green - shriveled and green
Round and green
After reading the paragraphs below, answer the questions that follow. During a summer study abroad program, you traveled to Austria to study genetics at the University of Vienna. While you were there, a momentous discovery was made: Some of Gregor Mendel's original lab books and notes were found to be buried outside of the abbey where he lived. It just so happened that the professor you were working with obtained copies of these notes and enlisted your help to decipher them. You hired a translator to translate Mendel's notes from Czech to English, and using your knowledge of modern genetics (which Mendel did not have!) you were able to construct a partial Punnett square for crosses with peas (shown here). Because the notebook was damaged from being buried for so long, this is the only information that you have regarding a cross that Mendel must have performed. Your professor has tasked you with figuring out more about this experiment. In pea plants, round peas are dominant (R) and shriveled peas are recessive (r), and yellow peas (shown as light gray in the Punnett square) are dominant (Y) and green peas (dark gray) are recessive (y). Using this information and the partial Punnett square shown, what genotype should be listed in the square labeled A? - RrYy - rrYy - RRyy - RRYY
RrYy
After reading the paragraphs below, answer the questions that follow. During a summer study abroad program, you traveled to Austria to study genetics at the University of Vienna. While you were there, a momentous discovery was made: Some of Gregor Mendel's original lab books and notes were found to be buried outside of the abbey where he lived. It just so happened that the professor you were working with obtained copies of these notes and enlisted your help to decipher them. You hired a translator to translate Mendel's notes from Czech to English, and using your knowledge of modern genetics (which Mendel did not have!) you were able to construct a partial Punnett square for crosses with peas (shown here). Because the notebook was damaged from being buried for so long, this is the only information that you have regarding a cross that Mendel must have performed. Your professor has tasked you with figuring out more about this experiment. In pea plants, round peas are dominant (R) and shriveled peas are recessive (r), and yellow peas (shown as light gray in the Punnett square) are dominant (Y) and green peas (dark gray) are recessive (y). Using this information and the partial Punnett square shown, what were the phenotypes of the parental plants that were used in this cross by Mendel? - RRyy and rryy - Rryy and rrYy - RrYy and RrYy - Rryy and RrYy
Rryy and RrYy
Which statement regarding sickle-cell disease is false? - Persons who are heterozygous for sickle-cell disease are also resistant to malaria. - About 1 in 10 African Americans is a carrier of sickle-cell disease. - The multiple symptoms of sickle-cell disease result from the actions of just one allele. - Sickle-cell disease causes white blood cells to be sickle-shaped.
Sickle-cell disease causes white blood cells to be sickle-shaped
After reading the paragraph below, answer the questions that follow. A man and his wife are having trouble having a baby. Using modern technologies, the woman's eggs are removed, fertilized with her husband's sperm, and implanted into her uterus. The procedure is successful, and the woman gives birth to a healthy baby boy. After a while, though, they discover that their son is colorblind and has blood type O. The woman claims that the child can't be theirs since she has blood type A and her husband has type B. Also, neither parent is colorblind, although one grandparent (the woman's father) is also colorblind. In regard to the baby's color blindness, a sex-linked recessive trait, you explain that - the baby's father must have a recessive allele for color blindness. - the eggs must have been accidentally switched, since males inherit sex-linked traits only from their fathers. - since color blindness is sex-linked, a son can inherit color blindness if his mother has the recessive color blindness allele. - color blindness often appears randomly, even if neither parent is colorblind.
Since color blindness is sex-linked, a son can inherit color blindness if his mother has the recessive colorblindness allele
Maternal inheritance patterns from generation to generation cannot be analyzed by simply studying the X chromosome in the way that paternal inheritance patterns can follow the Y chromosome because - the X chromosome is obtained from both the father and the mother. - the X chromosome is too large to analyze effectively. - the X chromosome sometimes exchanges genetic information with the Y chromosome. - one X chromosome is deactivated in females.
The X chromosome is obtained from both the father and the mother
Mendel's law of independent assortment states that - independent sorting of genes produces polyploid plants under some circumstances. - genes are sorted concurrently during gamete formation. - chromosomes sort independently of each other during mitosis and meiosis. - the allele that a gamete receives for one gene does not influence the allele the gamete receives for another gene.
The allele that a gamete receives for one gene does not influence the allele the gamete receives for another gene
Imagine that we mate two black Labrador dogs with normal vision and find that three of the puppies are like the parents, but one puppy is chocolate with normal vision and another is black with PRA (progressive retinal atrophy, a serious disease of vision). We can conclude that - the same alleles that control coat color can also cause PRA. - both of the parents are homozygous for both traits. - the alleles for color and vision segregate independently during gamete formation.
The alleles for color and vision segregate independently during gamete formation
The chromosome theory of inheritance states that - the behavior of chromosomes during mitosis accounts for inheritance patterns. - humans have 46 chromosomes. - chromosomes that exhibit mutations are the source of genetic variation. - the behavior of chromosomes during meiosis and fertilization accounts for patterns of inheritance.
The behavior of chromosomes during meiosis and fertilization accounts for patters of inheritance
What is the most likely explanation for the occurrence of an X-linked genetic disorder in the boy at the bottom of the pedigree shown? - The boy inherited the kind of allele that skips every other generation. - The boy has a new mutation for the disorder. - The boy inherited this allele from his father only. - The boy inherited this allele from his mother only.
The boy has a new mutation for the disorder
Which of the following kinds of data could be used to map the relative position of three genes on a chromosome? - the frequencies with which the genes are inherited from the mother and from the father - the frequencies with which the corresponding traits occur together in offspring - the frequencies with which the genes exhibit incomplete dominance over each other - the frequencies of mutations in the genes
The frequencies with which the corresponding traits occur together in offspring
A colorblind woman marries a man who is not colorblind. All of their sons, but none of their daughters, are colorblind. Which of the following statements correctly explains these results? - The gene for color vision is incompletely dominant to the gene for sex determination. - The gene for color vision is found on the Y chromosome. - The gene for color vision is codominant with the gene for sex determination. - The gene for color vision is found on the X chromosome.
The gene for color vision is found on the X chromosome
Which statement regarding cross-breeding and hybridization is false? - The parental plants of a cross are the P generation. - The offspring of two different varieties are called hybrids. - The hybrid offspring of a cross are the P1 generation. - The hybrid offspring of an F1 cross are the F2 generation.
The hybrid offspring of a cross are the P1 generation
DNA kits do not provide information on - the amount of Neanderthal DNA present. - the likely sex ratio of one's offspring. - the presence of alleles for certain diseases such as cystic fibrosis. - the possible region of one's ancestry.
The likely sex ratio of ones offspring
Recessive X-linked traits are more likely to be expressed in a male than a female because - the male chromosome is more susceptible to mutations. - the male chromosome is more fragile than the female chromosome. - the male's phenotype results entirely from his single X-linked gene.
The males phenotype results entirely from his single X-linked gene
You prepare a human karyotype. Upon analysis, you find 22 pairs of chromosomes that are each of approximately equal length and also a single pair that has one chromosome longer than the other. What can you conclude from this information? - The organism that this cell came from is likely a male. - This cell is likely haploid. - The organism that this cell came from is likely a female. - The organism that this cell came from has a genetic disease.
The organism that this cell came from is likely a male
The alleles of a gene are found at ________ chromosomes. - the same locus on homologous - the same locus on nonhomologous - different loci on homologous - different loci on nonhomologous
The same locus on homologous
Varieties of plants in which self-fertilization produces offspring that are identical to the parents are referred to as - true-breeding. - monohybrid crosses. hybrids. - the F2 generation
True-breeding
You are trying to determine the linkage map of a series of genes, X, Y, and Z, from Caenorhabditis elegans, a nematode worm commonly used in scientific research. From doing several crossover experiments, you know that the recombination frequency between X and Y is 11.5%, between Y and Z is 13%, and between X and Z is 25%. What is a possible sequence of these genes? - Z-X-Y - Y-Z-X - X-Y-Z - X-Z-Y
X-Y-Z
The usual sex chromosome complement of a human female is - XO. - XY. - YY. - XX.
XX