Biology Ch. 10
Wavy hair is incompletely dominant to straight or curly hair. What is the expected outcome if two individuals with wavy hair were to have children?
1 curly: 2 wavy: 1 straight
Use a Punnett square to determine the phenotypic ratio of offspring from parents with blood types AB and O.
1:1
If a population has two alleles for an X-linked gene, how many different MALE genotypes are possible?
2
Mendel researched pea plants that contained how many varieties of traits even though he only selected for 7 of them.
22
You mate a plant that is true-breeding for green pea pods (dominant) with one that is true-breeding for yellow pea pods (recessive) and obtain offspring that are heterozygous for pea pod color. You then allow these offspring to self fertilize and obtain 100 offspring. How many do you expect to have the recessive phenotype?
25
If a population has two alleles (one is dominant and the other is recessive) for an X-linked gene, how many different FEMALE genotypes are possible?
3
Shows the dominant trait if it is homozygous dominant and the recessive trait if it is homozygous recessive.
A homozygous individual
The relationship between person A and person B on the pedigree is best described how? (diagram)
A is grandfather to granddaughter B.
Which individuals would express a dominant phenotype?
AA Aa because the capitalize letter is first, but it is the same letter
What human blood type is an example of a co-dominance trait?
AB
In horses, a coat color called roan occurs when two different coat colors are fully expressed. For example, some hairs would be black and some would be white in the offspring between a white male and a black female. This is called
Co dominance
What would be an example of a testcross?
Crossing a homozygous recessive with an individual showing the dominant trait but with an unknown genotype
The first generation of offspring of the original parents (P generation) are referred to as the what?
F1
What items are placed at the tops of the columns and the fronts of the rows in a Punnett square?
Gametes
What is included in Mendel's law of segregation?
Gametes contain only one of the two parental alleles. Individuals have two alleles for each trait Fertilization restores two alleles of each gene to the embryo. Pairs of alleles separate during gamete formation
What are the possible ABO blood group genotype(s) of offspring of parents with genotypes IA IB and IB i?
IA i IB IB IB i IA IB
How did Mendel's model of heredity contribute to the theory of evolution?
It accounted for variation amongst closely related individuals.
In a monohybrid cross, the expected phenotypic ratio is 3:1. This means that
One would expect to see 3/4 of the offspring to show the dominant trait and 1/4 to show the recessive trait.
Marfan syndrome has been linked to a single gene. Symptoms of this syndrome include long arms, legs, hands and feet, a weakened aorta, and poor eyesight. These multiple symptoms linked to a single gene are an example of which of the following?
Pleiotropy
This is evident when one gene shows multiple effects and is usually associated with a genetic mutation.
Pleiotropy
gene can be found on the Y chromosome but it does not have a complimentary version on the X chromosome
SRY
Which choice describes incomplete dominance?
The heterozygous individual shows a phenotype in-between that of an individual homozygotic for either allele.
Which of the following statements is/are true about people who are carriers for an autosomal recessive disorder?
They can pass the recessive allele to their offspring. They can have a child with the disorder. They are heterozygous. They can pass the dominant allele to their offspring.
Identify the heterozygous genotype.
Tt Because they are different (hetero)
More males than females have recessive sex-linked disorders because recessive alleles on the __ chromosome are always expressed in males
X
The X and Y chromosomes differ immensely in their gene content. As such, sex-linked traits are (almost) always on the ______ chromosome.
X
This pedigree represents a(n) _________ pattern of inheritance. (diagram)
X linked recessive
Which of the following represent normal combinations of sex chromosomes in humans?
XX XY
Which of the following genotypes represent color blind individuals?
XbXb XbY
All of the sons but none of the daughters of a couple have a genetic condition. The father also has the same condition but the mother does not. This is an example of a(n)
Y linked condition
A male is colorblind if he inherits
a recessive allele from his mother.
Which of the following is an example of an individual with a recessive trait?
aa NOT AA, Aa, or Ab
In cases of polygenic inheritance, the effects of dominant alleles are
additive, so that individuals with more dominant alleles show the extreme of the trait.
In a type of flowering plant, a true-breeding white flowered plant is crossed with a true-breeding red flowered plant. If flower color is a type of incomplete dominance, what flower color will the offspring have?
all pink
Which of the following characterizes traits controlled by more than one set of alleles?
alleles have additive affects on phenotype phenotypic variation appears continuous
In a genetic cross, filial generation (F) refers to
any generation following the parental generation.
disorders are caused by mutated alleles on non-sex chromosomes.
autosomal
traits carried on non-sex chromosomes
autosomal
This pedigree shows the pattern of inheritance of what? (diagram)
autosomal DOMINANT disorder
If a child has an autosomal disorder but both parents are normal, this is described as a(n) autosomal what?
autosomal RECESSIVE disorder
The pattern of inheritance occurring when two heterozygous parents who have a genetic disorder produce a child who does not have that genetic disorder is ______.
autosomal dominant disorder
This pedigree shows the pattern of inheritance of what? (diagram)
autosomal dominant disorder.
This pedigree shows the pattern of inheritance of a(n) _____ disorder. (diagram)
autosomal recessive
Autosomal traits are carried on _____ while sex-linked traits are carried on _____.
autosomes sex chromosomes
What describes the geneticist, Gregor Mendel.
careful, deliberate note-taker followed the scientific method closely integrated mathematics into his studies
If two heterozygous parents, who do not have a particular genetic condition, produce a child who has the condition, the parents are referred to as what?
carriers
Individuals who are heterozygous for a trait are said to
carry the recessive trait
X-linked traits are found on the X chromosome and
code for a variety of traits
If a father has a dominant X-linked genetic disorder and the mother does not, their ______ will have a 100% chance of having the disorder.
daughters
A genetic condition for which a daughter has a 100% chance of inheritance if her father has the condition is called X-linked _____.
dominant
An allele that masks the expression of an alternate form of that same gene is called what?
dominant
When both parents are heterozygous and express a condition but their child is unaffected, the disorder must be autosomal
dominant
Mendel's models are compatible with evolution because they show that various traits are tested by the ____________________________ and those that are the most successful will be passed on.
environment
In Siamese cats, temperature affects a(n) ______, which in turn influences hair color.
enzyme
True or false: Traits and disorders are only inherited via alleles from sex chromosomes (X and Y).
false
True or false: Y-linked disorders are present only in males and are passed directly from the father to 50% of his sons and 50% of his daughters.
false
Human eye color is a trait that is best described as being the result of what?
gene interaction.
The particular set of alleles an individual receives at fertilization is called its __________.
genotype
In a genetic cross, the F2 individuals are the ______ of the P generation.
grand offspring
Carriers of a trait are what?
heterozygous for that trait.
An organism carrying both dominant alleles of a particular gene would be considered __________ dominant for that trait.
homozygous
A recessive allele is expressed only in the
homozygous recessive.
In Himalayan rabbits, where does dark hair color arise?
in parts of the body with high heat loss
A mother with straight hair and a father with curly hair have a child with wavy hair. This is an example of what type of dominance?
incomplete
A heterozygote displaying a third variation of a trait—a phenotype in between that of individuals homozygotic for both alleles— is an example of
incomplete dominance
Human eye color is an example of a phenotype that results from the ________ multiple gene products (enzymes and proteins).
interaction of
The genotype of an organism is
its genetic makeup.
Genes that are found on the X chromosome, but not on the Y chromosome or on autosomes, are X-___________________ genes
linked
On the diagram of the pedigree, a square with the circle around it is best described as a
male with a genetic disorder.
A chart of a family's history with regard to a particular trait, in which males are designated by squares and females by circles, is a ____.
pedigree
A condition in which a single mutant gene affects more than one distinct characteristic of an individual is referred to as _______ and often leads to a syndrome.
pleiotropy
A condition in which two or more sets of alleles control genetic patterns is the result of _____ inheritance.
polygenic
A diagram used for estimating genetic probability is called a
punnett square
If a child has an autosomal disorder but both parents are normal, this is described as a(n) autosomal ____________________________ disorder
recessive
What is an example of a phenotype?
red feathers
traits carried on the sex chromosomes
sex linked
Traits found on the non-autosomal chromosomes are called
sex-linked.
In humans, the sex chromosome carried by the ______ determines the sex of the resulting offspring.
sperm
In a pedigree, squares represent _______________________ and circles represent ________________________________
squares - males circles - females
Which advanced form of data analysis did Mendel use in his experiments?
statistics
Pleiotropy often results in a group of symptoms that appear together, usually referred to as a .
syndrome
Mendel bred an unknown plant displaying a dominant phenotype with an individual showing the recessive phenotype; then, he analyzed the offspring to determine the unknown genotype. This experiment is called a(n)
testcross
What are reasons that garden peas ended up being a good organism for genetic experiments?
true breeding lines could be established, easy to cultivate, could be manually cross-pollinated, phenotypic traits were simple and distinct, and had many easily identifiable traits
According to Mendel's law of segregation, each individual has___________________ factor(s) for each trait, which segregate during the formation of gametes such that each gamete contains _____________________ factor(s) from each pair of factors.
two one