bio ch 12 connect
Which of the following plants was the main organism for Mendel's genetic experiments?
Pea
A trait that has multiple genes contributing to its expression is known as which of the following?
Polygenic trait
Which of these is commonly used to predict the results of simple genetic crosses?
Punnett square
In terms of probabilities, the cross of a tall yellow seeded pea plant (TTYy) with a tall green seeded pea plant (Ttyy) is equivalent to which two monohybrid crosses?
TT x Tt and Yy x yy
The inheritance patterns of many traits are (more or less) complex than simple Mendelian patterns.
More
Juvenile glaucoma is a hereditary disease that causes blindness due to the degeneration of nerves in which of the following?
Optic nerve
homozygous dominant; heterozygous; homozygous recessive
TT; Tt; tt
Which of the following are examples of environmental effects on phenotype?
The amount of sunlight experienced by a sunflower affects the number of seeds produced. The number of seeds eaten by a bird affects its weight.
A cross in which only a single trait is considered is called a(n) ______ cross or single factor cross
monohybrid
An experimental cross where only a single characteristic is considered (for example, flower color) is called
monohybrid
In order to determine the likelihood of having a flipped coin come up on heads three times in a row, you would use the
multiplication rule
Choose the two dominant alleles in the human ABO blood group system.
IB IA
Which of the following statements about the number of alleles a gene can have is true?
In a population of organisms, a gene can be represented by more than two alleles.
If the offspring from a testcross contain only heterozygotes, the genotype of the unknown parent must be
homozygous dominant
The results of a testcross indicate that all of the offspring have a dominant phenotype. The genotype of the parent in question must be
homozygous dominant
The physical appearance or other observable characteristic of an individual is called his/her
phenotype
Which of these traits exhibit a dominant mode of inheritance?
Polydactyly; Mid-digital hair; Hypercholesterolemia
A(n) ___ square can be used to predict the outcome of a simple genetic cross.
Punnett
A parent with a genotype of RrYy can produce which of the following gametes?
RY; rY; Ry; ry
Which of these blood phenotypes is NOT properly matched with the sugar exhibited on red blood cells?
Type O - have galactosamine and galactose
When the interaction of genes alters genetic ratios, this is called
epistasis
sickle cell anemia
defective hemoglobin
Polydactyly
extra fingers or toes
An individual's total set of alleles for a particular trait is called his/her _____
genotype
Type A
have galactosamine
Type AB
have galactosamine and galactose
Type B
have galactose
An allele that has more than one effect on phenotype is called
pleiotropic.
In Mendel's experiments, he observed a 3:1 ratio between dominant and recessive traits in
the F2 generation of monohybrid crosses.
Place the three stages of Mendel's experiments in the correct order from first (on top) to last.
1) Allowing plants to self cross to ensure they are true breeding 2) Reciprocal; crosses between true breeding varieties 3) Allowing hybrid offspring to self fertilize
One of the parents in a dihybrid cross has the genotype AABb. How many types of gametes can this parent produce?
2
A Punnett square for a single trait should be set up as a ______ square (Not counting the squares for parental gametes).
2 x 2
What was the ratio that Mendel observed between dominant and recessive traits in the F2 offspring of a monohybrid cross?
3 dominant:1 recessive
In a homozygous recessive individual the probability of the dominant allele being present is
0
In a heterozygous individual, the probability of a recessive allele being present in a gamete is
0.5
When continuous traits are graphed in the form of a histogram with the phenotype on the X-axis, and the frequency of individuals with that phenotype on the Y-axis, a ____ -shaped curve results.
Bell
Huntington's disease
Degeneration of the nervous system
What type of cross follows the simultaneous inheritance of two different traits?
Dihybrid cross
True or false: Mendel's observations did not support the independent assortment hypothesis.
False
Which of the following traits is NOT described correctly?
Huntington disease: wasting away of muscles during childhood
Of the following alleles for blood type, indicate which two alleles are codominant to each other.
IA IB
The probability of genotypes in an independently assorted dihybrid cross is based on the probabilities of
two monohybrid crosses
Multiplication rule
used for independent events
addition rule
used for mutually exclusive events
In the cross of Pp x Pp four outcomes are possible: PP, Pp, pP, and pp. The probability of being heterozygous is ________.
1/2
A 9:3:3:1 ratio is obtained in the F2 generation of a dihybrid cross when alleles assort ___ from one another.
Independently
Which of the following conditions is inherited due to a dominant allele?
Juvenile glaucoma
Albinism;
Lack of melanin pigmentation
The following pedigree is representative of which type of inheritance? 1st generation: Unaffected male and female, 1 of them is heterozygous. 2nd generation: 3 children (unaffected male, female carrier married to male carrier, and male carrier married to unaffected female). 3rd generation: 2 different families ( female and male carrier from 2nd generation have 4 children: affected male, unaffected female, affected female, female carrier). Other family of male carrier and unaffected female from 2nd generation: male carrier, unaffected male and female). 4th generation: the female and male carriers (1st cousins of 3rd generation) have 3 children: unaffected male and female, homozygous recessive male
Recessive
Which of these traits is NOT correctly matched with its mode of inheritance?
Red-green color blindness: dominant
Hemophilia;
inability of blood to clot properly
The appropriate time to use the product rule is when dealing with events that are:
independent
A 9:3:3:1 ratio is obtained in the F2 generation of a dihybrid cross when alleles assort _____ from one another.
independently
Human height is an example of a trait that has a continuous distribution of phenotypes. Human height is therefore an example of _____ inheritance.
polygenic
Quantitative traits are usually
polygenic
Traits that exhibit continuous variation are also called
quantitative traits
When performing a monohybrid cross, Mendel noticed that not all individuals in the F2 generation were true breeding. What proportion were not?
1/2 of the F2 individuals exhibiting the dominant form were not true breeding.
In a certain plant, fruit color is affected by an epistatic interaction between two genes. The fruit is red in the presence of at least one dominant allele of either or both gene A or gene B, and white when there are no dominant alleles present. What proportion of the offspring of a cross of AaBb x AaBb plants is expected to be red?
15/16
A 3:1 phenotypic ratio in the F2 generation of a monohybrid cross represents this genotypic ratio:
1:2:1
This ratio is obtained in the F2 generation of a dihybrid cross when alleles assort independently from one another.
9:3:3:1
In pea plants, the allele T encodes for tall plants, while the allele t encodes for dwarf plants. If a true-breeding tall pea plant is crossed with a true-breeding dwarf pea plant what are the expected genotypes of the offspring?
All Tt
The trait for round (R) peas is dominant over the trait wrinkled (r) peas. What would happen if true-breeding round peas are crossed with true-breeding wrinkled peas?
All offspring will have round peas.
Choose statements that correctly refer to components of Mendel's five-element model (please note that the answers use the modern term gene instead of factor).
Alternative forms of genes are called alleles; Parents transmit genes to offspring; The two alleles remain discrete; The presence of an allele doesn't ensure that it will be expressed.
Which of the following is NOT one of the three main stages that Mendel conducted his experiments in?
Back crosses between F1 and P individuals
Which pattern of inheritance MOST likely explains the inheritance of the trait shown in this pedigree? 1st generation: Affected male and unaffected female (3 children: unaffected male, affected male married to unaffected female and affected female married to unaffected male) 3rd generation: Affected male and unaffected female of 2nd generation have an affected female. The affected female and unaffected male of 2nd generation have 2 affected females.
Dominant
Choose the 4 reasons that contributed to Mendel selecting the garden pea as his experimental subject.
Earlier investigators had produced hybrid peas.; The garden pea had a relatively short generation time.; There were a large number of pure varieties.; Garden peas can self-fertilize.
In a typical monohybrid cross, all of the offspring in which generation will exhibit a single trait without blending?
F1
True or false: Due to the diploid nature of eukaryotic cells, a gene can never have more than two alleles in a population of organisms.
False
What type of experiment involves mating two individuals with different characteristics to each other? One individual provides females gametes, while the other provides male gametes.
Hybridization
Which of these are not reasons that Mendel chose to study the garden pea:
They were inexpensive to buy; Long generation time
In order to predict the outcome of mutually exclusive events, this rule should be used:
addition
Mendel's observations supported the independent _____ hypothesis
assortment
Prior to the work of Mendel, inheritance was viewed as resulting from
blending of traits from an offspring's parents.
A(n)____ cross follows the simultaneous inheritance of two different characters.
dihybrid
Type O
have neither sugar
Prior to the 20th century, the two main ideas that provided the basis for most thinking about heredity were
heredity occurs within species; traits are transmitted directly from parents to offspring
Consider a testcross where the unknown parent is heterozygous. The offspring will be
heterozygotes and homozygotes
Pedigree analysis is typically used for studying:
human traits that follow simple inheritance patterns
In the monohybrid crosses performed by Mendel, the F1 plants always displayed
one trait
This analysis is appropriate for studying traits, such as genetic diseases, that follow simple Mendelian patterns:
pedigree
Sickle cell anemia is caused by a _____ allele because this mutation has more than one effect on the phenotype.
pleiotropic
Match each example with the type of fertilization it represents: reciprocal fertilization matches; cross-fertilization; self-fertilization matches
pollen from a white-flowered plant is used to fertilize a purple-flowered plant, while pollen from a purple-flowered plant is used to fertilize a white-flowered plant; pollen collected from a white flower introduced into a purple flower with male parts removed; Choice, takes place within an individual flower if it is not disturbed takes place within an individual flower if it is not disturbed
Continuous phenotypic variation results from
polygenic inheritance and independent segregation of genes
To calculate the probability that if a woman has four children, they will all be girls, you should use the
product rule
An example of a ____ cross is using pollen from a green-seeded pea plant to fertilize a yellow-seeded pea plant and then using pollen from a yellow-seeded pea plant to fertilize a green-seeded pea plant.
reciprocal
In order for Mendel's simple ratios to hold true, the following assumption must be made:
that the traits are inherited independently
Examples of environmental influences on phenotype include
the pattern of coat color in Siamese cats the pattern of coat color in Himalayan rabbits
Which of the following is NOT a component of Mendel's five-element model (please note that the answers use the modern term gene instead of factor)?
the two alleles are usually the same
One of the traits that Mendel studied in pea plant is plant height. Tall plants are dominant with respect to dwarf plants. If the gene for this trait is denoted by the letter "T", then the genotype of a dwarf pea plant is
tt
A hybridization experiment involves mating
two individuals with different characteristics to each other
A Punnett square has rows and columns which represent gametes made by males and females. At the intersection of each row and column we combine the corresponding gametes to produce the genotype of a potential
zygote
