Mendel's Principles of Heredity
What is the probability that an offspring from a cross of two Bb individuals will also have the genotype Bb?
1/2
A tall pea plant with axial flows has the genotype Tt Aa. What are the gamete possibilities of this plant?
1/4 for all gamete combinations
The probability of producing a dwarf plant from two heterozygous parents is 1/4. What is the likelihood that these same parent plants will produce 3 out of 3 dwarf plants?
1/64 or 1.6%
What is the probability that a couple will have three consecutive offspring that are all male?
1/8 or 12.5%
Because of independent assortment an individual with a genotype of RR YY will produce which of the following types of gametes?
100 % R Y
Tall (T) is dominant to dwarf (t). An F1 hybrid plant from a cross between a pure breeding tall and a pure breeding dwarf plant is allowed to self fertilize. What percentage of each genotype is expected in the F2 generation?
25% TT, 50% Tt, 25% tt
When flipping a coin, what is the probability of the coin landing with the head side up?
50%
What is the expected phenotypic ratio among the progeny when a plant that is heterozygous for alleles controlling two traits is allowed to self fertilize?
9:3:3:1
Determine the possible gametes that could be formed from an organism with the genotype AA Bb Cc
A B c A b c A B C A b C
Which of the following are examples of a pure-breeding line? Assume that the tall trait is dominant to the short trait. Check all that apply.
A population of short plants whose parents were all short and a population of tall plants with purple flowers that have produced the same phenotype for several generations
Two plants have different form of a gene that determine pea pod color. One plant has yellow pods, and the other green. What are the different forms of the pea pod color gene called?
Alleles
Select all examples of continuous traits.
Amount of milk a cow produces in liters and measurements of human blood pressure
Which of the following represent heterozygous genotypes?
Bb Cc and Cc
Hunington's disease is caused by the dominant allele HD. Why is HD dominant?
Because the presence of the normal protein does not prevent the mutant protein from damaging nerve cells.
Mendel performed reciprocal crosses by reversing the traits of the male and female plants. The results of each cross were similar, What did Mendel conclude based on these experiments?
Both sperm and egg contribute equally to inheritance.
A true breeding tall pea plant with yellow seeds is crossed with a true breeding short pea plant that has green seeds and the offspring are allowed to self-fertilize. What type of cross is this?
Dihybrid cross A dihybrid cross is a cross between parent with variant characters for two traits
Select all examples of discrete traits.
Dogs that can have long or short hair, A rabbits that can have white or black fur, or pea plant seeds that are green or yellow
Which of the following are gametes?
Eggs and Sperm
If a genetic study began with your grandparents, which generation would represent you and your siblings?
F2
True or false: Currently, it is impossible to determine if a person has Huntington disease until symptoms appear.
False
Presence of freckles (FF or Ff) is dominant to lack of freckles (ff). If a male who has freckles mates with a female that does not have freckles, what combination of alleles will be present in the F1 generation?
Ff or ff
The scientist shown in the image who was the monk performed the first seminal genetic experiments is ..................
Gregor Mendel
From the list below, choose all that are correctly written genotype used by human geneticists.
HD^+ HD, CF^+ CF^+
.................. refers to the transmission of physiological, anatomical, and behavioral traits from parents to offspring
Heredity
The alleles of two different genes will be distributed randomly into gametes. This statement summarizes which of Mendel's laws?
Law of independent assortment
List the events of pollination in the correct order (start at the top).
Male gametes are produced in pollen grains and eggs are formed in the ovules a pollen grain lands on the stigma, a pollen tube forms, and an ovule is fertilized
List the events of pollination in the correct order
Male gametes are produced in pollen grains and eggs are formed in the ovules, a pollen grain lands on the stigma, a pollen tube forms, and an ovule is fertilized
The results of an experiment can be skewed by random chance. Why were the results of Mendel's numerous crosses so consistent?
Mendel analyzed large numbers of plants
Which of the following statements about Mendel's immediate contribution to genetics are true?
Mendel's data was largely ignored for more than 30 years and because Mendel was a monk and not a university professor, his work did not receive much attention from other scientists.
An organism's genotype is Rr Yy and it produces gametes with the genotypes R Y, R y, r Y, and r y with equal frequency. Which of Mendel's laws explains this fact?
Mendel's law of independent assortment
In the genetic study that begins with you and your mate, you and your mate would be considered the .................. generation
P
What term describes the observable characteristics that result from the expression of a gene?
Phenotype
.....................refers to the likelihood that an event will occur.
Probability
In a series of dihybrid crosses, pea plants with round, green seeds were crossed to plants with wrinkled, yellowed seeds. All of the progeny had round, yellow seeds. What conclusions can be drawn from these data?
Round is dominant to wrinkled and yellow is dominant to green
Which operation of probability should be used to analyze mutually exclusive outcomes of genetic crosses?
Sum rule
The two types of gametes produced by an organism with the genotype Tt are ...........and............
T and t
Consider a dihybrid cross where the true-breeding parent are tall pea plants that produce purple flowers, and short pea plants that produce white flowers. All of the F1 offspring are tall pea plants and produce purple flowers. Which of the following F2 phenotypes (produced after F1 plants are allowed to self-fertilize) are recombinant types?
Tall plants with white flowers and short plants with purple flowers
Which of the following statements refer to phenotypes?
The P generation has both tall and dwarf plants and the F1 generation has all tall plants
Why was the common garden pea plant, Pisum sativum, that Mendel used in his genetic experiments an ideal specimen to study genetic crosses?
The Pisum sativum plants that he used were true breeding with two distinct genotypes and phenotypes
A pea plant requires an enzyme to produce flowers that are purple. If this enzyme is not functional, the flowers will be white. Based on this information, which of the statements are true?
The allele for the white flower phenotype is most likely recessive to the normal allele and the non-functional allele is most likely recessive to the normal allele.
Which of the following is an example of a hybrid?
The offspring of a pea plant with yellow seeds and a pea plant with green seeds
Select all of the reasons that the common garden pea plant, Pisum sativum, was an ideal species to study genetic crosses.
The plant has discrete traits, the plants are easy to grow and produce large numbers of offspring, and the plants can be self-fertilized
If a parent with the genotype Aa Bb mates with a parent who is aa bb, what is the probability of an Aa bb offspring?
The probability of the offspring being heterozygous for the A gene is 1/2. The probability of the offspring being homozygous recessive for the B gene is 1/2. Using the product rule, 1/2 x1/2 = 1/4
What is the purpose of performing a test-cross?
To determine the genotype of an organism expressing the dominant phenotype
Which of the following represent examples of artificial selection?
Using pollen form plants that produced the largest ears of corn and breeding only dogs that have an excellent sense of smell for several generations
An allele that specifies a normally functioning gene in a human is typically written as the name of the gene followed by...................
a superscript +
Before Mendel's experiments, many scientists thought that the features of offspring are the result of ................... inheritance. According, to this concept, parental traits are mixed and forever changed in the offspring.
blended
A cross in which the pollen and egg come from different plants is called..................
cross fertilization
In humans, the normal CF+ allele specifies a protein called...................transmembrane conductance ...................
cystic fibrosis , regulator
When the presence of a single allele for a character of a trait is sufficient for the expression of that character, it is called a ..................
dominant character
The .................. is the basic unit of inheritance.
gene
Mendel proposed that genetic determinants are inherited as discrete units that are unchanged when passed from generation to generation. These units of inheritance are now known as...................
genes
The term to describe the basic unit of heredity that influences an organism's trait is..................
genes
A Tt pea plant will be tall. The symbol Tt represents the plant's...................
genotype
The genetic composition of an individual is the ..................
genotype
If a diploid organism carried the allele for purple flowers and the allele for white flowers the organism would be considered..................
heterozygous
If an organism has two identical alleles of a particular genem it is said to be..................
homozygous
The genotype AA bb CC dd is .....................
homozygous
The symptoms of Huntington disease are not present at birth and only manifest themselves later in life. For this reason, Huntington disease is known as a .....................-..................... genetic trait
late - onset
A pea plant heterozygous for yellow seeds is crossed with another plant that is heterozygous for yellow seeds. This is an example of a .................. cross
monohybrid
An organism with one dominant and one recessive allele for a single trait is ..................
monohybrid
Consider a dihybrid cross where the true breeding parents are tall pea plants that produce purple flowers, and short pea plants that produce white flowers. All of the F1 offspring are tall pea plants and produce purple flowers. Therefore, all of the F1 progeny are...................
parental type
To determine inheritance patterns in humans, researchers use a chart called a .................. that represents a family relationships.
pedigree
The product rule can used to..................
predict the probability of two or more independent events
One limitation of selective breeding prior to Mendel's work was the inability to...................
predict when offspring would inherit a valuable trait
Mendel used pollen from a purple flowered pea plant to fertilize a white flowered pea plant. He also used pollen from a white-flowered pea plant to fertilize a purple-flowered pea plant. This approach is called making ................... crosses
reciprocal
..................-fertilization is a cross in which the pollen and egg come from the same plant
self
What type of cross describes the mating of an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype?
testcross
What is the name for a fertilized egg that has two copies of each gene?
zygote