Connect 1 Genetics
A Punnet square is a tool that can be used to predict the expected ratios of a genetic cross. What are the steps of construction and using a punnet square in the correct sequence, starting at the top
1. Determine the genotype of each parent 2. List all the gametes possible from each parent 3. Create a Punnet square with the gametes of one parent listed as the column headers, and the gametes of the other parent listed as the row headers 4. Determine possible offspring genotypes by filling each empty box with the symbols from the row and column headers 5. Analyze the relative proportion of each genotype and phenotype of the offspring
A pea plant can have either yellow or green seeds and pods. Seeds will be yellow if it has at least one yellow seed allele in its genome. A plant will have yellow pos only if it has two alleles for the yellow pid phenotype. What conclusion can be drawn based on this information?
1. Green is recessive to yellow for the trait of seed color 2. Yellow is recessive to green for the trait of pod color
Which of the following were crucial components of Mendel's quantitative approach?
1. He worked with a large number of plants 2. He counted all the offspring of a cross
Which of the following are gametes?
1. Sperm 2. Eggs
Consider a dihybrid cross where the true-breeding parents are tall pea plants that produced 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?
1. Tall plants with white flowers 2. Short plants with purple flowers
What gametes will be produced by an organism with the genotype Tt?
1/2 T & 1/2 t
If a parent with the genotype AaBb mates with a parent who is aabb, what is the probability of an Aabb offspring?
1/4
If you cross a pea plant with wrinkled yellow seeds (rr Yy) to a plant with round green seeds (Rr yy) what would be your expected phenotypic ratio among the progeny?
1:1:1:1
What is the expected phenotype ratio among the progeny when a plant that is heterozygous for alleles controlling two traits is allowed to self fertilize?
9:3:3:1
What is the expected phenotypic ratio among the progeny when a plant with the genotype RrYy is allowed to self fertilize?
9:3:3:1
What is a monohybrid cross?
A cross involving a single trait
What is the basic unit of biological information?
A gene
Different alleles of a single fly gene control white or red eyes. A fruit fly carries one allele for white eyes and one allele for red eyes. This fly is ________
A monohybrid
Determine the possible gametes that could be formed from an organism with the genotype Aa Bb
AB Ab aB ab
Determine the possible gametes that could be formed from an organism with the genotype AABbCc
ABC ABc AbC Abc
For Mendel's pea plants, the tall phenotype is determined by a dominant allele and the dwarf phenotype is determined by a recessive allele. In the first of F1 generation, what is the outcome of a cross between true-breeding tall (TT) and true-breeding (tt) plants?
All of the offspring will be tall
A pea plant required 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?
All of them: 1. The non-functional allele is most likely recessive to the normal allele. 2. The allele for the white flower phenotype is most likely to recessive to the normal allele.
Which of the following represent heterozygous genotypes?
All of these: 1. Bb Cc 2. Cc
Two plants have different forms of a gene that determines pea and pod color. One plant has yellow pods, and the other green. What are the different forms of the pea pod color gene called?
Alleles
Which letter denotes the F1 generation?
B
A true-breeding tall pea plant with purple flowers is crossed with a true-breeding short pea plant with white flowers and the offspring are allowed to self-fertilize. This type of cross is a ______
Dihybrid cross
If a genetic study began with your grandparents, which generation would represent you and your siblings?
F2
The genetic composition of an individual is the ____________
Genotype
What term describes an individual's combination of alleles?
Genotype
An organism that has two different alleles for a specific gene, is ________
Heterozygous
What is the term that described an individual that has two identical copies of a gene?
Homozygous
In his experiments, Mendel studied _______, or offspring he produced by cross-fertilizing plants that exhibited antagonistic pairs of traits (for example yellow versus green seeds)
Hybrids
The alleles of two different genes will be distributed randomly into gametes. This statement summarizes which of Mendel's laws?
Law of independent assortment
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
An organism's genotype is RrYy and it produces gametes with the genotypes RY, Ry, rY, ry with equal frequency. Which of Mendel's laws explains this fact?
Mendel's law of independent assortment
Experiments involving hybrids for a single trait, flower color, are called __________
Monohybrid crosses
Define recombinant types
Offspring who have inherited new combinations of genes and have phenotypes that don't match either parental phenotypes.
In one of his experiments, Mendel started by crossing pure-breeding tall pea plants with pure breeding short pea plants. These pure breeding plants are considered the ________ generation
P
Consider a dihybrid cross where the true-breeding parents are tall pea plants that produce purple flowers, and shirt 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
The color and pattern of fur is controlled bu genes. A dog has fur that is white with black spots. Does this description refer to the dog's genotype or phenotype?
Phenotype
What term describes the observable characteristics that result from the expression of a gene?
Phenotype
One limitation of selective breeding prior to Mendel's wok was the inability to _____
Predict when offspring would inherit a valuable trait
The expected outcome of flipping a coin is 50% heads up and 50% tails. However, in a given study, the coin toss yielded heads 65% of the time and tails 35% of the time. What are the accounts for this discrepancy?
Random chance
When a preexisting allele is changed to a version that no longer codes of a functional protein, the new allele i likely to be _______ to a normal allele
Recessive
The two gametes prodded by an organism with the genotype Tt are _____ and ________
T t
A tall pea plant with axial flowers has the genotype TT AA. What gametes can this plant produce
TA
A tall pea plant with axial flowers has the genotype Tt Aa. What type of gametes can be produced by this plant?
TA, Ta, tA, ta
What typeof 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
A male has the genotype TT and a female parent has the genotype Tt. How would the punnet square for this cross be set up?
The male gametes T and T would be placed as the header of the columns and the female gametes T and t would be placed as the headers of the rows
The probability of two or more independent events occurring together is calculated by multiplying the probability of each event. This is known as ______
The product rule
A pea plant will be tall if it has at least one tall allele in its genome. A plant will be dwarf only if it has two alleles for the dwarf phenotypes. What conclusion can be drawn based on this information?
The tall allele is dominant to the dwarf allele
For Mendel's pea plants, the tall phenotype is determined by a dominant allele and the dwarf phenotype is determined by a recessive allele. Suppose there is a cross between true-breeding dwarf plants. What is the expected outcome in the second or F2 generation when F1 plants are crossed to each other?
Three-fourths of the offspring will be tall and one-fourth of the offspring will be dwarf
What is the purpose of preforming a test cross?
To determine the genotype of an organism expressing the dominant phenotype
Which of the following would be classified as the P generation?
True-breeding parents that are crossed
What is the name for a fertilized egg that has two copies of each gene?
Zygote
The offspring of a pea plant with purple flowers and a pea plant with white flowers would be called ______
a hybrid
The offspring of a pea plant with purple flowers and a pea plant with white flowers would be called _______
a hybrid
An organism with one dominant and one recessive allele for a single trait is
a monohybrid
The term that describes an alternative form of a gene is _______
allele
Many food crops, such as corn and potatoes, were developed by using seed from the best tasting plants for the next planting in progress is a process called
artificial selection
What is a monohybrid cross?
cross involving a single trait
When the presence of a single character of a trait is sufficient for the expression of that character, it is called a ________
dominant character
A _____ is a specialized cell that carries a single copy of each gene to the next generation
gamete
The _______ is the basic unit of biological information
gene
If an organism has two identical allele of a particular gene, it is said to be _________
homozygous
The product rule can be used to ___________
predict the probability of two or more independent events
A character that is masked by another character but reappears in subsequent generations is
recessive
_________ - fertilization is a cross in which the pollen and the egg come from the same plant
self
A cross in which the pollen and egg come from the same plant is called ______
self-fertilization
A line of peas that, when allowed to self-fertilize, produces the same type of offspring generation after generation is called an
true/pure breeding line
A _____ is formed when a sperm fertilizes an egg, creating a cell with two copies for each gene
zygote