The Work of Gregor Mendel
The scientific study of heredity.
What is genetics?
The likelihood that a particular event will occur.
What is probability?
A red flower is crossed with a white flower. The offspring are all pink. The inheritance pattern demonstrates this genetic phenomenon.
What is incomplete dominance?
Mendel used these plants in his experiments because they were easy to grow and had many contrasting traits.
What are pea plants?
A specific characteristic, such as flower color or plant height.
What is a trait?
What country is Gregor Mendel, the father of genetics, from?
What is Austria?
The physical characteristics of a living organism are called this.
The genetic makeup of a living organism is called this.
What are phenotype and genotype?
In a dihybrid cross of two heterozygous pea plants (RrYy x RrYy), Mendel observed a 9:3:3:1 phenotypic ratio. The alleles for different traits separate according to this principle.
What is independent assortment?
The first generation produced from crossing two parent plants was called this.
What is the F1 Generation?
Mendel concluded that each trait is controlled by these inherited factors.
What are genes?
Plants that consistently produce offspring with the same traits when self-pollinated are called these.
What are true breeding plants?
The expected genotypic ratio resulting from a Tt x Tt cross is this.
What is a 1:2:1?
A rabbit species has four coat color alleles with this dominance hierarchy:
C > cc h > ch > c
This best demonstrates this genetic concept.
What are multiple alleles?
Reproductive cells are also called this.
What are gametes?
An allele whose trait is always expressed when present.
What is a dominant allele?
Mendel crossed a true breeding tall plant (TT) with a true breeding short plant (tt). The genotype of all F1 offspring was this.
What is heterozygous (Tt)?
The reason a Punnett square cannot guarantee the exact outcome of a genetic cross, even when probabilities are know.
What is Punnett squares predict probabilities and averages, not the exact results of individual offspring?
One parent has blood type A, while the other parent has blood type B. Their child expresses both A and B antigens on his red blood cells. The pattern of inheritance is best describes as this.
What is codominance.
The reappearance of recessive traits in the F2 generation provided evidence for this principle.
What is segregation?
In a Tt x Tt cross, this genotype occurs most frequently.
What is Tt?
TT = 25%
Tt = 50%
tt = 25%
A student claims that alleles for shortness disappeared in the F1 generation because all of the offspring were tall. Mendel would explain that the allele was actually doing this.
What is remaining present but masked by a dominant allele?
A scientist performs 400 offspring from a Tt x Tt cross and observes a 3:1 ratio. Give the correct number of tall plants and short plants based on the given ratio.
What is 300 tall and 100 short?
A geneticist studies human skin color and finds that variation results from the combined effects of several genes, while sunlight exposure also influences the final phenotype. Name the two concepts that explain these observations.
What are polygenic inheritance and gene-environment interaction?
A pea plant produces gametes carrying only T alleles. From this information alone, you can conclude that the plant is this.
What is homozygous dominant (TT)?
Mendel's experiments supported the idea that inheritance is not a blending of traits because this trait reappeared unchanged in later generations.
What is the recessive trait?