Genetics Vocabulary
What is a phenotype?
Physical Traits
Mendel crossed peas that were round and wrinkled. All of the offspring were round. He then crossed the F1 generation round peas. What phenotype is dominant?
round peas
Draw a Punnett square to determine the percent of heterozygous individuals when there is a cross between AA x aa individuals.
100%
In chickens, black bodies are C1C1 and white bodies are C2C2. If I cross a black and white chicken what will all my offspring look like if the trait is inherited codominantly?
Black and white
What kind of cells go through meiosis?
Gametes or haploid cells
What is a genotype?
Genetic makeup, usually represented by letters
When Mendel completed a dihybrid cross with heterozygous tall and round plants, what was the least common phenotype?
The recessive phenotype (short & wrinkled)
DD, Dd
DD, Dd
These are the Punnett square results. What phenotypes will be shown in the offspring? (use words like dominant and recessive)
All offspring will show the dominant phenotype
A and B blood are codominant. What is the phenotype of a person with the genotype IAIB?
AB (Both A antigens and B antigens showing)
What is the end result of meiosis?
4 genetically different haploid cells
What is the difference between heterozygous and homozygous?
heterozygous have different alleles, homozygous have the same alleles
How many different gametes can be produced by a tall and purple flowered pea plant? The genotype of the pea plant is TtPp
4
What percent of individuals will be homozygous recessive if there is a cross between two heterozygous individuals, Aa x Aa? Draw a Punnett square to help.
25%
There are 2 genotypes that can produce the phenotype of type A blood. What are they?
IBIB or IBi
What happens during metaphase I?
Homologous chromosomes line up at the center of the cell
What is the difference between codominance and incomplete dominance.
Codominance is when both alleles show (ex. black and white feathers), incomplete dominance is when the traits blend (Red and white make pink)
Mendel crossed peas that were round and wrinkled. All of the offspring were round. He then crossed the F1 generation round peas. What did Mendel see in the F2 generation?
3/4 were round and carry the dominant allele for roundness, and 1/4 were wrinkled.
If the offspring have the following probabilities, what were the genotypes of the parents?
1/4 - TT, 1/2 - Tt, 1/4 - tt
Tt (heterozygous) for both parents
In flowers, petal color follows incomplete dominance where the two alleles are red (R) and white (W). If I cross two heterozygous pink plants, what percentage of offspring will be pink?
50%
Which event occurs in prophase I of meiosis, but not in mitosis?
Homologous chromosomes pair up into tetrads, where they cross-over gentic material
What is the difference between diploid and haploid cells?
diploid cells have two sets of each chromosome while haploid only have 1 set
What gametes can be produced with the parent with the following genotype YyPp?
YP, Yp, yP, yp
A yellow seeded, purple flowered heterozygous plant (YyPp) is crossed with a green seeded, white flower plant (yypp). (Y = yellow seed allele; y = green seed allele; P = purple flower allele; p = white flower allele)
What is the probability that an offspring of this cross produces plants with green seeds and white flowers
4/16
A person with type A blood and a person with type B blood had a child with type O blood. How is this possible?
Both parents must have been heterozygous (IAi and IBi) and both gave the recessive allele to the offspring to give them ii, making type O blood
Both the traits for petal shape and flower color can be found on the same chromosome for the windflower. A windflower has one chromosome that has the alleles for round petals and red color, while the other chromosome has the alleles for star shaped petals and pink color. Is it possible that the flower could have offspring that are round and pink? Explain.
Yes, the alleles could switch during prophase I in a process called crossing-over