Unit 3: Genetics Flashcards
This deck is designed to assist you in understanding the concepts entailed within Mendelian genetics.
What is a trait? Provide a distinguishing example.
Each variant for a characteristic
Example: Eye color is a characteristic. Blue, brown, grey, or green eyes are traits.
What is a genotype?
Combination of alleles that an individual possesses for a specific gene
What is a phenotype?
An organism’s observable characteristics
Example: Your looks
What is hybridization?
Refers to the process of producing offspring by mating two parents.
Name the list of generations in order.
P-Generation- Parental Generation
F1 Generation- Filial Generation
F2 Generation- Second Filial Generation
What are alleles?
Alternative versions of genes
Examples: RR, rr, Rr
What is a dominant allele/trait?
One variant of a gene on a chromosome masking or overriding the effect of a different variant of the same gene; indicates by capital letters
What is a recessive allele/trait?
This is the variant of a gene that is overridden and whose effect is not visible in the phenotype; indicated by lowercase letters
What is a recessive allele/trait?
This is the variant of a gene that is overridden and whose effect is not visible in the phenotype; indicated by lowercase letters
What is a dominant?
One trait masks or overrides the effect of a different trait of the same characteristic; indicated by capital letters
What is recessive?
This is the trait that is overridden and not visible in the phenotype; indicated by lowercase letters
What is incomplete dominance?
Neither trait is truly dominant and so the phenotype is a mixture of the two traits; is always heterozygous
What is partial dominance/codominance?
Both traits are dominant and both traits will become expressed in the phenotype; is always heterozygous
What does homozygous mean?
Pair of identical alleles
Examples: BB (Homozygous Dominant), bb (Homozygous Recessive)
What does heterozygous mean?
Pair of different alleles
Example: Bb
What is the Punnett square?
Is a square diagram that is used to predict the genotypes of a particular cross or breeding experiment
What are the first three steps of how to make and analyze a Punnett square?
- Determine the genotype of the parents
- Write down the “cross”
- Draw the Punnett square
What are the last four steps of how to make and analyze a Punnett square?
- “Split” the parents’ genotypes into gametes on the outside of the Punnett square
- Determine genotypes of offspring.
- Summarize results (genotypes and phenotypes)
In a Punnett square on the slides, what are the Y and G individually?
The genetic contributions of one parent and the other
In a Punnett square on the slides, what are the YG’s collectively?
The offspring genotype possibilities
How many alleles does an individual have for a gene?
Two each
