Test 1 Flashcards
Define allele
different versions of the same gene
Define genotype
the combination of alleles at a gene or at any number of genes
Define phenotype
the expressed traits of the organism
Define DNA
the genetic material used for all living things
What were the three observations that formed the field of genetics?
Species of organisms, variation within species, trait values are inherited
Members of the same species have the _______ genes at _______ on the _____
same genes at the same location on the same chromosomes
What are the three factors that make up a mode of inheritance?
Number of genes, number of alleles (versions of genes), relationship between alleles
What makes up a phenotype?
genotype and environmental influences (strength varies)
Define Purebreeding
Always produce progeny with the same trait value when selfed
List the traits that made Pisum Sativum an excellent choice for the study of simple genetics
Variation of traits
Abundant progeny
Short life cycle
Easily controlled matings
What are the 7 traits of Pisum Sativum?
Seeds- Round or Wrinkled
Seeds- Green or Yellow
Pods- Inflated or Pinched
Pods- Green or Yellow
Petals- Purple or White
Flowers- Axial or Terminal
Stems- Long or Short
Describe the particle theory of inheritance
Mendel created to explain what he saw, went in contrast to the theory of “blending”.
Particles (genes) are inherited unchanged from each parent to offspring and every individual harbors two particles
What was Mendel’s First Law?
Alleles of a gene pair segregate into gametes
What was Mendel’s Second Law?
Alleles of a gene pair segregate into gametes independently of the alleles of a second gene pair
Homozygous Dominant and Homozygous Recessive cross
What is the F1?
F1 all dominant, hybrid
Homozygous Dominant and Homozygous Recessive cross
What is the F2?
F2 three to one ratio phenotype, 1:2:1 ratio genotype
How do you test cross?
Cross with homozygous recessive. Will get either all dominant, all recessive, or half and half
How do you find the fractional chance of getting a specific multiple trait genotype?
Multiply the odds of getting the first trait by the odds of getting the second trait
Results with Heterozygous - Heterozygous cross (one trait)
Phenotype: 3 to 1
Genotype: 1:2:1
Results with Heterozygous - Heterozygous cross (two traits)
Phenotype 9:3:3:1 (both:one:one:neither)
Genotype: 1:2:1:2:4:2:1:2:1
How do you find the genotype ratios of crosses with multiple traits?
Multiply chance of one specific genotype (Ex: homozygous round) by chance of another specific genotype (Ex: homzygous yellow). The three possibilities (homozygous dominant, heterozygous, homozygous recessive) should all be multiplied by each other. This will yield the fraction chance of getting each specific genotype
What is the equation for finding the amount of f1 gametes, f2 genotypes, and f2 phenotypes for varying numbers of genes?
n is the number of genes
For finding the number of F1 Gametes: 2^n
For finding the number of F2 Genotypes: 3^n
For finding the number of F2 Phenotypes: 2^n
What is Probability for this class?
The number of specific possible outcomes/number of total possible outcomes
What is the Sum Rule?
(Probability 1 + Probability 2) - Probability of both
When do you use the Sum Rule?
Finding the probability of either X or Y. Need to consider whether outcomes are mutually exclusive to determine whether or not to subtract
What is the Product rule?
Probability of 1st event * Probability of 2nd event…