Chapter 2 Flashcards
What is self fertilization
When pollen or an egg is derived from the same plant
What is cross fertilization
When a pollen/egg are derived from different plants
Requires removing and manipulating anthers
What is a hybrid
When two plants differ in a particular trait they create a hybrid
What is a character
An observable characteristic of an organism
What is a trait or variant
Specific properties of a character
Eye color is the trait and blue is the variant
What is a true breed
When a variety produces the same trait over several generations
What is a single factor cross
When only one trait is crossed such as dwarf and tall in height
What is the particulate theory of inheritance
Things that determine traits are inherited as descrete units and remain unchanged as they are passed down
This is the same way to say a gene
What is the law of segregation
Two copies of a gene separate from each other during the process that creates gametes (meiosis)
What is an allele
Different versions of the same gene
What is a normal genotypic ratio and what is a normal phenotypic ratio
Genotype- 1:2:1
Phenotype 3:1
What is a two factor or dihybrid cross
Crossing individual plants that differ in two different characters
The pea plants being round or wrinkled and yellow or green
What is linked assortment
You get your parents genes exactly
50 percent chance to be either parent
What is independent assortment
Supports non parental genotype
Alleles separate when being passed to the offspring there is no longer a guarantee that the offspring will be just like their parents but rather that they inherit some genes from both
What contradicts the linked assortment theory
Non parental because there was proof that some traits can arise without seeing them in the parents
What is the predicted phenotypic ratio for a dihybrid cross
9:3:3:1
What is genetic recombination
When an offspring receives a combination of alleles that differ from the parental generation
Due to independent assortment and crossing over
What are loss of function alleles
Defective copies of genes usually inherited in a recessive manner
How can you determine an autosomal recessive trait pattern
Males and females equally affected
Affected offspring have unaffected parents
Is unaffected parents have affected kids they are heterozygous
Affected kids are homozygous
How can you determine an autosomal dominant trait
Makes and females equally affected
Affected offspring have at least one affected parent
Affected offspring are heterozygous and unaffected offspring are homozygous recessive
How to determine an X linked recessive trait pattern
Males affected more than females
Traits never passed from father to son
Affected sons usually have a carrier mother
How can you determine an X linked dominant trait
Males and females equally affected
Affected sons have affected moms
All daughters of an affected father are affected
