Genetics and Inheritance Flashcards
(23 cards)
Mendel’s Experiments
The Laws of Probability
Law of Dominance and uniformity
Some alleles are dominant while others are recessive; an organism with at least one dominant allele will display the effect of the dominant allele.
Law of Segregation
During gamete formation, the alleles for each gene segregate from each other so that each gamete carries only one allele for each gene.
Law of Independent Assortment
Genes of different traits can segregate independently during the formation of gametes.
Dominant Traits
are those that are inherited unchanged in a hybridization
Recessive Traits
latient; or disappear, in the offspring of a hybridization
Alleles
Gene variations arise by mutations and relative locations on homologous chromosomes
Dominant
One allele that prevents a second allele from affecting the phenotype when the two alleles are paired together
Recessive
an allele that has no effect on the phenotype when paired with a dominant allele
Homozygous
The genotype consists of two copies of the same allele Example: BB or bb
Heterozygous
The genotype consists of two different alleles example Bb
Phenotype
The physical expression of a given trait
Genotype
The pair of alleles for a given trait
Physical traits
Easily observable traits
Biochemical traits
often more difficult to observe
Behavioral traits
behaviors with some genetic basis
Punnett Square
a grid-like diagram used to predict the results of a genetic cross
The Laws of segregation
The two alleles of a gene end up in two different gametes egg or sperm cells
The law of independent assortment
When gametes form, the two alleles of any given gene segregate during meiosis independently of any two alleles of other genes
Mendelian Traits
traits controlled by a single gene and unaffected by environmental conditions
Complex traits
a genetic trait whose pattern of inheritance cannot be predicted by Mendel’s laws of inheritance
Polygenic traits
single traits governed by more than one trait
