Inheritance (BIOL4) Flashcards
Define alleles
Different versions of a gene
Define genes
Sequence of bases on a DNA molecule, codes for protein which results in a characteristic
Define genotype
Genetic constitution of organism - alleles organism has
Define dominant
Allele who characteristic appears in phenotype, when only one copy present
Define recessive
Allele whose characteristic only appears in phenotype if 2 copies present
Define codominant
Alleles both expressed in phenotype, neither recessive
Define locus
Fixed position of gene of chromosome
Define homozygote
Organism that carried 2 copes of SAME allele
Define heterozygote
Organism that carried 2 DIFFERENT alleles
What are genetic diagrams used for?
To predict genotypes and phenotypes of offspring
Define monohybrid inheritance
Inheritance of single characteristic controlled by different alleles
Features of sex-linked characteristics
- Genetic info for gender carried by 2 sex chromosomes
- Females XX; males XY
- Characteristic is sex-linked when allele that codes is located on sex chromosome
- Y chromosome smaller - carried smaller genes; most genes carried on X chromosomes
- Males only have 1 X chromosomes - only have one copy to express characteristic
- males likelier to show recessive phenotype for genes that’s sex-linked
Features of genes with multiple alleles
More than 2 alleles on same gene
ABO blood group system have 3 alleles for type
ABO blood group system
IO - blood group O
IA - blood group A
IB - blood group B
IO recessive IA and IB codominant –> IAIB = blood group AB
What are Genetic Pedigree diagrams used for?
To show traits within a family Show inherited trait
