17.1 Studying inheritance Flashcards
What is the genotype of an organism
The genetic makeup of an organism
It is all the alleles of an organism contains
What does the genotype determine
The limits within which the characteristics of an organism may vary
What is phenotype
Physical characteristics of an organism
What is the phenotype a result of
Genotype expression and interaction with the environment
What is a gene
A section of DNA that codes for a polypeptide
What is an allele
A variation of a gene
How do chromosomes occur in diploid organisms
In pairs, called homologous chromosomes
What are homologous chromosomes
A pair of chromosomes, one maternal and one paternal with the same gene loci
If the alleles are the same what is it called
Homozygous
If the alleles are different what is it called
Heterozygous
What is heterozygous
The two alleles present are different
What is homozygous dominant
The two alleles present are dominant
What is homozygous recessive
The two alleles present are recessive
What is co-dominance
In which two alleles contribute to the phenotype
What are the two things that co-dominance can do to the phenotype
- The phenotype is either a blend of the two alleles. e.g. Red + white = pink
- The phenotype contains both, e.g. blood type AB
