genotype, phenotype and inheritance Flashcards
define genotype
the genetic make up of an individual
define phenotype
the observable characteristic determined by interaction of the genotype with the environment
define allele
a form of a gene
define homozygous
2 alleles of a gene the same
define heterozygous
2 alleles of a gene different
define hemizygous
only 1 allele of the gene on the x chromosome
males only
define what a dominant allele is
allele that determine the phenotype in a htz
define what a recessive allele is
non-dominant allele in a htz
what is co dominance? give an example
when both alleles of the gene are expressed creating an intermediate phenotype
blood group - A + B both dominant over O
when A + b alleles present both expressed to AB group, show co dominance
What is a male on family tree?
square
What is a female on family tree?
circle
What show a carrier on a family tree?
half shading
What shows an affected individual on a family tree?
full shading
What shows a deceased individual on a family tree?
line through circle/square
What is autosomal recessive inheritance? Give an example of a disease inherited in this manner
only hmz affected
htz carriers
cystic fibrosis
