Variation and inheritance Flashcards
what are genes
genes are sections of DNA that code for proteins
combining genes from two parents contributes to variation within a species
what are genes
genes are sections of DNA that code for proteins
combining genes from two parents contributes to variation within a species
what are the two types of variation
discrete variation
continuous variation
what are the two types of variation
discrete variation
continuous variation
describe discrete variation
characteristics are controlled by one febe and measurements gal into distinct groups and categories
ur eye colour blood group and tongue rolling
describe continuous variation
characteristics are controlled by more than one gene ( polygenic inheritance ) and measurements show a range of values between a minimum and maximum
ie height and hand span
describe genes
a gene is a short section of DNA which coded for a protein
what are alleles
diffrent forms of the same gene
describe a genotype
the alleles an organism has for a particular characteristic
describe phenotype
the physical characteristics displayed by the organism
describe dominant alleles
always shows in the phenotype if it is present in the genotype
describe recessive alleles
masked by the dominant allele
must inherit two recessive alleles to show the recessive phenotype
describe heterozygous
the genotype contains two different alleles for a particular gene
homozygous
the genotype contains two of the same alleles for a particular gene
what is a monohybrod cross
a genetic cross involving only one characteristic
