BIO TEST 1 Flashcards
what is an allele
diffrent versions of the same gene
what is homozygus
when an organism has 2 of the same alleles (pure breed)
what is heterozygus
when the organism has 2 diffrent allele (cross breed)
what is a recessive gene
the ‘hidden’ not dominant gene. ( the lower case allele)
what is genotype
what the organisms alleles are
what is a phenotype
what the organism appears as, its characteristics , looks
what is a sex linked trait
when a characteristic is either on the X or Y chromosome
what is incomplete dominance
when both genes contribute to the phenotype
what is the diffrence beyween an allele and a gene
A gene is a specific segment of DNA with the code for particular characteristics e.g pea pod colour, Alleles are diffrent forms of this gene e.g allele for green pod, allele for yellow pod
why are punnet squares used
to solve genetic problems
who devised punnet squares
reginald punnet
why did Mendels experiments show good experimental method
used a large sample size, kept accurate records, analysed results, controlled numer of variables, repititiony
why is mendel known as the father of genetics
he discovered the laws of inheritence
fossils other than bone
plants, wood,feathers, poo, fur, foot prints, sea floor, burrows, shells, teeth
Darwins theory of evolution
varition occours randomly amoung members of a species. individaual traits could be inherited by its offspring. struggle for existance allows those with favorable traits to survive
