genetics Flashcards
Mendels first law of segregation
Alleles That encode for the same trait segregate
recall: homologous chromosomes seperate during the meiosis I
Mendels second law independent assortment
Different chromosomes seperate independent of each other
Name the conditions of the Hardy-Weinburg equillibrium
1) random mating
2) no mutations
3) isolated
4) large population
5) no selective pressures
What is the formula for Hardy-Weinberg equilibrium?
p^2 + 2pq + q^2 =1
p= Dominant allele q= recessive allele
What is recombination?
In meiosis crossing over happens and linked traits get seperated into different gametes
further recombination happens in the gamete fusion
*the closer two traits are on a chromosome the less likely they will separate
What is a point mutation?
Change in a single base pair of a gene
What is a deletion?
removal in a sequence of DNA on a gene
What is translocation?
when a chromosome breaks and pairs with another
What is a duplication?
sequence of repeated DNA
What is a frame shift mutation?
shift in the triplet reading frame
What is a mutagen?
a substance that cause a mutation
What happens in meiosis?
The chromosome is reduce from diploid 2N to haploid N
What happens in prophase I?
1) the chromosome appear
2) nuclear membrane and nucleoli disappear
3) Spindle fibers organize
4) synapsis (pairing of homologous chromosomes
5) crossing over (chiasta form)
What happens in metaphase I?
1)the synaptic chromosomes line up at the equitorial plate
What happens in anaphase I
1) homologous chromosomes migrate to opposite sides of the spindle
centromeres do not divide
