Bio genetics

The father of genetics

Gregor Mendel

how is DNA passed

Passed through cell division and is then passed down each generation

Gene

sequence of dna that codes for a specific protein or trait

homologous chromosomes

matching pairs of chromosomes

Allele

genetic traits all have different versions

dominant

stronger allele only one is need to show

recessive

“weaker” allele that takes two copies to show

genotype

you have two copies per gene since you inherit two copies of each chromosome.

homozygous dominant

BB

Heterozygous

Bb

homozygous recessive

bb

penotype

what is actually shown for the genotype

Meiosis

A special type of cell division that creates reproductive cells

what does meiosis produce?

gametes

diploid cells

full set of chromosomes, typically body cell and chromosome

haploid cells

The original chromosome number

why is it important to halve chromosomes

everyone is unique and different from each other.

meiosis I

homologous chromosomes separate

meiosis II

sister chromatids separate

how many cells are produced in meiosis

a total of 4 daughter cells

crossing over

genetic shuffle. chromosomes physically exchange segments

importance of meiosis

enables sexual reproduction. creates genetic variation. prevents chromosomes numbers from doubling. supports evolutionary adaptation.