chromosomes

heterochromatin is

transcriptionally inactive

euchromatin is

actively transcribing

aneuploidy

individuals have one extra or one less chromosome; caused by nondisjunction

turner syndrome

X

klinefelter

XXY

polyploidy

individuals have 3 or more of each type of chromosome

x-linked disorders in males

color blindness, hemophilia, muscular dystrophy

telomeres are found at the ends of chromosomes,

contains repeated nucleotide sequences (rich in guanine)

teleomeres protect DNA

from digestive enzymes

telomeres: each time a DNA molecule is replicated some DNA is lost from

the ends of the chromosomes

telomerase adds multiple copies of the same

telomere DNA sequence to the end of the chromosomes