Pedigree

(2n-1) Missing a chromosome

(2n+1) Has extra chromosome

Failure of chromosomes to separate
Common during meiosis

One sex chromosome (x or xo)
Sex-Linked Recessive

Males have one Y and two+ X

Females have 3+ X chromosomes

XYY, Males with two Y instead of one

Chromosome 7 deletion

Chromosome 5 deletion

Chromosomes 2 and 20 swap segments

23 pairs of chromosomes
46 total
22 autosomes, 2 pairs of sex chromosomes

Constricted region of linear chromosomes (middle)
They keep chromosomes alignned

Located at ends of linear chromosomes
They protect the ends of chromosomes

Thread-like structures (the X)
Keeps DNA tightly wrapped

Complete set of chromosomes

FIRST total # of chromosomes
THEN sex chromosomes
FINALLY any extra (+) or missing (-) chromosomes

47,XY,+18
46,XX
47,XXY

Two copies of chromosome joined together by centromere

Proteins that package / organize DNA into coiled structures called chromatin

Chromosomes that dont determine sex

Carried on X chromosome and are more common in males than females

The total number of chromosomes in a somatic cell

X-Linked Recessive

X-Linked Recessive

X-Linked Recessive

X-Linked Dominant

One of the parents will have trait
Equally affects both genders
Will not skip a generation
Aa or AA for Females, A for males

Can skip a generation
Neither parent required to have the trait
Both parents are equally likely to be affected
aa for Females, a for Males

One of the parents will have trait
Females most common
Will not skip a generation
XAXa or XAXA for Females, XAY for Males

Can skip a generation
Neither parent required to have the trait
Men most common
XAXa for females, XaY for males