Karyotypes Flashcards
Karyotypes
photographs of chromosomes organized in homologous pairs
What do typical karyotypes look like?
There are 23 pairs of chromosomes and each pair has 2.
What do atypical karyotypes look like?
One pair out of the 23 pairs is missing or has an additional chromosome
What are chromosomes are pairs 1-22 called?
Autosomes
What are the chromosomes in the 23rd pair called?
Sex chromosomes
Autosomes
chromosomes that do not determine the sex of an organism
Sex chromosomes
chromosomes that do determine the sex of an organism
Nondisjunction
the failure of chromosomes to separate normally during meiosis
What is the effect of nondisjunction occuring?
the gametes will have a missing or additional chromosome. so when a zygote is made, the zygote will have one less or one more than what its supposed to have
Results of nondisjunction
monosomy or trisomy
Monosomy
when a zygote contains 45 chromosomes due to one of the gametes having a missing one
Trisomy
when a zygote contains 47 chromosomes due to one of the gametes having an extra chromosome
Chromosomes of a biological male
XY
if there is a Y and it is definitely a male
Chromosomes of a biological female
XX or X
as long there is no Y
A sperm contains…
an X OR a Y