Chromosomal Inheritance Flashcards
what is a pedigree?
chart that diagrams the inheritance of a trait or condition through generations of a family
Humans and other mammals have two types of sex
chromosomes
a larger X chromosome and a smaller Y chromosome
A person with two X chromosomes usually develops anatomy we associate with the…
Female
properties are associated with the inheritance of one X
and one Y…
Male
Gene SRY (sex-determining region on the Y) does what
is responsible for the development of the testes in a developing baby in utero
For a recessive X-linked trait to be expressed:
-A female needs two copies of the allele (homozygous)
-A male needs only one copy of the allele (hemizygous)
What is X inactivation?
one of the two X chromosomes in each cell is randomly inactivated during embryonic development
What does the inactive X condense into
Barr body
What is gene linkage?
the closer the genes are to each other, the more likely they are inherited together
what is an Abnormal Chromosome Number?
of chromosomes taken or given
what is Aneuploidy
abnormal number of chromosomes, less or more than 2
a monosomic zygote is what
has only one copy out of two of a particular chromosome
a trisomic zygote is what
has three copies instead of two of a particular chromosome
Nondisjunction
improper separation during miosis
translocation
switch of large portions of chromosomes
