SEX RELATED INHERITANCE Flashcards
traits that are limited to only one sex
SEX-LIMITED TRAITS
sex-limited traits are usually
AUTOSOMAL
is a good example of a sex-limited trait that is exclusively exhibited among females.
LACTATION
are autosomal traits that are influenced by sex. If a male has one recessive allele, he will show that trait, but it will take two recessive for the female to show that same trait. One such gene is baldness.
SEX-INFLUENCED TRAITS
are genes found either on X or Y chromosomes which are inherited differences among male and a female.
SEX-LINKED GENES
________________ determined by an X-linked gene when an X chromosome takes control. On the other hand, the so called Y-linked genes are those located on the Y chromosome.
SEX-LINKED TRAITS
The X chromosome is larger than the Y chromosome
X-LINKED INHERITANCE
If the mutated gene is present in the Y chromosome, then this is referred to as
Y-LINKED INHERITANCE
An example of an X-linked trait is a rare genetic disorder in which a person lacks enough blood-clotting proteins caused by a change in one of the genes. Since this phenomenon is sited on the X chromosome, females identified to have affected two X chromosomes cause the disorder. But if there is only one chromosome affected, the female individual is referred to as “carrier” of the disorder.
HEMOPHILIA
Is a Y-linked trait controlled by a Y chromosome and characterized by hairy ear in which are expressed in males alone. This human condition can be inherited from a father who has the disorder, to his sons who, in turn, will pass it on to their sons.
HYPERTRICHOSIS PINNAE AURIS
are at much greater risk for inheriting sex-disorders because they only inherit one X, so if the X has the allele for the disorder, they will become affected.
MALES
who is at greater risk for inheriting sex-linked disorders?
MALES
is a genetic representation of a family tree that diagrams the inheritance of a trait or disease though several generations.
PEDIGREE
PARTS OF A PEDIGREE
- SHAPES
- LINES
- FILLING
- IDENTIFYING INDIVIDUALS
males (pedigree)
squares
females (pedigree)
circles
connect breeding couples (pedigree)
horizontal lines
connect parents to children (pedigree)
vertical lines
means death (pedigree)
diagonal line
means the individual has the trait (pedigree)
shading
means they carry the gene called a “carrier” (pedgree)
half-shading
means the individual does not have the trait (pedigree)
no shading
show generations (pedigree)
roman numerals
assign an individual to a generation and birth order (pedigree)
identifying individuals
