Ch 7. Extending Mendelian Genetics
Terms in this set (56)
Law of independent assortment
When two or more characteristics are inherited, alleles assort INDEPENDENTLY during gamete production, giving different traits an equal opportunity of occuring together
Is the exchange of chromosomes segments during prophase of meiosis I
When does crossing over occur?
Crossing over occurs anytime a germ cell divides
How many alleles are there for every ONE gene?
There are 2 alleles for every 1 gene.
Refers to any mixing of parental alleles, other than crossing over
Chromosomes that determines the sex of an individual
Chromosomes that aren't sex chromosomes (pairs 1-22)
The chromosome that determines if a individual is a male; isn't big enough to carry all the genes that the X chromosome does
Two X's are needed to make an individual a girl; carries the rest of genes
Disorders caused by recessive alleles
2 copies of this allele MUST be present for the person to have the disorder
Is someone who had 1 allele for the disorder and 1 normal allele
Disorders caused by dominant alleles
Only 1 copy of allele must be present for the person to have the disorder
Chromosome that is inherited from the mother
Where are genes located?
Genes are located on the sex chromosomes
What does phenotype depend on?
Phenotype can depends on interactions of alleles
What do traits rely on?
Traits rely on a larger range of dominance
When in a heterozygous individual- there is a BLENDING of traits
Co-dominance is when both alleles are expressed equally within a heterozygous individual
Many genes that interact to produce one gene
Examples of polygenic traits
Skin color, eye color, height
Genes that interfere with the expression of other genes
Involves the same relationships between alleles
Useful chart that is used to trace the phenotype and genotype within a family; can be useful to detect a genetic disorder throughout a family
Half shaded characters on a pedigree
Symbolizes that the male/female is a carrier
Shaded characters on a pedigree
Symbolizes that the male/female has the genetic disorder
a picture of all the chromosomes in a cell
How are chromosomes categorized?
Chromosomes are categorized in order based on their size
A distinguishing characteristics that are inherited
Is the study of biological inheritance patterns and variations within an organism
Mating of two organisms
Law of segregation
Organisms inherit 2 allele copies of each gene (one from each parent); Organisms donate only one copy of each gene in their gametes thus, the two copies of each game segregates during gamete formation
A piece of DNA that provides a set if instructions to a cell to make a certain protein
2 same alleles at a specific locus
2 different alleles at a specific locus that codes for a different trait
Refers to the genetic makeup of an individual
Refers to the physical traits of an individual
The trait is only expressed when two copies are present
Punnet Square; there are two alleles per box
Are inherited through sexual reproduction because, the trait is located in the sex chromosome
A cross between an organism with a known genotype with an organism with an unknown genotype
Interaction of environmental
Genes might show differently based on environment and the phenotype can also be affect
Sex-linked genetic disorder that prevents blood form clotting properly
Genetic disorder caused by dominant alleles
A disorder caused by recessive alleles
When one X chromosome is randomly turned off
The allele that expressed when the two alleles are different
all the organism's genetic material
the likelihood that a particular event will happen
Number of ways a specific event can occur/ number of total possible outcomes
genes located close together that tend to be inherited together
Example of a polygenic trait
human eye color
If a male has a disorder located on the X chromosome, would the male be carrier?
No, if a male has a disorder located on its X chromosome, the male will have the disorder
Which gender expresses sex-linked traits more frequently in their phenotype?
A person who doesn't express autosomal trait has what type of genotype?