*Mendelian genetics Flashcards
Define Mendelian traits
Characteristics that are influenced by alleles at only one genetic locus (location on the chromosome)
-Most mendelian traits aren’t physical (phenotype)
Examples; many genetic disorders such as the presence of many blood types, sickle cell, and anemia
Define principle of segregation
genes occur in pairs
define recessive
an allele in the hetrozygotes pair that isn’t expressed. For it to be expressed their needs to be two copies (homozygotes)
Define dominant
the allele that is expressed in the presence of another allele. Dominant alleles prevent the recessive allele from showing.
Define alleles
you’re genes. They influences your traits. Located on the chromosome
Define locus
the position on the chromosome where the allele is
define homozygous
having the same allele (both parents have brown eyes)
define phenotype
physical expression of the gene.
define genotype
an individuals genetic makeup
Most Mendelian traits are what kind of allele?
Harming biochemical alleles
define co-dominance
an expression of two alleles in a heterozygous pair
-neither is dominant or recessive, they both show
example; your blood type
define structural genes?
Contain information to make a protein
Define Regulatory Genes?
genes that guide the expression of structural genes.
Having an 0 blood type means that you miss what in your allelle?
It means an absence of the protein in the allelle
What causes obesity?
Complex interaction between genes, environment and phenotypes
What did Gregor Mendel discover?
Basic principles of inheritance
What’s the law of independent assortment?
alleles separate independently from one another
Define sex linked genes
some traits are linked together and tend to be inherited together. Most sex linked genes are carried on the X chromosome.
Define mutation
any change in a DNA sequence that becomes established in a daughter cell
define point mutation
mutation that occurs when a single base is changed (not both pairs)
Example sick cell anemia
What happens when a good mutation occurs?
It increases the organisms ability to survive and reproduce
Mutations are a source of variation - no variation, no natural selection!
Define Concordance.
To share a trait - such as allergies in twins.
What are polygenic Traits?
Continuous traits. eg- Hair colour, eye colour, weight. Some of these traits interact with the environment - like weight.
