Chapter 4 Flashcards
Define incomplete dominance and give an example
An intermediate phenotype is expressed (ex: red and white flower make pink flower)
Define codominance
Both alleles and phenotypes are expressed
Chromosomes X and Y are called ________ chromosomes, all other chromosomes are called what?
sex chromsomes; autosomes
Males are more likely to inherit what kind of genetic condition?
X-chromosome linked
Any cell with 23 pairs of chromosomes is ___________; any cell with 23 unpaired chromosomes is _________.
diploid; haploid
Individuals with two identical alleles for a trait are ____________; individuals with two different alleles for a trait are ____________.
homozygous; heterozygous
An allele/ trait that is masked by a dominant trait is said to be what?
Recessive
The two alleles for a trait make up what?
A genotype
Define polygenic inheritance
When genes at 2 or more loci contribute to 1 phenotype
Define pleiotropy
One gene has multiple effects
Define epigenetics
The idea that gene expression can change and be passed down through generations without altering gene structure
Define karyotype
A chart of all 46 chromosomes
Each pair of chromosomes is said to be what?
Homologous
If a dominant allele is silenced and has no effect on some people who carry it, it is said to show ____________ ____________ in that population
incomplete penetrance
What things affect gene expression
1) Environmental factors
2) Nutrition (some genes need enzymes to be expressed)
