Mendelian Genetics Flashcards
What are sex-linked traits?
- Genes inherited on the X/Y chromosomes are sexlinked; other inherited genes in chromosomes are autosomal.
- Y is smaller than X chromosome.
- Y doesn’t have the same amount of genes as X.
- Pattern of inheritance of X chromosomes occurs differently in males and females.
- XX = Female, XY = Male.
Explain the terms co-dominance and Incomplete in genetics.
When neither allele is dominant over the other; in heterozygous genotypes - both phenotypes show the trait. In homozygous genotype - one phenotype shows trait.
Incomplete - parent traits are blended into new trait - (neither parent phenotype is shown).
Co-dominance - parent traits are both expressed as the phenotype of the offspring - in blotches.
What are the two forms of inheritable traits from?
Sexual Reproduction (sperm/egg) - traits inherited via. gametes; possessing a combination of traits from both parents.
Asexual Reproduction (bacteria) - barring mutation; identical clones of the parent, in some exceptions genetic material can be exchanged between clones.
What is a genotype?
Part of the genetic makeup of a cell, and therefore of any individual, which determines one of its characteristics presented through alleles.
Where can genes be located in a chromosome?
Located in the two locus’s of a chromosome for each allele.
What is an allele?
An allele is one of the possible forms of a gene. Most genes have two alleles, a dominant allele and a recessive allele. If an organism is heterozygous for that trait or possesses one of each allele, then the dominant trait is expressed.
What is Monogenetic Inheritance (part of multi-allelic inheritance)?
Multiple allele inheritance involves more than two alleles for a characteristic, but only one pair of alleles is inherited - one shown phenotype.
These show discontinuous variation in the species population (same traits only involving two alleles).
What is Polygenetic Inheritance (part of multi-allelic inheritance)?
A single characteristic is controlled by the alleles of two/more genes (polygenes) located on multiple chromosomes interacting with one another.
Involve more than one pair of alleles for the characteristic & the patterns of inheritance are complex. - continuous variation.
How are Polygenes connected to the environment?
Expression of polygenesis also impacted by environmental factors - with anatomy/features impacted by habitat - resources, exposure, competition, etc.
