Unit 3.8 - Genetics Flashcards
What are molecular genetics?
It is the study of specific genome traits.
What are chromosomes?
There are 46 in the body. There are 23 from sperm and 23 from ovum. The bands, known as alleles, code for traits.
How many times are genetic codes coded?
Traits and alleles are coded twice. They are called genotypes.
What are genotypes?
The genetic code. Either homozygous or heterozygous.
What are phenotypes?
Phenotypes are the visible manifestation of the trait.
What are dominant traits?
Alleles that have more influence on the phenotype, chemically more potent and stronger. Darker hair, rolling tongue, hitchhiker thumb, detached earlobes, freckles, dark hair and eyes.
What are recessive traits?
Alleles that have less influence on phenotypes and are less chemically potent. Includes straight hair, light hair, light eyes, and attached ear lobes.
What is incomplete dominance?
It is heterozygous, and blended phenotype. Not recessive more dominant. An example includes wavy hair, medium complexion, hazel eyes. Red flower and white flower = pink flower.
What is co-dominance?
It is heterozygous and non-blended. Both are visible. Examples include heterochromatic eyes, asymmetrical ear lobes, etc.
What are polygenic traits?
These are behaviour genetics and cannot be coded on one pair of the alleles, it is through out the gene. This includes intelligence, depression, personality, criminal behaviour.
How are polygenic traits measured?
Through family studies, adopted studies, and twin studies.
What are family studies?
Compare parents to children and find a large sample correlation, ex. IQ. Nature vs. nurture dilemma involved.
What are adopted studies?
Comparison of biological parents and children vs. adoptive parents and children.
What are twin studies?
It is the study of identical twins - which share DNA and prenatal environment non-twin siblings. It is study of fraternal twins who share same prenatal environment. Included study of adopted identical twins, which grew up in different households but had same preference and hobbies.
