Lecture 3 Flashcards
What is a karyotype?
Our genetic makeup (23 pairs of chromosomes, 22 pairs and 2 sex chromosomes)
What happens when the sperm and egg cells combine? (23 single chromosomes)
Creates brand new DNA codes-not exact replicas of mom and dad so, therefore, there’s an infinite combo of traits!
How many alleles does a pair of chromosomes have?
Two
What is the difference between homozygous and heterozygous?
Homo-both allele pairs match
Hetero-Allele pairs are different
What is genotype?
The DNA coding of alleles
What is phenotype?
How an allele is manifested
What happens when an allele set is heterozygous?
The phenotype reflects the dominant allele
What is incomplete dominance?
When the 2 heterozygous alleles influence the phenotype in a blended way
What is co-dominance?
Two heterozygous alleles influence the phenotype in a non-blended way (BUT does not include skin tone or freckles) an example is calico cats.
Why do we use genetics in psychology?
To understand prediction of traits and fatal diseases-example: developmental disorders, personality traits, intelligence, aggression.
How can the sex chromosomes influence a woman’s pregnancy?
Lots of women have miscarriages based on the gender of the baby (if a woman has lots of girls, a higher chance of miscarrying a boy)
What is Huntingons disease?
Dominant disease, leads to death in 40s, easily passed on because people have children before they’re 40. Neurological degeneration (memory, sight, hearing loss).
What is Phenylketonuria (PKU)?
Recessive disease, found mostly in people of European heritage. Not fatal. Inability to absorb/process a specific amino acid (meat, beans, dairy). Causes brain damage if people are exposed to this amino acid.
When did PKU screenings start at Canadian hospitals at birth?
1960s
What is Tay-Sachs disease?
Recessive disease, Found mostly in Jewish Populations-degenerative neurological disease and leads to death at or before age 4.
