Thursday, January 19th
Week 2 : Genetics and Intelligence
Nature vs. Nurture
Nature is only genes that we receive from our parents, essentially hereditary
Nurture is everything else, physical ad social environment
How do the above two interact to affect development of a child
Can`t study people without taking into their account their behaviour
Genotypes and Phenotypes
Genotypes – complete set of genes that are inherited, whereas Phenotypes – how those
traits are physically expressed in appearance and behaviour
Phenotypes affected by environment even before conception
Genes can be turned on and off
If genotypes were expressed the same in all cells, then all cells would be exactly the same
Has to be someway cells turn into brain cells, nerve cells, skin cells, etc
Genes turned on and off just to make different cells just to adapt to the environment that
one is on
Phenotypes affected by the environment even before conception
Eg. If rats don’t get their grooming in their early stages of life, they will become stressed for
the remainder of their lives, even if they do not have a high stress phenotype and their
stress phenotype becomes overly expressed than usual
Our parents upbringing and phenotype expression can affect ours in the end
Nucleus of every cell contains 23 pair of chromosomes, mitochondria and chloroplasts also
have chromosomal dna
Genes are sections of the chromosomes, and each gene is a segment of DNA which codes
for the production a particular protein
22 of these pairs are about the same and carry same gene sequences relevant to same traits
Except to sex chromosomes, whereas females have XX and males XY
Father determines the sex of the baby
Y chromosome activates other chromosomes to product testosterone and thus the
testes
As the X is so much bigger than Y, there are lots of stuff missing from Y, which explains
why males suffer from genetic mutations more than females
Genetic Mutations and Expression Thursday, January 19th
Mutations are caused by random errors and environmental factors such as carcinogens
When the egg and sperm are created during meiosis, there is a random crossover and
shuffling of the two pairs
When talking about hereditary, only genetic twins can be genetically identical
In our bodies, only about 10% of genes provide active instruction at any given time
Some genes are turned on for a few hours during development and then are turned off
never to be used again
Mendelian Genetics
Third of human genes have two forms called alleles
Homozygous vs heterozygous
Dominant vs recessive
Graph
Reaction ranges – worst to best outcome
Individuals are born with certain ranges, but have many possible outcomes
IQ vs environment graph
Restricted area – poor pre-natal care, born into poverty, poor education and nutrition,
possible parental abuse
Average area – nothing special during pre-natal care, child goes to school and parents go to
work, not much help on homework, doesn’t take child a lot of places
Enriched Area – vitamins, watches diet, exercises, very attentive to child, lots of extra
experiences, great education
Raj – typical like queen’s students?
Tony – possible illness such as ADHD, if given special education
More
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