Psyc 100 Notes

PSYC 100 – Week 14

Heredity and Genetics

* Darwin’s work – natural selection and exploration/experimental

* Genetics – the structure and function of genes – the study of the genetic makeup and how it influences their physical and behavioural characteristics

* How are genes transmitted from one generation to the next?

* Heredity – the sum of the traits and tendencies inherited from a person’s parents and other biological ancestors

* Darwin could not explain inheritance – he knew differences occurred within species and that those differences were subject to natural selection.., but did not know how adaptations were passed from parent to offspring or why offspring differences occurred

* The origin of Species was published by Gregor Mendel – did crossbreeding the pea plants and uncovered how height, colour and seed shape transmitted from one plant to next “inherited traits”

* Genetics provides proximal and explanations for psych

* How do they develop? Why do they behave the way they do? = genetics

* Differences are due to culture or ancestors

Basic Principles of Genetics

DNA

* determines heredity

* James Watson and Francis Crick discovered it

* Strands of sugar and phosphate that form the sides

* ATCG (adenine, thymine, guanine, cytosine)nucleotide molecules, are steps in ladder

* Sequence of nucleotides that form gene (can be short sequence or long)

* Sequence directs protein molecules to regulate biological and physical development

* The whole set of genetic material is known as genome (24 DNA molecules in girls, 25 in men)

* 30-40 thousand genes within genome (flies or worm have similar amount)

Genes are the Recipe

* Influence physical and behaviour development through protein synthesis

* Proteins are strings of amino acid that form a chain

* Proteins link with certain DNA sequences

* A sequence of three nucleotides corresponds to certain amino acid

* 3 may mean 1 amino acids but 2 A and 1 T...