Week 12 - Behavioural Genetics Flashcards
It is no longer a question of “Nature or Nurture”. Now we want to know:
What is the relative contribution of nature and nurture (of genes and environment)? What are the mechanisms by which they interact to affect biology and behaviour?
DNA is a polymer of four types of nucleotides, what are they?
adenine (A), guanine (G), thymine (T) and cytosine (C)
How do nucleotides form bonds?
A with T and C with G.
what is most important for DNA coding?
The order in which nucleotides are found along the strand (the sequence).
How do mutations occur?
When a cell divides, the DNA helix is “unzipped” so that a new complementary strand can be made. Sometimes errors are made when the new strand is made so that the new strand is not exactly the same. Most of the time, a repair enzyme can fix this error, but sometimes the error is not caught which results in mutation.
The process of creating RNA from DNA is called what?
Transcription.
What is RNA?
a single strand chemical that can serve as a template for the synthesis of proteins.
It has the same bases, except thymine, instead, it has a nucleotide called uracil.
By the process of translation what happens?
the protein-building information in an mRNA is decoded (translated) into a sequence of amino acids.
What is a codon?
“the genetic words”, carries protein building information, is three bases long (e.g. A-C-G).
What is a base-pair substitution?
A mutation in which one nucleotide and its partner are replaced by a different pair.
What is an allele?
A variant of a gene.
Being homozygous for a gene means that…
a person has an identical pair of genes (or alleles) on the two chromosomes.
Being heterozygous for a gene means that…
a person has an unmatched pair of genes (or alleles) on the two chromosomes.
What do period genes do?
produce proteins called PER
What do timeless genes do?
produce proteins called TIM
