Lecture 6 Flashcards
How many chromosomes do we have? how many pairs do we have?
46 chromosomes
23 pairs
What makes up a chromosome?
chromatin coils around histones which form the DNA double helix that condenses to make up chromosomes.
What contain all your genetic information?
Chromosomes
What are genes?
Sections of DNA that control your physical characteristics
In what way are genes like a recipe?
It’s like baking a cake. You can take the same base recipe and change it to make different flavours
What are alleles?
A variation of a gene (Ex: a gene for eye colour could have alleles for blue, brown or green)
If we get one allele for eye colour from one parent and one allele from the other parent. What determines your eye colour?
The relationship between the alleles. In a dominant/ recessive relationship, If a person carries both alleles, the dominant allele will show, not the recessive allele.
What is an example of a Dominant trait?
What is an example of a recessive trait?
How do you show this relationship when writing?
A dominant trait is shown by an upper case letter (Ex:
B = brown eyes)
A recessive trait is shown by a lower case letter (Ex: b = Blue eyes)
What do we use to determine the frequency of certain characteristics in children using parental genotypes?
Punnett squares
What is the difference between a genotype and a phenotype?
A genotype is the genetic code for a trait (Ex: BB or Bb or bb) (inherited)
The phenotype is the way that trait presents (Ex: blue eyes or brown eyes) (interaction of gene and environment, can be changed)
What 2 factors can affect phenotype?
Gene disorders and interactions with your environment
Can identical twins look different? Why or why not?
Twins can start off looking identical but different lives and stresses can cause physical differences based on environment they’ve been in (Ex: smoker vs non-smoker)
What is range of reaction theory?
our genes set limits on a given characteristic, our environment determines to which degree they are expressed (Ex: genetic potential for high IQ may not be fostered as a result of uneducated parents and socio-economic status therefore limiting IQ in developmental stages)
What is gene environment correlation?
As we show genetic propensity for something, we are more likely to continue to gravitate towards those environments. Our environment then determines to which degree our genes are expressed. (Ex: is good at soccer at young age, is pushed into soccer rather than dance. Gets better at soccer, never put in a position to be good at dance).
In a healthy environment, is someone with a genetic predisposition for schizophrenia more likely to develop it?
no. Someone with a predisposition to schizophrenia is much more likely to develop it in a stressful environment though.
