Genetic Influences Flashcards
When are genotypes present and when are phenotypes?
Genotypes are present from contraception and can never change, however phenotypes are subject to change and can be affected by other genes and the environment
Define genotype and phenotype?
- Genotype is the genetic makeup of an individual
- phenotype is the observable characteristics produced by the genotype
What are chromosomes and what is it compose of?
Chromosomes are material of heredity. DNA in the chromosomes provide genes which is our hereditary blue print
How many chromosomes does every cell in our body have besides sex cells? How many do sex cells have?
Every cell besides sex cells has 46 chromosomes. Sex cells have 23
How does genetic transmission pass on from parent to offspring?
A zygote is formed after conception which is the joining of 23 chromosomes from an egg cell (the mom) and 23 chromosomes from a sperm cell (the dad), which gives the zygote (the offspring) 46 chromosomes
What are alleles?
alleles are alternative forms of a gene that produce different characteristics
Why are genotypes and phenotypes not identical ?
because one can be dominant and show up and one can be recessive and not show up. So dominant genes are part of your genotype and also part of your phenotype, but recessive genes would only be a part of your genotype only
What is the difference between dominant and recessive genes?
- dominant genes show up in your genotype and phenotype
- recessive genes will not show up unless both parents also have the recessive gene
What is polygenic transmission?
when gene pairs produce a phenotypic appearance not based on dominant or recessive, but based on the combination of the two genes from the parents put together. For example, height is a polygenic transmitted trait
What are recombinant DNA procedures?
recombinant DNA procedures are when researchers use specific enzymes to cut the genetic DNA of one organism into pieces, then combine it with DNA in another organism and insert new strands into a host organism such as bacteria. Inside the host, the new DNA combination continues to divide and produce many copies of itself
What is a knockout procedure and what is it used for?
A knockout procedure is when a gene is altered in a way that it prevents it from carrying out its normal function. Researchers do this to disrupt the behaviour of a gene in order to help identify the genes involved in the behaviour
What is one advantage and one disadvantage of knockout procedure?
- Advantage: good at identifying genes
- Disadvantage: risky because if you distrupt one gene or behaviour then it can lead to huge implications
What is a good alternative to knockout procedures? Why is it not used today?
Genetic engineering is a good alternative to knockout procedures, because if we create clones, we can better preform operations on them and find out information about us from them. However, its not used today because its not ethical
What is heritability coefficient? What does it depend on?
Heritability coefficient is the statistically estimated extent to which variation in a particular characteristic within a group can be attributed to genetic factors.
- Depends on groups and changes between groups due to environment and resources
What is heredity?
Heredity is the passage of characteristics from parent to offspring through genes
What does it mean if a characteristic has high concordance in people who are more related to each other?
It points to possible genetic contribution (the genes are the reason why theres high concordance in the trait between two individuals who are related)
What is an adoption study and why is it done?
An adoption study is when researchers compare the characteristics of an adopted child with their biological parents and their adoptive parents to see what traits are environmental and what are hereditary
What are twin studies? what do they shown to achieve in terms of heritability estimates?
Twin studies is studying the behaviour of separated identical twins who are raised in different environments after birth and seeing differences and similarities between their behaviours. Genetic and environmental factors always interact with each other to influence behaviour. If these twins have high similarities in certain behaviours, it could mean that they are hereditary
What is a reaction range? provide an example.
reaction range is the range of possibilities (upper and lower limits) of a genetically influenced trait that the genetic code allows.
- For example … I.Q is a genetically influenced trait and its reaction range depends on the genetics of the person and also the environment.
In what ways is the reaction range for intelligence (IQ) affected by the environment?
Enriched environments are expected to allow a person’s intelligence to develop in the upper region of his/her reaction range, whereas the deprived environments may limit intelligence to the lower position on the range
What is the Five Factor Model and what are the 5 factors in it?
Its the idea that personality and behaviour could be traced to differences in brain development or function, and therefore have some sort of genetic component to them. The Five Factor Model is a theory on personality traits and 5 broad personality dimensions of traits that can be linked to genetics called “The Big 5”
- Extraversion-Introversion
- Agreeableness
- Conscientiousness
- Neuroticism
- Openness to experience
What are the 3 parts of total variation that arises from seperating identical twins at birth?
- variation due to environment
- variation due to genetic factors
- variation due to other factors such as unique, individual experiences
