Edexcel A Level Biological Psychology EXAM QUESTIOS AND
CORRECT ANSWERS || LATEST UPDATE
Monozygotic twins -CORRECT ANSWER: Identical, share 100% of their genes as they come
from one fertilised egg.
What should be considered about MZ twins? -CORRECT ANSWER: - Do not share the same
environment
- There are some physical differences, such as fingerprints
- Can become less identical over time
- Some characteristics, such as IQ and personality might become more alike as twins age
Epigenetic modification -CORRECT ANSWER: Different environmental influences affect
which genes are switched on and off. Younger MZ twins have few epigenetic differences.
Dizygotic twins -CORRECT ANSWER: Not identical, come from two separate eggs fertilised at
the same time. Share 50% of genes.
Why are twin studies useful? -CORRECT ANSWER: If a characteristic comes from genes, MZ
twins should be more likely to share it. Psychologists can compare behaviour between a group of
identical twins and fraternal twins to see which group shared the most similarity.
Concorance rate -CORRECT ANSWER: The extent to which the same behaviour is the same
between twins. An agreement rate when both twins have got a characteristic.
Strengths of using twin studies -CORRECT ANSWER: - Twin studies are the main way of
finding out if genes have any influence on behaviour.
- Both twins share their environment, so there should not be many environmental differences
between the twins.
,Weaknesses of using twin studies -CORRECT ANSWER: - MZ twins will be treated more like
twins than DZ twins, so environments are not the same.
- Epigenetic modification, there are differences between twins. Difficult to say if a characteristic
is caused by genes conclusively
Gottesman and Shields (1966) procedure -CORRECT ANSWER: - 16 year period (longitudinal)
using 5 twin studies
- To see if there was a relationship between genetic make up and development of schizophrenia
by looking at concordance rate
- 57 twin pairs (24 MZ and 33 DZ)
- Hospital notes and semi-structured interviews
Gottesman and Shields (1966) results -CORRECT ANSWER: - MZ twins - 42%
- DZ twin - 17%
Gottesman and Shields (1966) conclusion -CORRECT ANSWER: Genes do play a role in the
development of schizophrenia, but can't conclusively say it is solely due to genes.
Why are adoption studies useful? -CORRECT ANSWER: It is the only direct way to isolate the
influence of genes and the environment.
In what circumstances in adoption studies suggest the roles of genes? -CORRECT ANSWER:
Similarities between child and their biological parents
In what circumstances in adoption studies suggest the roles of environment? -CORRECT
ANSWER: Similarities between child and their adoptive parents
Kety et al (1994) -CORRECT ANSWER: - Research in Finland
- Sample of 155
, - 9 adopted children, 8 had biological mothers with schizophrenia or a form of psychoses
Strengths of adoption studies -CORRECT ANSWER: - Developmental trends (patterns) can be
studied because studies are longitudinal. Same children can be studied at different times during
development.
- Control for environment, separates genes from environment.
Weakness of adoption studies -CORRECT ANSWER: - Adopted children are often placed into
families very similar to their biological families
- They are matched, so the environments might not be as different as thought
What are the 3 main brain scanning techniques? -CORRECT ANSWER: PET scans, CAT scans
and fMRI scans
How do PET scans work? -CORRECT ANSWER: - inject patient with FDG (radioactive)
- task is given to stimulate the brain
- glucose is used up, radioactive atoms break down, gamma rays produced
- high activity (red)
- low activity (blue)
What are PET scans useful for? -CORRECT ANSWER: Investigating areas of the brain that are
not functioning normally, indicate damage or tumours.
Strengths of PET scans -CORRECT ANSWER: - Reasonably non-invasive, less dangerous than
surgery
- Valid measure
- Reliable because it can be repeated and same results found again
Weaknesses of PET scans -CORRECT ANSWER: - Invasive
CORRECT ANSWERS || LATEST UPDATE
Monozygotic twins -CORRECT ANSWER: Identical, share 100% of their genes as they come
from one fertilised egg.
What should be considered about MZ twins? -CORRECT ANSWER: - Do not share the same
environment
- There are some physical differences, such as fingerprints
- Can become less identical over time
- Some characteristics, such as IQ and personality might become more alike as twins age
Epigenetic modification -CORRECT ANSWER: Different environmental influences affect
which genes are switched on and off. Younger MZ twins have few epigenetic differences.
Dizygotic twins -CORRECT ANSWER: Not identical, come from two separate eggs fertilised at
the same time. Share 50% of genes.
Why are twin studies useful? -CORRECT ANSWER: If a characteristic comes from genes, MZ
twins should be more likely to share it. Psychologists can compare behaviour between a group of
identical twins and fraternal twins to see which group shared the most similarity.
Concorance rate -CORRECT ANSWER: The extent to which the same behaviour is the same
between twins. An agreement rate when both twins have got a characteristic.
Strengths of using twin studies -CORRECT ANSWER: - Twin studies are the main way of
finding out if genes have any influence on behaviour.
- Both twins share their environment, so there should not be many environmental differences
between the twins.
,Weaknesses of using twin studies -CORRECT ANSWER: - MZ twins will be treated more like
twins than DZ twins, so environments are not the same.
- Epigenetic modification, there are differences between twins. Difficult to say if a characteristic
is caused by genes conclusively
Gottesman and Shields (1966) procedure -CORRECT ANSWER: - 16 year period (longitudinal)
using 5 twin studies
- To see if there was a relationship between genetic make up and development of schizophrenia
by looking at concordance rate
- 57 twin pairs (24 MZ and 33 DZ)
- Hospital notes and semi-structured interviews
Gottesman and Shields (1966) results -CORRECT ANSWER: - MZ twins - 42%
- DZ twin - 17%
Gottesman and Shields (1966) conclusion -CORRECT ANSWER: Genes do play a role in the
development of schizophrenia, but can't conclusively say it is solely due to genes.
Why are adoption studies useful? -CORRECT ANSWER: It is the only direct way to isolate the
influence of genes and the environment.
In what circumstances in adoption studies suggest the roles of genes? -CORRECT ANSWER:
Similarities between child and their biological parents
In what circumstances in adoption studies suggest the roles of environment? -CORRECT
ANSWER: Similarities between child and their adoptive parents
Kety et al (1994) -CORRECT ANSWER: - Research in Finland
- Sample of 155
, - 9 adopted children, 8 had biological mothers with schizophrenia or a form of psychoses
Strengths of adoption studies -CORRECT ANSWER: - Developmental trends (patterns) can be
studied because studies are longitudinal. Same children can be studied at different times during
development.
- Control for environment, separates genes from environment.
Weakness of adoption studies -CORRECT ANSWER: - Adopted children are often placed into
families very similar to their biological families
- They are matched, so the environments might not be as different as thought
What are the 3 main brain scanning techniques? -CORRECT ANSWER: PET scans, CAT scans
and fMRI scans
How do PET scans work? -CORRECT ANSWER: - inject patient with FDG (radioactive)
- task is given to stimulate the brain
- glucose is used up, radioactive atoms break down, gamma rays produced
- high activity (red)
- low activity (blue)
What are PET scans useful for? -CORRECT ANSWER: Investigating areas of the brain that are
not functioning normally, indicate damage or tumours.
Strengths of PET scans -CORRECT ANSWER: - Reasonably non-invasive, less dangerous than
surgery
- Valid measure
- Reliable because it can be repeated and same results found again
Weaknesses of PET scans -CORRECT ANSWER: - Invasive
