IB syllabus says:

1. Genetics & Behavior IB syllabus says: Key principle demonstrated: patterns of behavior can be inherited

2. What dominant traits have you inherited??? • Identify the following - Physical traits - Personality traits - Next to each state the parent from whom you inherited the trait.

3. Genetics Definition of Traits: Physical properties or behavior • This is the study of how living things pass on traits from one generation to the next • We are not clones of are parents, but some traits or characteristics appear generation after generation in predictable patterns • Scientists named these basic units of inheritance genes • Today – we know a lot about genes and how they work – Genes are carried by threadlike bodies called chromosomes, found in the nucleus of all cells • Humans have 23 pairs, peas have 7, monkeys have 27 • The main ingredient of chromosomes is DNA – a complex molecule in a double helix pattern • DNA carries the directions for a particular trait or a a group of traits • The human genome contains as many as many as 100,000 genes

4. Phenotype/genotype • Heredity – the biological mechanism for transmitting characteristics across generations. • Humans have about 80 000 each regulating different processes. • Code of inheritance (Spongebob!!)- two genes in a pair; gene pair splits – one parent contributes only one gene to the offspring then the other.. • Chromosomes ( humans have 23 pairs) regulate this splitting. • Genetic code carried by DNA is called genotype. • The dominant allele is always expressed. • Observed characteristics are called phenotype.

5. So…………..why study genes? • Our brain, CNS and endocrine system keep us aware of what is happening outside and inside our bodies • They enable use to think, use language and solve problems – so they guide our behavior • To understand why the brain, CNS and endocrine system function the way they do, we need to look at our genetic heritage, as individuals (behavior genetics)and as members of the human species (evolutionary psychology)

6. Nature/nurture…again?? • Environment impacts on outcomes. • In other words phenotype may be said to be based on genotype and environment. Tip………. • Think of examples where phenotype may be based on genotype and environment.

7. Human behavior genetics: Twin Studies • Twin studies are often used by psychologist to look at the influence of heredity and environment . • Identical (monozygotic - MZ) twins develop from a single fertilized ovum so any differences between them must be due to environmental factors (share 100 % similarity in genes) • Fraternal (dizygotic - DZ) twins develop from two separate fertilized eggs and are no more similar genetically than brothers and sisters. • A thought…if genes have any influence on the development of measured intelligence then MZs should show the greatest correspondence in test scores. Any difference would then have to be attributed to environmental or experiential influences.

8. Jim and Jim • One example of the amazing similarity of twins reared apart is the so-called “Jim twins”. These twins were adopted at the age of four weeks. Both of the adopting couples, unknown to each other, named their son James. Upon reunion of the twins when they were 39 years old, Jim and Jim have learned that: • Both twins are married to women named Betty and divorced from women named Linda. • One has named his first son James Alan while the other named his first son James Allan. • Both twins have an adopted brother whose name is Larry. • Both named their pet dog "Toy." • Both had some law-enforcement training and had been a part-time deputy sheriff in Ohio. • Each did poorly in spelling and well in math. • Each did carpentry, mechanical drawing, and block lettering. • Each vacation in Florida in the same three-block-long beach area. • Both twins began suffering from tension headaches at eighteen, gained ten pounds at the same time, and are six feet tall and 180 pounds.

9. Is intelligence inherited? Nature Vs. Nurture What do you think? Think about this – genetic inheritance is a constant therefore if intelligence is genetic then a person’s IQ should remian constant throughout their lives. ……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….......... Definition of Intelligence: The minds capacity to reason, to plan, to solve problems, to think abstractly, to comprehend ideas, to use language, and to learn.

10. Is intelligence inherited? Nature Vs. Nurture The pendulum swings between nature and nurture. If you asked 10 people 25 years ago – ‘is intelligence inborn or is it innate’ Most people would answer that it is a result of ‘upbringing’ (Nurture) But now most people would probably say ‘heredity’ i.e. – intelligence is inborn or innate (Nature) The shift in popular opinion parallels changes in scientific thinking This is an artificial debate – because both clearly play a role – neural plasticity shows this There is still disagreement regarding the relative influence of heredity (nature) and environment (nurture) on our thoughts, abilities, personalities and behaviors

11. Honzik (1948) reported high stability co-efficients- they were based on large numbers of people and obscure individual differences. • Mc Call et al (1973) reported far lower stability co-efficients. • He found that in140 middle-class children, the average IQ change between 2 ½ and 17 was 28 points!! • Most stable kids changed by 10 while 15% shifted 50 points or more….in either direction!!

12. Family correlations and IQ • Examine the table on page 2 of the reading provided. • With a partner explain what the table is showing. • Examine the third column labeled median correlation. • What conclusions can you draw regarding intelligence and genetic inheritance- consider environmental factors? • List three points of evidence, from the table, to support your conclusion.

13. Minnesota twin studies • Visual • Read Crane 54 and 55.

14. Problem with twin studies • Separated twins are often in fact in similar environmental settings- Shield (1962)- twins were raised in related branches of the parent’s families. • When you exclude such factors from the analysis correlations decrease from .77 to.51 • Twins have shared environment of mother’s womb. • When separated adoption agencies try and match families very closely. • Different IQ tests are used and then compared.

15. Solution to twins studies…. • Adoption studies – children share half their genes but none of their environment with their biological parents and some of their environment but no genes with adoptive parents. Munsinger (1975) ave. correlation bet adopted kids/ bio parents .48 +++ .19 between adop kids and adopt parents. So …….? • Using page three of reading and Crane 55 +56) outline the studies of - Scarr and Weinberg (1976) - Plomin and Petrill (1977) (Crane 56) - Rutter et al. (1998) ( p 4 of reading) - Heber et al (1968) • Clearly outline what conclusions can be drawn from these studies- both arguments and counter arguments.

16. Homework • Bullet point arguments presented in terms of the question (LO)- To what extent does genetic inheritance influence behavior? • Use p 6 of reading “how much does each contribute?” and p 7 “How do heredity and environment contribute?” Write a paragraph in response to the IB learning outcome.

17. Genetic explanation for eating disorders • Genetic science has not been able to identify genes for specific behaviors, such as those associated with eating disorders • So research examines whether eating disorders run in families • APA (1994) has shown that there is a much higher prevalence of those diagnosed with an eating disorder in a family than in the general population • However, this might be due to the environment that individuals grow up in – their behavior may be learnt from other family members • Twin studies also provide evidence research with MZ twins (who share identical genes) and DZ twins (that are no more genetically alike than other siblings). • Therefore – environmental factors can be eliminated to if there is a higher concordance rate of the disorder in MZ twins that DZ twins (concordance means that both twins have the same disorder).

18. Clinical characteristics of anorexia nervosa Background info

19. Clinical characteristics of bulimia nervosa Background info

22. The LAQ • The LAQ is the Long Answer Question, which you will be required to complete in the IB psychology exam • Paper 1 will have 3 SAQs (one on each of the LOAs) and one LAQ – you have 1 hour to complete the LAQ (the full paper is 2 hours). Make sure you review your psychology syllabus!

23. LAQ Command terms When you look at the syllabus, LAQ questions focus on assessment objective 3 (synthesis & evaluation) command terms which are (assessment objective 1 & 2 (knowledge & comprehension /application & analysis) command terms are used in SAQs, but can also appear in SAQ questions): • Compare (similarities) • Compare & contrast (similarities & differences) • Contrast (differences) • Discuss (considered & balanced view, with conclusion) • Evaluate (strengths and limitations) • Examine (look at the underlying assumptions of an argument or concept, uncover the interrelationships of the issue) • To what extent (consider the strengths & weaknesses of the argument, conclusion needed and supported by evidence and a sound argument)

24. LAQ - Things to remember… • Keep the intro v. brief, state how you will answer the question (unpacking), and give your THESIS Statement (Your main argument) • Never use ‘I’ • You can spend about 5 mins planning your answer • Make sure you take note of the command term – your answer must fit this • Refer to theories and studies (don’t worry if you don’t remember the name and date, just say ‘a study by…’) • Use PARAGRAPHS and leave a clear gap between each one • Your body paragraphs are really important, they must be well detailed, and make sure you connect what you are writing about to the question being asked • Remember to EVALUATE (MECG) – this is what this paper is all about • Look back at the question as you are writing, and make sure everything you write helps you to develop an argument in order to answer the question • Come to a conclusion at the end, it should not be too long, only a few sentences refer back to the main THESIS again

25. Possible LAQs You will answer an LAQ in class in one hour under exam conditions, and one of these questions will be given, and you will all have to answer it. • 1. With reference to research studies examine how environmental factors can affect physiological processes. • 2. Examine interactions between cognition and physiology in terms of behavior. • 3. Discuss the use of brain imaging technologies in investigating the relationship between biological factors and behavior.

26. LAQ planning • Make a plan, get it checked, and then share it with the group – it should be a plan and not longer than 1 page • Type up the plan an post it on the wiki • You will work on this on Thursday, present on Monday, and write the test on Tuesday

30. Possible LAQs You will answer an LAQ in class in one hour under exam conditions, and one of these questions will be given, and you will all have to answer it. • 1. With reference to research studies examine how environmental factors can affect physiological processes. • 2. Examine interactions between cognition and physiology in terms of behavior. • 3. Discuss the use of brain imaging technologies in investigating the relationship between biological factors and behavior.