Hello everyone,
this is a summary including all lectures and necessary book chapters for the bachelor course biological psychology.
I hope it can be helpful for some of you.
Please keep in mind that this is merely a summary from my point of view and it is possible that I left out things that...
Summary Biological Psychology (Chandler book + lecture notes)
All for this textbook (10)
Written for
Tilburg University (UVT)
Psychology [EN]
Biological Psychology (400156B6)
All documents for this subject (7)
Seller
Follow
hannamalinger
Content preview
Psychobiology
Chapter 2: Genetics and Evolution
- Human Genome Project / Dolly the cloned sheep
o Focus on molecular structure of genes (DNA)
In the Beginning – Evolution
- Darwin → evolution; wrote about origin of species against pro-creationism
o Pro-creationism: god created all species
o Evidence-based approach by Darwin
- Natural selection (slow); ‘survival of the fittest’; selective breeding (quick)
- Evidence for the Theory of Evolution:
o Biogeography: environmental difference of temperature
o Fossil records
o Structural similarity: similar skeletal structures but serve diff. functions
o Embryology: similarities in utero; ontogeny recapitulation of phylogeny (ORP)
o Molecular Biology
- Darwanian good example for: environment changes biology and behavior
- Behavior: individual differences, interpretations, perceptions
The Evolution of Humans
- 600 mill. Years ago: complex water-dwelling organisms
- 150 mill. Years later: bone structures and nerves; vertebrae
- First incarnations of fish ventured onto land → amphibians develop
- Mammals → evolved from reptiles
From Evolution to Genetics
- Behavioral genetics → qualitative and quantitative traits
- Qualitative traits → influenced by single gene; follow simple pattern of inheritance
o Such as Mendelian inheritance
o Phenotypes are qualitatively different; presence/absence of disease
o Unaffected by environment
o Huntington’s disease
o Process not straightforward
o Mosaicism: not all cells genetically identical
§ Turner’s syndrome: deletion of X in some but not all cells
o Phenocopies → disorders caused by epigenetic influences (rubella virus
causing deafness even though DNA is fine)
- Quantitative traits → don’t follow simple patterns of inheritance
o Polygenetic disorders → multiple genes influence a disorder; less predictable
o ADHD → individuals expressing various degrees of symptom severity
o Phenotypic expression → subject to alternation and mitigation
(verminderung) by environmental factors
o Many psychological phenomena and psychological disorders are quantitative
o Quantitative trait loci (QTL) → multiple genes at different locations on the
chromosome contribute to a quantitative trait
1
,Mendelian Genetics
- Account differences in conspecifics → members of same species
o For inheritance, physiological and anatomical characteristics
- Dichotomous traits → characteristics that are in one form or another
o Pea seed either yellow or green → called trait (similar to eye color)
o Yellow seeded plant (Y1) + yellow seeded plant (Y2)= Y1:Y2
o True breeding lines and produce same trait in subsequent generations
- Dominant trait → here the Y1/Y2
- Recessive trait → here green seeds
o 1st generation Y1/Y2 expressed
o 2nd generation g1:g2 produced through carriers (Y1:g1)
- Phenotype → what is observed
- Genotype → what is genetically transmitted
Mendelian Inheritance: Huntington’s Disease
- Mutation in the HTT gene
- Codes protein huntingtin → involves DNA segment CAG
- Dominant allele
PKU: A Recessive Allele
- Phenylketonuria → form of delayed cognitive maturation
- Missing enzyme phenylalanine hydroxylase → needed to break down amino acid
phenylalanine
- Related substances build up and damage CNS → brain damage
- Symptoms: delayed mental and social skills, head size smaller, hyperactivity, jerking
movements of arms and legs
Chromosomes and Inheritance
- Autosome → first 22 chromosomes (excl. sex chromosomes)
- Karyotype → complete set of chromosomes
o 46 chromosomes; 22 identical pairs; 1 set ‘sex’ chromosomes
- Genome → whole of the genetic information of an organism
- Chromosome → long strand of DNA wound around histones
- Telomeres → genetic sequences at the end; protects DNA during cell division
- Cytogenetic bands → stripes on chromosomes (staining technique)
- Meiosis → cellular division
- Crossing over → during meiosis; different genetic information on chromatids
DNA – Deoxyribonucleic acid
- 1. Replicates itself to make new cells
- 2. Makes proteins and determines function of cell
- Proteins → make up 50% weight of dry cell
- Each chromosome = 2 strands of DNA
- DNA → carbon, sugar (ribose), nitrogenous base, phosphate group
- Nitrogenous bases → adenine, cytosine, guanine, thymine (p. 45)
o Adenine + thymine
2
, o Cytosine + guanine
Function of DNA
- Replication
- Protein synthesis
o Amino acids → codon (three nucleotids)
o Reading DNA → transcription
§ Creation of messenger ribonucleic acid (mRNA)
§ Carries code from nucleus to cytoplasm
§ mRNA not exact copy → uracil substitutes for thymine
§ three-nucleotide bases are specifying an amino acid
• if it goes wrong → sickle cell disease (e.g.); abnormal
heamoglobin → CAT (GUA) instead of CTT (GAA)
§ Exons → base sequences that code for proteins
§ Introns → noncoding sequences
§ Ribosomes are the translators
§ Transfer ribonucleic acid (tRNA) → take amino acid to ribosome
- Genetic Variation
o Polymorphism → differences in DNA among individuals
o Larger Polymorphism → single nucleotide polymorphisms (SNPs)
§ Each SNP represents a difference in a single nucleotide
§ No clear pattern of inheritance; only vulnerability not disorder itself
- Variable Number and Tandem Repeat
o Tandem repeat → repeated duplication of a core DNA sequence
§ Minisatellites → 2-4 base pairs
o Insertions (deletions) → loss/addition of 1 or more nucleotides; changes in
chromosome numbers
§ Deletions occur during meiosis; piece of chromosome breaks off; not
having full complement DNA
§ Results in neurodevelopmental disorder Williams-Beuren syndrome
• Deletion of chromosome 7
o Inversions → segments of chromosome turned round by 180°
§ Show no phenotypic abnormalities
o Translocations → balanced (equal parts of two chromosomes exchanged);
unbalanced (unequal proportions and leads to extra/missing genes)
o Monosomy → only one particular type of chromosome (Turner’s syndrome)
o Polyploid → more than two sets of chromosomes
- Biotechnology: polymerase chain reaction (PCR)
o Copies a known sequence of DNA; allows multiple copies to be made
o Electrophoresis → agarose gel block; DNA negatively charged; gel positively
charged
Epigenetics
- Functional modifications of the genome; no change in DNA
3
, Behavioral Genetics: Complex Interplay of Psychology and Genetics
- Nature-nurture debate
- Twin studies; familial studies
- Heritability → 1 (entirely attributable to genetics); 0 (caused by environmental
factors)
o Commonly → 0.5
o Schizophrenia → 0.75 genetic; 0.25 environmental
o Height → highly heritable 0.88
- Twin studies → close degree of genetic similarity between offspring, siblings, parents
- Turkheimer → 3 laws of behavioral genetics
o 1. All human behavioral traits are heritable
o 2. Effect of being raised in the same family is smaller than effect of genes
o 3. Variation in complex human behavioral traits not accounted for by the
effect of genes/families
- Adoption studies
- Virtual twins → share same rearing practices; estimate of environmental factors
DNA and Psychology
- Candidate genes → any gene thought likely to cause disease
Beyond Mendelian Inheritance: The Endophenotype
- Most disorders → complex polygenetic disorders
- Endophenotype → intermediate account of genes and environment
o Genes likely to cause disorder (e.g. ADHD) and the symptoms (e.g.
impulsivity) → theoretical account of the disorder (e.g. faulty behavioral
inhibition) that links physical (gene/brain) to the behavioral
o 1. Endophenotype associated with illness in population
o 2. Endophenotype is heritable
o 3. EPT is primarily state independent → manifest itself in an individual
whether or not they are symptomatic
o 4. Within families EPT and the disorder co-occur
o 5. EPT in affected family members found in non-affected family members at a
higher rate than in the general population
Human Genome Project
- 3.2 billion chemical nucleotide base pairs (A, C, T, G)
- 20,000-25,000 protein coding genes (80,000-140,000 estimated)
- 99.9% in all people is same sequence
- 2% of genome encodes instructions for synthesis of proteins
- 50% of sequences don’t code for proteins
- G, C gene-dense → A, T gene-poor
4
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller hannamalinger. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $7.00. You're not tied to anything after your purchase.
