03. Important Information Flashcards
How similar are human and chimpanzee DNA molecules
98.8%
Discuss the relation of genes to behaviour
Genes never control behaviour directly, genes are associated with behaviour through their role in building and modifying the physical structures of the body. These structures interacting with the environment produce behaviour.
How do genes affect the body’s development
through their influence on the production of protein molecules
Genes are components of extremely long molecules of a substance called
DNA
Each protein molecule consists of a long chain of smaller molecules called
amino acids
How many amino acids might each protein molecule contain
several hundred to several thousand
How many distinct amino acids are there
20
How is RNA (ribonucleic acid) formed and what does it do?
Some portions of DNA serve as templates for producing RNA which in turn serves as a template for producing protein molecules
How many genes do human beings have?
About 20,000
Does most of the DNA in human cells code for proteins?
No
Chomosomes
Contain genetic material (DNA)
How many pairs of chromosomes does the normal human cell have
23 ( 1 of which contains the sex chromosomes)
What accounts for differences in among cells in the body
Different activation of genes
Describe meiosis
Each chromosome replicates itself once then the cell divides twice. Before the first division the chromosomes exchange genetic materially randomly resulting in genetically dissimilar cell which contain only HALF of the full number of chromosomes.
When do some pairs of genes blend their effects?
When the pair of alleles are neither dominant or recessive
Who is Gregor Mendel
Austrian monk who came up with the idea that units of heredity come in pairs and that one member of a pair can be dominant over the other
Why might a disease caused by two recessive genes (such as sickle cell) persist in the gene pool?
It may provide some secondary benefit (people with sickle cell are less likely to die of malaria)
Most of the behaviourally relevant traits in humans that derive from alteration at a single gene locus are…
Brain disorders
Categorical characteristics (genes)
Are characteristics that derive from variation at a single gene locus
Continual characteristics (genes)
Account for most anatomical and behavioural differences among individuals of any species and are measurable in degree
When and by whom was the first long term selective breeding study in psychology done?
1920s by Robert Tryon
DNA Methylation…
does not alter the protein that a gene will produce, but rather influences whether the genes will produce the protein at all. Most highly methylated genes do not produce their proteins; that is, they are “shut off”
histone modification
typically results in activating DNA
Research with nonhuman animals suggests that the way the human brain “learns” to react to stress through the production and processing of the hormone cortisol is likely governed by…
Epigenetic mechanisms
List 4 core concepts of Darwin’s theory of natural selection
- There is overproduction of offspring in each generation.
- There is variation in features or traits within members of a generation.
- Individual differences are inherited from one generation to the next.
- Individuals with collections of traits that fit well with the local environment are more apt to survive and have more offspring than individuals whose traits do not fit as well with the local environment.
he genetic variability on which natural selection acts has two main sources
(1) the reshuffling of genes that occurs in sexual reproduction
(2) mutations.
Biologists and psychologists who think in evolutionary terms find it useful to distinguish between two kinds of explanations of behaviour…
distal and proximate
Some inherited characteristics are inconsequential to survival or reproduction and result from the mutation of just one or two genes. Name one
different nose shapes according to race
Why do many psychologists avoid using terms such as instinct and innate?
- They imply “no experience necessary” (associated with genetic determinism). Genes don’t determine behaviour directly
- “instinct” is not an easily defined term
The eyebrow flash is…
According to Irenaus Eibl-Eibesfeldt a universal sign of greeting among friends (what a happy surprise to see you)
How do human emotional expression illustrate the point that species-typical behaviours can be modified by learning?
In general, people can identify each emotion more easily and accurately when it is expressed by other members of their own culture. There may also be differences is the application of some behaviours (e.g. only used with children/ strangers depending on the culture)