Chapter 4: Genes, Evolution and Behaviour Flashcards
genotype
the specific genetic makeup of an individual
phenotype
the observable characteristics produced by that genetic endowment
chromosome
a structure of DNA in the nucleus that is formed when DNA is wrapped tightly around proteins
zygote
a cell containing 23 chromosomes from egg and 23 from sperm
gene
a segment of the DNA that codes for a protein that is used to express that trait on the organism
allele
two genes that are located on homologous chromosomes that code for a similar polypeptide that helps express that same type of trait
dominant
the particular characteristic that it controls will be displayed
recessive
characteristic that will not show up unless the partner gene inherited from the other parent is also recessive
epigenetics
refers to lasting changes in gene expression during development that were not due to genetic changes
recombinant DNA procedures
researches use specific enzymes to cut the long threadlike molecules of genetic DNA into pieces, combine them with DNA from another organism, and insert the new strands into a host organism, such as bacterium
knockout procedure
procedure done with animals that alters a specific gene in a way that prevents it from carrying out its normal function
heredity
the passage of characteristics from parents to offspring by way of genes
heritability
means how much of the variation in a characteristic within a population can be attributed to genetic differences
- applies to differences within a group, not to differences between groups
adoption study
research method in which a person who was adopted easily in life is compared on some characteristics both with the biological parents and adoptive parents
twin studies
one of the more powerful techniques used in behaviour genetics
- In conclusion, genetics and environmental factors almost always interact with each other to influence behaviour
reaction range
the range of possibilities that the genetic code allows
evolution
the change overtime in the frequency with which particular genes - and the characteristics they produce - occur within an interbreeding population
mutation
random events and accidents in gene reproduction during cell division
- mutations that occur in the cells that become sperm and egg cells will alter the genes, and those genes will be passed onto offspring
- help to create variation within a population’s physical characteristics which makes evolution possible
natural selection
- characteristics that increase the likelihood of survival and the ability to reproduce within a particular environment will be more likely to be preserved in the population and therefore will become more common in the species overtime
adaptations
allows organisms to meet recurring environmental challenges to their survival, thereby increasing their reproductive ability
parental investment
refers to the time, effort, energy and risk associated with caring successfully for each offspring
monogamous mating system
if both male and female investment is high
polyandry
one female mates with many males
molygynandry
in which all members of the group mate with all members of the group
- for highly social species, this is one possible way to reduce competition for a mate
cooperation
refers to situations in which one individual helps another and in so doing also gains some advantage
altruism
occurs when one individual helps another, but in doing so he or she accrues some cost
- There are two important theories of altruism:
1. kinselection theory - argues that altruism developed to increase the survival of relations
2. theory of reciprocal altruism - theory that argues altruism is long-term cooperation - that is, one individual may help another but that assistance will be reciprocated sometime in the future
