Biopsychology Flashcards
A) What is evolutionary psychology?
B) What do they study?
A) Focuses on evolution of universal patterns of cognition and behaviour. Variations make individuals more/less successful in reproducing and passing on those genes.
B) Studies phenomena that may have evolved as adaptations: fear response, food preferences, mate selection, cooperative behaviours
A) What do behavioural geneticists study?
B) What do they often use to study?
A) Study how individual differences arrive (presently) through interaction of genes and environments
B) Often employ twin studies (compare rates given behavioural trait is shared among twins) and adoption studies (compare rates among biologically related relatives and adopted relatives)
What is genetic variation?
Genetic difference between individuals (is what contribute to species adaption of environment)
How many chromosome pairs are there?
23
Explain how chromosomes relate to chromatin relate to DNA relate to genes relate to alleles
Chromosomes are made of chromatin strands, which contain wrapped DNA, which contain genes, which contain alleles (variation of genes)
What is DNA?
genetic material, helix shaped molecule made of nucleotide base pairs
What are genes?
Sequences of DNA make up genes that partially control number of visible traits, single gene may have multiple alleles
A) What is a phenotype?
B) What is a genotype?
A) Observable physical characteristics of individual, combination of genetic and environment, can change over time
B) Genetic makeup of individual based on inherited DNA, actual genetic code
What does homozygous mean?
What does heterozygous mean?
Homozygous: two copies of the same allele (bb)
Heterozygous: combination of alleles for given gene (Bb)
Define polygenic
Controlled by more than one gene (eg. height, skin colour, weight)
-Few characteristics are controlled by single gene
What are gene mutations?
Sudden, permanent change in gene
Define range of reaction. Example given.
Asserts our genes set boundaries in which we can operate, environment interacts with genes to determine what degree they are expressed (some argue and say genes do not set a limit on potential)
Example: identical twins developing differently.
Define genetic-environmental correlation. Example given.
Genes influence our environment, and environment influences expression of our genes: genes and environment influence each other/
Example: child of NBA player exposed to basketball from early age, allowing child to realize full genetic, athletic potential. Parents’ genes which child shares influence child’s environment and that environment is suited to support child’s genetic potential
What do epigenetics study? Example given.
Environmental stressors and behaviours can “turn on” dominant genes, studies how same genotype can lead to different phenotypes
Example: pregnant person smoking changes their DNA (behavioural effects) and their unborn child’s DNA (environmental effects)
What are the two basic cell types?
Glial cells (glia) and neurons
6 facts about glia?
Outnumber neurons 10:1, play supportive role, help neurons line closely for communication, provide insulation, transport nutrients and waste products, mediate immune responses
What are neurons?
Interconnected information processors
What are 8 parts of a neuron?
Semipermeable membrane, nucleus, dendrites, terminal buttons, axon, myelin sheath, synapse, receptors
What are dendrites, terminal buttons and axon?
Dendrites: branching extensions off soma, input sites where signals are received from other neurons and sends it to cell body
Terminal buttons: transmit information to next neuron
Axon: range from fraction of inch to several feet, some have glial cells that form myelin sheath, transmits information across cell
What is a myelin sheath? What is consequence of more myelin and less myelin?
Myelin sheath coats axon, acts as insulator (increases speed signal travels), crucial for normal operation of neurons, the more neuron is used the more myelin develops
- More myelin, more effective communication within cell
- Multiple sclerosis, autoimmune disorder, involves large loss of myelin sheath in nervous system which prevents quick transmittal of information
What are neurotransmitters?
Signalling molecule sent from one neuron to another through synapses
What is a synapse?
Very small space between two neurons, site where communication between neurons occurs, points of contact between one neuron and another
What are receptors?
Proteins on cell surface where neurotransmitters attach with different shapes matching specific neurotransmitters
Fill in blank for how neurons communicate:
Signals received from ______ then transmitted electrically across the _____ and down extension from soma, called ______, which ends at multiple _____ ______, which contain ______ _______ that house neurotransmitters, synaptic vesicles release neurotransmitters into _____, neutrotransmitters travel across small space and bind with ______ on the dendrites of the other neuron
Signals received from DENDRITES then transmitted electrically across the SOMA and down extension from soma, called AXON, which ends at multiple TERMINAL BUTTONS, which contain SYNAPTIC VESICLES that house neurotransmitters, synaptic vesicles release neurotransmitters into SYNAPSE, neurotransmitters travel across small space and bind with receptors on the dendrites of other neuron
What is the purpose of the neuronal (semipermeable) membrane?
Neuron is surrounded by extracellular fluid and contains intercellular fluid (cytoplasm) and neuronal membrane keeps them separate. This is important because the electrical signal passing through the neuron requires the intra- and extracellular fluids to have membrane potential (difference in electrical charge) which provides energy for the signal
What is resting potential?
Between signals, neuron membrane’s potential is in state of readiness, ions line up on either side of membrane, ready to rush across when neuron goes active and membrane opens its gates
What allows movement of ions across neuronal membrane?
Action potential releases neurotransmitters which travels across and binds to gates which open them and allow Na+ to flow in (sodium-potassium pump)
What is action potential
Positive spike, electrical signal moves down axon like a wave, at each point some Na+ that enters cell diffuses to next section of axon, raising charge past threshold of excitation and triggering new influx of Na+ . Action potential moves all the way down to terminal buttons
What are 4 steps of Action potential
1) Resting state
2) Depolarization (passed the threshold of excitation_
-Reaches peak of action potential
3) Repolarization
-Hits hyperpolarization, the dip
4) Resting state
What is resting state?
More negative charge inside neuron than outside
1) Explain Threshold of Excitation
Neuron receives signal at dendrites by neurotransmitters, small pores/gates open, allowing Na+ to move in. the internal charge of cell becomes more positive and if charge reaches certain level (threshold of excitation) neuron becomes active and action potential begins
Explain transition from peak action potential to resting state
Additional pores open, causing influx of Na+ and huge spike in membrane potential (peak action potential). Positively charged K+ leaves and cell begins repolarization. It hyperpolarizes, becoming slightly more negative, then K+ returns and neuron levels off enters resting state