Biological Psychology (LO)

Question 1

Differentiate between chromosomes, DNA, and genes

Answer 1

• Chromosomes: Thread-like structures in the cell nucleus made of DNA and proteins. Humans have 23 pairs of chromosomes.
• DNA (Deoxyribonucleic Acid): The molecule that carries genetic information. It consists of two long chains of nucleotides twisted into a double helix.
• Genes: Segments of DNA that code for specific traits or proteins. They are the functional units of heredity.

Question 2

Differentiate between phenotypes and genotypes

Answer 2

• Genotype: The genetic makeup of an organism, including all of its genes (e.g., AA, Aa, or aa for a specific gene).
• Phenotype: The observable physical or behavioral characteristics of an organism (e.g., eye color, height) that result from the interaction of its genotype with the environment.

Question 3

Identify and differentiate between homozygous and heterozygous genes

Answer 3

• Homozygous: When an individual has two identical alleles for a gene (e.g., AA or aa).
• Heterozygous: When an individual has two different alleles for a gene (e.g., Aa).

Question 4

Identify and differentiate between dominant and recessive genes

Answer 4

• Dominant Gene: An allele that will express its trait even if only one copy is present (e.g., Aa or AA will result in the dominant trait being expressed).
• Recessive Gene: An allele that only expresses its trait if two copies are present (e.g., aa will result in the recessive trait being expressed).

Question 5

Apply descriptions of genes to examples

Answer 5

Example: For a gene controlling eye color, if brown is dominant (B) and blue is recessive (b), a person with a genotype of Bb or BB will have brown eyes, while someone with bb will have blue eyes.

Question 6

Identify and differentiate between monozygotic and dizygotic twins

Answer 6

• Monozygotic (Identical) Twins: Twins that develop from a single fertilized egg that splits into two. They share 100% of their genes.
• Dizygotic (Fraternal) Twins: Twins that develop from two separate eggs fertilized by two different sperm. They share about 50% of their genes, like regular siblings.

Question 7

Identify how behavioural genetics is used to study nature vs nurture relationships

Answer 7

Behavioural Genetics uses twin studies, family studies, and adoption studies to investigate the relative contributions of genetics (nature) and environment (nurture) on behavior. By comparing similarities between identical and fraternal twins, researchers can estimate the heritability of traits.

Question 8

Apply behavioural genetics principles to determine the contributions of nature vs nurture

Answer 8

If identical twins (who share 100% of their genes) show more similarity in intelligence than fraternal twins (who share 50% of their genes), the higher similarity suggests a greater genetic influence (nature). However, differences between identical twins can indicate environmental effects (nurture).

Question 9

Apply the correct use of heritability values

Answer 9

Heritability is a statistical measure that estimates the proportion of the total variance in a trait that is due to genetic differences within a population. For example, if heritability for intelligence is 0.60, it means that 60% of the variation in intelligence within the population is attributed to genetic factors.

Question 10

Differentiate between the approaches of behavioural genetics and behavioural genomics

Answer 10

• Behavioural Genetics: Focuses on studying how variation in behavior is related to genetic differences by analyzing specific traits in families, twins, and populations.
• Behavioural Genomics: Investigates how individual genes and interactions between genes influence behavior. It looks at the molecular mechanisms underlying behavior.

Question 11

Identify correct and problematic characterizations of genetic research

Answer 11

• Correct Characterization: Genetic research explores the complex interactions between genes and environment, recognizing that most traits are influenced by multiple genes and environmental factors.
• Problematic Characterization: Oversimplifications, such as claiming that a single gene is solely responsible for complex traits (e.g., intelligence or aggression), can be misleading. Many traits are polygenic and influenced by environmental factors.

Question 12

Identify when certain gene variations contribute to depression

Answer 12

Some genetic variations (e.g., in the serotonin transporter gene, 5-HTTLPR) may increase vulnerability to depression, especially when combined with stressful life events. This gene-environment interaction suggests that genetics and environmental stressors together contribute to the development of depression.

Question 13

Apply the most appropriate description of gene-environment interactions

Answer 13

Gene-Environment Interaction: The way genes and the environment influence each other. For example, an individual with a genetic predisposition to high stress sensitivity may only develop anxiety if they experience significant environmental stress (e.g., childhood trauma).

Question 14

Apply evolutionary principles to predict which traits will become more common over generations

Answer 14

Natural Selection: Traits that improve survival and reproduction are more likely to be passed on to future generations. For example, in a population where resource scarcity favors individuals who can store fat efficiently, the trait for fat storage may become more common over time.

Question 15

Differentiate the evolutionary pressures of males and females in the context of mate selection

Answer 15

• Males: Evolutionary pressures may favor traits like seeking multiple partners to maximize reproductive success, focusing on youth and fertility in mates.
• Females: Evolutionary pressures may favor selecting mates who can provide resources and protection for offspring, prioritizing traits like stability and status.

Question 16

Identify accurate summaries of the research on sex differences in cognition

Answer 16

• Research has shown some differences in specific cognitive abilities between males and females:
  
  • Females tend to excel in verbal tasks, reading comprehension, and language-related skills.
  • Males tend to perform better in spatial tasks, such as mental rotation and navigation.
• However, these differences are small, and there is more variability within each gender than between genders. Societal and cultural factors also play a role in these differences.

Question 17

Identify and differentiate the discussed structures of the neuron

Answer 17

• Dendrites: Branch-like structures that receive signals from other neurons.
• Cell Body (Soma): Contains the nucleus and is responsible for maintaining the neuron’s health.
• Axon: A long projection that transmits electrical signals away from the cell body.
• Myelin Sheath: A fatty covering around the axon that increases the speed of electrical signals.
• Axon Terminals (Terminal Buttons): Endings of the axon where neurotransmitters are released.
• Synapse: The gap between neurons where neurotransmitters pass the signal to the next neuron.

Question 18

Differentiate between sensory, motor, and interneurons

Answer 18

• Sensory Neurons: Carry information from sensory organs (e.g., eyes, skin) to the central nervous system (CNS).
• Motor Neurons: Transmit signals from the CNS to muscles and glands to trigger movement or responses.
• Interneurons: Found within the CNS, they connect sensory and motor neurons and process information.

Question 19

Identify and differentiate ways in which the brain achieves neural plasticity

Answer 19

• Synaptogenesis: Formation of new synaptic connections between neurons.
• Neurogenesis: The creation of new neurons, particularly in regions like the hippocampus.
• Synaptic Pruning: The removal of weaker or less-used synaptic connections to strengthen more efficient ones.
• Rewiring: Neurons reorganizing their pathways in response to learning or injury.

Question 20

Apply the most appropriate description of how the brain changes with experience

Answer 20

• Experience-Dependent Plasticity: The brain’s ability to change and adapt based on individual learning and experiences, such as learning a new skill or recovering from brain injury.
• Example: London taxi drivers have larger hippocampi due to navigating complex street maps, illustrating experience-dependent plasticity.

Question 21

Generalize and identify cases of neural plasticity in human behaviour

Answer 21

• Skill Acquisition: Learning new motor skills (e.g., playing an instrument) leads to changes in brain areas related to movement.
• Recovery After Stroke: The brain reorganizes itself to compensate for lost functions, often with therapy, showing plasticity in response to injury.

Question 22

Identify how different glial cells contribute to brain functions

Answer 22

• Astrocytes: Maintain the blood-brain barrier, provide nutrients, and repair brain tissue.
• Oligodendrocytes: Produce myelin in the central nervous system, which insulates axons and enhances signal transmission.
• Microglia: Act as immune cells in the brain, cleaning up debris and protecting neurons from damage.
• Schwann Cells: Produce myelin in the peripheral nervous system, similar to oligodendrocytes in the CNS.

Question 23

Identify how glial cells contribute to conditions like multiple sclerosis

Answer 23

In Multiple Sclerosis (MS), the immune system mistakenly attacks oligodendrocytes, which produce myelin in the CNS. This damages the myelin sheath, leading to impaired electrical signaling, muscle weakness, and cognitive decline.

Question 24

Identify how the ions present in neurons contribute to electrical signalling

Answer 24

• Sodium (Na⁺) and potassium (K⁺) ions are crucial for creating electrical signals. The movement of these ions across the neuron’s membrane generates action potentials, allowing neurons to transmit information.
• Calcium (Ca²⁺) ions play a role in the release of neurotransmitters at the synapse.

Question 25

Differentiate the forces that contribute to ion movement within the cell

Answer 25

• Diffusion: Ions move from areas of high concentration to low concentration.
• Electrostatic Pressure: Ions move toward areas of opposite electrical charge (positive ions move toward negative areas and vice versa).
• Active Transport (e.g., Sodium-Potassium Pump): This pump actively moves Na⁺ out and K⁺ into the cell, maintaining the resting potential.

Question 26

Identify and differentiate between the resting potential, action potential and refractory periods of neuron signalling

Answer 26

• Resting Potential: The stable negative charge inside a neuron when it is not firing (~ -70mV).
• Action Potential: A rapid change in voltage (from negative to positive and back to negative) that travels down the axon when the neuron fires (~ +40mV).
• Refractory Period: A brief period after an action potential during which the neuron cannot fire again, ensuring signals only travel in one direction.

Question 27

Differentiate between polarization, hyperpolarization, and depolarization

Answer 27

• Polarization: The neuron’s resting state, where the inside of the cell is more negatively charged than the outside.
• Depolarization: When Na⁺ enters the cell, reducing the negative charge, and triggering an action potential if the threshold is reached.
• Hyperpolarization: When the cell becomes more negatively charged than the resting potential, making it harder for the neuron to fire again immediately.

Question 28

Identify the conditions under which a neuron will fire

Answer 28

A neuron will fire (generate an action potential) when depolarization reaches the threshold potential (~ -55mV). This usually occurs when enough excitatory neurotransmitters bind to receptors on the neuron, allowing Na⁺ to enter and reduce the negative charge inside the neuron.

Question 29

Identify the most accurate description of how neurons communicate with one another

Answer 29

Neurons communicate via synapses. When an action potential reaches the axon terminals, it triggers the release of neurotransmitters into the synaptic cleft. These neurotransmitters bind to receptors on the dendrites of the next neuron, influencing whether that neuron will fire an action potential.

Question 30

Identify how reuptake contributes to ongoing signalling between neurons

Answer 30

Reuptake is the process by which neurotransmitters are reabsorbed by the presynaptic neuron after being released into the synapse. This process helps regulate the level of neurotransmitters in the synapse and ensures that their effects are not prolonged excessively, maintaining balance and allowing new signals to be transmitted.

Question 31

Identify and differentiate the major functions associated with the neurotransmitters discussed

Answer 31

1. Dopamine: Involved in reward, motivation, and motor control.
2. Serotonin: Affects mood, sleep, and appetite.
3. Acetylcholine: Important for muscle contraction and memory.
4. GABA: The major inhibitory neurotransmitter, reduces neural activity.
5. Glutamate: The major excitatory neurotransmitter, important for learning and memory.
6. Norepinephrine: Involved in arousal and stress response.

Question 32

Differentiate between excitatory and inhibitory neurotransmitters

Answer 32

• Excitatory Neurotransmitters (e.g., glutamate) increase the likelihood that the receiving neuron will fire an action potential by causing depolarization.
• Inhibitory Neurotransmitters (e.g., GABA) decrease the likelihood of firing by causing hyperpolarization, making it harder for an action potential to occur.

Question 33

Apply the terms of direct and indirect agonist/antagonist based on descriptions of a drug’s action and effects

Answer 33

• Direct Agonist: Binds directly to receptors and mimics the action of a neurotransmitter (e.g., nicotine binds to acetylcholine receptors).
• Indirect Agonist: Increases the effect of a neurotransmitter without binding directly (e.g., SSRIs increase serotonin by preventing reuptake).
• Direct Antagonist: Binds to receptors and blocks the action of a neurotransmitter (e.g., naloxone blocks opioid receptors).
• Indirect Antagonist: Decreases the action of a neurotransmitter without binding to receptors (e.g., drugs that block neurotransmitter synthesis).

Question 34

Identify and differentiate the divisions of the nervous system

Answer 34

• Central Nervous System (CNS): Composed of the brain and spinal cord.
• Peripheral Nervous System (PNS): Connects the CNS to the rest of the body and has two main divisions:
  
  • Somatic Nervous System: Controls voluntary movements (skeletal muscles).
  • Autonomic Nervous System: Controls involuntary functions (heart rate, digestion) and has two divisions:
    
    • Sympathetic Nervous System: Prepares the body for stress (‘fight or flight’).
    • Parasympathetic Nervous System: Promotes rest and energy conservation (‘rest and digest’).

Question 35

Identify the relevant division of the nervous system based on a description of human behaviour

Answer 35

• Sympathetic Nervous System: Activated when a person is stressed or frightened, increasing heart rate and blood flow.
• Parasympathetic Nervous System: Activated during relaxation, decreasing heart rate and promoting digestion.
• Somatic Nervous System: Used during voluntary actions like moving your arm to pick up an object.

Question 36

Identify and differentiate the structures of the hindbrain and midbrain based on their associated functions and how they affect human behaviour

Answer 36

• Hindbrain:
  
  • Medulla: Controls vital functions like heart rate and breathing.
  • Pons: Involved in sleep, respiration, and arousal.
  • Cerebellum: Important for motor coordination and balance.
• Midbrain:
  
  • Superior Colliculus: Involved in visual processing and eye movements.
  • Inferior Colliculus: Processes auditory information.

Question 37

Apply learning of functions of hindbrain and midbrain regions to determine and describe which structure has been damaged in hypothetical patients

Answer 37

• Damage to the medulla could result in problems with breathing or heart rate regulation.
• Damage to the cerebellum might cause coordination issues, leading to balance problems or motor dysfunction.
• Damage to the inferior colliculus could affect the ability to process auditory information, leading to hearing difficulties.

Question 38

Identify and differentiate the structures of the forebrain based on their associated functions and how they affect human behaviour

Answer 38

• Thalamus: Relay station for sensory information.
• Hypothalamus: Regulates basic drives such as hunger, thirst, and body temperature.
• Amygdala: Involved in emotion, especially fear and aggression.
• Hippocampus: Important for memory formation.
• Basal Ganglia: Involved in motor control and procedural learning.
• Cerebral Cortex: Higher-order functions such as decision-making, perception, and complex thought.

Question 39

Apply learning of functions of forebrain regions to determine and describe which structure has been damaged in hypothetical patients

Answer 39

• Damage to the hippocampus could lead to memory issues, such as difficulty forming new memories (e.g., amnesia).
• Damage to the amygdala may result in a lack of fear response or difficulties processing emotions.
• Damage to the cerebral cortex could impair complex thinking, perception, or voluntary movement, depending on which lobe is affected (e.g., frontal lobe damage might impair decision-making and motor functions).

Question 40

Identify and differentiate the cells and regions of the cortex based on their associated functions and how they affect human behaviour

Answer 40

• Cerebral Cortex: The outer layer of the brain, involved in high-level functions.
  
  • Frontal Lobe: Associated with reasoning, planning, movement, and problem-solving
  • Parietal Lobe: Processes sensory information, such as touch, temperature, and pain.
  • Temporal Lobe: Involved in auditory processing and memory.
  • Occipital Lobe: Responsible for visual processing.
• Cells:
  
  • Pyramidal Cells: Principal neurons in the cerebral cortex involved in communication between cortical areas
  • Interneurons: Local circuit neurons that modulate the activity of pyramidal cells and play a role in processing information.
• Effects on Human Behavior: Damage to specific regions can lead to deficits in behavior, such as difficulty in problem-solving (frontal lobe) or impaired sensory perception (parietal lobe).

Question 41

Differentiate localization and circuit based views of brain function

Answer 41

• Localization View: Suggests specific functions are mapped to specific areas of the brain (e.g., Broca’s area for speech production).
• Circuit-Based View: Emphasizes that functions arise from networks of interconnected regions rather than isolated areas, acknowledging the brain’s plasticity and connectivity.

Question 42

Identify and apply the most appropriate summary of how the brain operates

Answer 42

The brain operates through a complex network of neurons and synapses, where different regions work together to process information, control behavior, and adapt to experiences. It integrates sensory input, regulates bodily functions, and facilitates cognitive processes and emotions.

Question 43

Identify accurate descriptions of how evolution has shaped brain structure

Answer 43

Evolution has led to increased brain size relative to body size, particularly in mammals and primates. Structures such as the neocortex have developed to support complex behaviors, social interactions, and higher cognitive functions, allowing species to adapt to their environments and enhance survival.

Question 44

Apply learning of functions of the cortical lobes to determine and describe which structure has been damaged in hypothetical patients

Answer 44

• Frontal Lobe Damage: Impairs decision-making and impulse control, potentially leading to personality changes.
• Parietal Lobe Damage: Results in difficulties in spatial awareness and sensory perception.
• Temporal Lobe Damage: May lead to memory loss or difficulties in understanding language.
• Occipital Lobe Damage: Can cause visual impairments or hallucinations.

Question 45

Differentiate the functions associated with each hemisphere

Answer 45

• Left Hemisphere: Typically associated with language, analytical thinking, and logical reasoning.
• Right Hemisphere: Involved in spatial abilities, face recognition, emotional processing, and creativity.

Question 46

Identify why cerebral lateralization is advantageous

Answer 46

Cerebral lateralization allows for specialization of function, leading to more efficient processing of information. For example, language processing is primarily handled by the left hemisphere, freeing the right hemisphere to manage spatial tasks and emotional understanding.

Question 47

Identify accurate and problematic characterizations of cerebral lateralization

Answer 47

• Accurate: Different functions are often more pronounced in one hemisphere; for example, language is predominantly in the left hemisphere for most right-handed individuals.
• Problematic: Oversimplifications can arise, such as the notion that individuals are strictly “left-brained” (logical) or “right-brained” (creative), which does not reflect the complexity of brain function and interaction.

Question 48

Identify how split brain patients have contributed to our understanding of cerebral lateralization

Answer 48

Split-brain patients, whose corpus callosum has been severed, have shown that each hemisphere can function independently. This has provided insight into how different cognitive functions are lateralized, revealing, for instance, that the left hemisphere processes language while the right is better at visual and spatial tasks.

Question 49

Identify an differentiate between structural and functional neuroimaging

Answer 49

• Structural Neuroimaging: Techniques (like MRI and CT scans) that provide images of brain structure and anatomy. Useful for identifying tumors, injuries, or structural abnormalities.
• Functional Neuroimaging: Techniques (like fMRI and PET scans) that measure brain activity by detecting changes associated with blood flow or metabolic processes. Useful for understanding brain activity related to specific tasks or functions.

Question 50

Identify and differentiate between neuroimaging techniques

Answer 50

• MRI (Magnetic Resonance Imaging): Provides high-resolution images of brain structures.
• fMRI (Functional MRI): Measures brain activity by detecting changes in blood flow.
• CT (Computed Tomography): Provides cross-sectional images of the brain.
• PET (Positron Emission Tomography): Measures metabolic activity in the brain using radioactive tracers.
• EEG (Electroencephalogram): Records electrical activity of the brain via electrodes on the scalp.

Question 51

Identify the most appropriate neuroimaging technique to use for real-world medical or research examples

Answer 51

For assessing brain structure, MRI is preferred. For studying brain activity during cognitive tasks, fMRI is most suitable, as it provides both spatial and temporal resolution.

Question 52

Identify best practices and limitations for interpreting fMRI data

Answer 52

• Best Practices: Use appropriate controls, ensure proper statistical analysis, and consider individual variability.
• Limitations: fMRI measures indirect indicators of brain activity (blood flow changes) rather than neuronal firing directly, and it has lower temporal resolution compared to techniques like EEG.

Question 53

Identify and differentiate the techniques that are able to infer causal relationships between brain activity and behaviour

Answer 53

• Transcranial Magnetic Stimulation (TMS): Can disrupt or enhance brain activity in specific areas, helping to infer causal relationships.
• Optogenetics: Allows for precise control of neuronal activity using light, enabling researchers to determine the effects of activating or inhibiting specific neurons on behavior.
• Lesion Studies: Observing behavioral changes following brain lesions can help establish causal links between specific brain areas and functions.