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Biological Bases Unit Review

Interaction of Heredity and Environment

  • Heredity

    • the manner in which characteristics and traits are passed on from parents to their offsprings

  • Nature

    • the biological/genetic predispositions that impact one's human traits — physical, emotional, and intellectual

  • Nurture

    • all of the external or environmental factors that affect human development

  • Genetic predisposition

    • to be susceptible to it or more likely to encounter it due to inherited genes

  • Evolutionary perspective

    • to be susceptible to it or more likely to encounter it due to inherited genes

    • Charles Darwin

  • Natural selection

    • process by which biologically influenced characteristics become either more or less common in a population depending on how those characteristics affect an individual's reproductive fitness — the passing of genes on to future generations.

  • Eugenics

    • practice or belief system that aims to improve the human species by selectively breeding individuals with desirable traits, often by encouraging reproduction among those considered "superior" and discouraging reproduction among those deemed "inferior," which is widely considered unethical due to its discriminatory and harmful potential based on subjective criteria of "desirable" traits. 

  • Twin studies

    • practice or belief system that aims to improve the human species by selectively breeding individuals with desirable traits, often by encouraging reproduction among those considered "superior" and discouraging reproduction among those deemed "inferior," which is widely considered unethical due to its discriminatory and harmful potential based on subjective criteria of "desirable" traits. 

  • Family studies

    • practice or belief system that aims to improve the human species by selectively breeding individuals with desirable traits, often by encouraging reproduction among those considered "superior" and discouraging reproduction among those deemed "inferior," which is widely considered unethical due to its discriminatory and harmful potential based on subjective criteria of "desirable" traits. 

  • Adoption studies

    • research studies that compare an adopted person's behavior to both their biological and adoptive parents' behavior

 

Overview of the Nervous System

  • Central nervous system (brain and spinal cord)

    • coordinates action and interactions of the other systems in the body

    • brain and spinal cord

    • brain is dominate

  • Peripheral nervous system

    • somatic and autonomic

    • connects CNS to rest of body

  • Autonomic nervous system

    • controls involuntary functions

    • consists of sympathetic and parasympathetic

  • Sympathetic nervous system

    • fight or flight (or freeze)

  • Parasympathetic nervous system

    • default

    • return to homeostasis

  • Somatic nervous system

    • voluntary movement

 

The Neuron and Neural Firing

  • Neurons

    • transmit and receive information

  • Glial cells

    • structure, isolation, communication, waste transport, building blocks to everything

  • Reflex arc

    • spinal cord

    • interneurons

    • receive from brain and send to motor neurons

  • Sensory neurons

    • skin stimulated

  • Motor neurons

    • muscle activated

  • Interneurons

    • neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

  • Neural transmission

    • The transfer of information between neurons

  • Action potential

    • shift in electrical energy that develops a nerve impulse

  • All-or-nothing principle

    • shift in electrical energy that develops a nerve impulse

  • Depolarization

    • when a positively charged chemical moved inside, a neuron is charged or activated

  • Refractory period

    • once a neuron fires, a brief period begins where it cannot fire again until the ions return to normal

  • Resting potential

    • unactivated state of the neuron

  • Reuptake

    • neurotransmitter’s reabsorption by the sending neuron

  • Threshold

    • a change occurs in the electrochemical balance inside and outside the neuron to allow it to reach an amount of intensity to fire

  • Multiple sclerosis

    • if myelin sheath degenerates communication to muscles slows eventual loss of muscle control

  • Myasthenia gravis

    • chronic autoimmune disorder that affects the neuromuscular junction, the point where nerves meet muscles. 

  • Excitatory neurotransmitters

    • excites the neuron and cause message to be sent to next neuron

  • Inhibitory neurotransmitters

    • prevent message from being passed on further

  • Dopamine

    • influences movement, learning, attention and emotion/mood

    • neurotrasnmitter

  • Serotonin

    • regulates mood and emotional state; regulation of sleepwake cycle

    • neurotransmitter

  • Norepinephrine

    • helps control alertness and arousal

    • neurotransmitter

  • Glutamate

    • major excitatory neurotransmitter involved in memory

    • neurotransmitter

  • GABA

    • major inhibitory neurotransmitter

  • Endorphins

    • natural opiate-like neurotransmitters linked to pain control and pleasure

  • Substance p

    • modulation of pain

    • neurotransmitter

  • Acetylcholine

    • enables muscle action, learning, memory

  • Hormones

    • chemical messengers that re manufactured by the endocrine glands travel through the bloodstream and affect other tissues

  • Adrenaline

    • fight or flight

    • hormone

  • Leptin

    • hunger suppressant

    • hormone

  • Ghrelin

    • hunger stimulation

    • hormone

  • Melatonin

    • sleep

    • hormone

  • Oxytocin

    • labor, lactation, love

    • hormone

  • Psychoactive drugs

    • depressants, stimulants and hallucinogens

  • Agonists

    • will bind to a receptor and mimics the neurotransmitter’s effect

  • Antagonists

    • will bind to receptor and block a neurotransmitter’s function

  • Reuptake inhibitors

    • enhances the effect of a neurotransmitters

  • Stimulants

    • increased neural activity

  • Caffeine

    • stimulant

  • Cocaine

    • a powerful and addictive stimulant, derived from the coca plant, producing temporarily increased alertness and euphoria

  • Depressants

    • decreased neural activity

  • Alcohol

    • depressant

  • Hallucinogens

    • distortions in perception and/or cognition

  • Marijuana

    • hallucinogen

    • enhanced sensation, relief of pain, distortion of time, relaxation

  • Opioids

    • pain relievers, euphoria, relaxation

  • Heroin

    • opioid

  • Tolerance

    • diminishing effect with regular use of the same dose of a drug requiring the user to take larger and larger doses before experiencing the drugs effect

  • Addiction

    • continued substance craving and use despite significant life disruption and/or physical risks

  • Withdrawal

    • abruptly stopping drug use effects

 

The Brain

  • Brain stem

    • oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions

  • Medulla

    • the base of the brainstem; controls heartbeat and breathing

  • Reticular activating system

    • network of neurons in the brainstem that plays a crucial role in regulating arousal, consciousness, and attention. 

  • Reward center

    • nucleus accumbent

  • Cerebellum

    • the “little brain” at the rear of the brainstem; functions include processing sensory input, coordinating movement output and balance and enabling nonverbal learning and memory

  • Cerebral cortex

    • intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body’s ultimate control and information processing center

  • Limbic system

    • between oldest and newest brain areas

    • contains amygdala, hypothalamus, hippocampus

  • Thalamus

    • brain’s sensory control center, located on top of brainstem; it directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

  • Hypothalamus

    • neural structure lying below the thalamus; it directs several maintenance activities (homeostasis), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward

  • Pituitary gland

    • endocrine system’s most influential gland, regulates growth and controls other endocrine

    • include by hypothalamus

  • Hippocampus

    • processes conscious memories

  • Amygdala

    • two lima bean sized neural clusters in the limbic system; linked to emotion (aggression and fear)

  • Corpus callosum

    • the large band of neural fibers connecting the the two brain hemispheres and carrying messages between them

  • Occipital lobes

    • portion of cerebral cortex lying at the top of the head towards the rear; receives sensory input for touch and body position

  • Temporal lobes

    • portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

  • Parietal lobes

    • portion of the cerebral cortex lying at the top of the head towards the rear; receives sensory input for touch and body position

  • Association areas

    • areas of the cerebral cortex that are not involved in primary m motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking and speaking

  • Somatosensory cortex

    • area at the front of the parietal lobes that registers and processes body touch and movement sensations

  • Frontal lobes

    • portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements

  • Linguistic processing

    • Wernicke’s area

  • Higher-order thinking

    • process that requires complex manipulation

  • Executive functioning

    • skills that allow you to plan everyday tasks

  • Prefrontal cortex

    • forward part of the frontal lobes enables judgment, planning and processing of new memories

  • Motor cortex

    • an area at the rear of the frontal lobes that controls the voluntary movements

  • Split brain research

    • when two hemispheres can’t communicate, each side seems to act independently almost like other side doesn’t exist

  • Hemispheric specialization

    • hemisphere performs ints own primary set of functions

  • Broca’s area

    • damages disrupts speaking

  • Wernicke’s area

    • damage disrupts understanding

  • Aphasia (Broca’s and Wernicke’s)

    • impacts ability to communicate

  • Contralateral hemispheric organization

    • left: actions of right side of the body, language and cognitive skills

    • right: actions of the left side of the body, intuitive, spatial, creative tasks

  • Plasticity

    • the brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

  • EEG

    • electrical activity

    • function

    • sleep stages

  • fMRI

    • oxygen consumption

    • structure and function

    • levels of activity

  • Lesioning

    • distortion of or damage due to injury, disease, surgery, drugs, stimulation

 

Sleep

  • Consciousness

    • wakefulness and sleep

    • our awareness of ourselves and our environment

  • Circadian rhythm (sleep/wake cycle)

    • 24.5 hours

    • biological clock; regular body rhythms

  • Jet lag

    • sleep disruption when you cross time zones that disrupts biological clock

  • Shift work

    • time of day for work shifts

  • NREM stage 1

    • transition between awake and sleep

    • lasts 5-10 minutes

  • Hypnogogic sensations

    • occur as you enter stage 1

    • vivid dream-like experiences/hallucinations

    • involves sense

    • when you begin to fall asleep and shoot up

  • NREM stage 2

    • body temperature drops and heart rate slows

    • brain begins to slow

    • brain begins to produce sleep spindles

    • lasts approximately 20 minutes

  • NREM stage 3

    • muscles relax

    • blood pressure and breathing rate drop

    • deepest sleep occurs

  • REM sleep

    • most important

    • brain becomes active

    • body becomes relaxed and immobilized

    • dreams occur

    • eyes move rapidly

  • REM rebound

    • occurs when deprived of REM sleep and body compensates for it by increasing REM sleep duration

  • Activation-synthesis (dreams)

    • Suggests that dreams are the result of the brain's attempt to make sense of random neural activity during sleep.

  • Consolidation theory (dreams)

    • the brain processes and organized new information which may manifest as dreams

  • Memory consolidation

    • highlights the importance of REM sleep for memory retention

  • Restoration of resources

    • helps restore physiological functions

      • restores mental processes

  • Insomnia

    • inability fall asleep or stay asleep hours

  • Narcolepsy

    • person falls into REM sleep during waking

    • excessive daytime sleepiness

    • cataplexy

      • sudden loss of muscle tone

  • REM sleep behavior disorder

    • body is not motionless or “paralyzed” during REM sleep and the person can physically act out dream behavior

  • Sleep apnea

    • sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

  • Somnambulism

    • sleepwalking

    • occurs in NREM Stage 3