Biol 166 Final

  1. Coordinated Movement vs
    Coordinated Muscle Contraction
    Muscles & neurons control muscle movement

    Spinal cord controls coordinated muscle contraction
  2. Somatic Musculature (3)
    • Axial muscles
    • Proximal muscles
    • Distal muscles
  3. Axial muscles
    trunk movement & posture
  4. Proximal muscles
    • Shoulder, elbow, pelvis, knee
    • (locomotion)
  5. Distal Muscles
    • Hands, feet, digits
    • Fine motor skills
  6. 2 Types of Motor Neurons
    • 1. Alpha
    • 2. Gamma
  7. Alpha Motor Neurons
    • Single motor neuron innervates multiple muscle fibers. Increased frequency of AP results in fine movement. Low frequency of AP results in twitch.
    • *Recruitment
    • **Varying firing rate
  8. 3 Types of Input of Alpha Motor Neuron
    • 1. input from spinal interneurons
    • 2. sensory input from muscle spindles
    • 3. input from upper motor neurons in the brain
  9. Red Motor Units
    • Large # mitochondria and enzymes
    • Slow to contract but sustain contraction
    • *Slow fatiguing
  10. White Motor Neurons
    Few mitochondria, anaerobic metabolism, rapidly fatiguing
  11. Hypertrophy vs Atrophy
    • Hypertrophy- exaggerated growth
    • Atrophy- degeneration
  12. Muscle Contraction
    • 1. Alpha motor neuron releases ACh
    • 2. Large EPSP in muscle fibers via nicotinic ACh receptors
    • 3. AP
    • 4. Ca2+ release
    • 5. Fiber contracts
    • 6. Relaxation due to Ca2+ reuptake by organelles that originally released it
  13. ACh-ase Inhibitors
    reduce breakdown of ACh to increase muscle movement and contraction

    Often used in combination with cholesterol drugs or when treating Alzheimers since ACh neurons are some of the first affected.
  14. Muscle fiber calcium channels
    • Has a tetrad of calcium channels
    • At rest- no net movement of calcium
    • When depolarized- calcium is released into T tubule space
  15. Sliding Filament Model
    • 1. calcium binds to troponin
    • 2. causes myosin to bind to actin
    • 3. myosin head pivots, causing filament to slide
    • 4. continues until all calcium is used up and ATP is present
    • 5. Relaxation- goes back to resting potential, calcium is removed by ATP driven pump
  16. Rigor mortis
    • Can't generate ATP to cause relaxation
    • ex. Na+ is used to reverse rigor mortis in turkey
  17. Amyotrophic Lateral Sclerosis (ALS)
    • symptoms- weakness in one arm/leg. If starts on left arm, will then swith to right limb.
    • high correlation between playing sports and ALS
  18. Which is the most important factor affecting the onset of familial ALS symptoms?

    C) genetics
  19. Reactive Oxygen Species (R.O.S.)
    • 1. Superoxide anion (O2-): in mitochondria
    • 2. Hydrogen peroxide (H2O2): summons immune response
    • 3. Hydroxyl radical (HO-): uneven # of e-, very reactive because will take e- from proteins
  20. R.O.S. Effects
    • 1. Damage DNA
    • 2. Attack lipid membrane causing leaks
  21. Examples of antioxidants
    vitamin E, vitamin C, beta carotine
  22. ALS DNA
    Point mutation in antioxidant enzyme: SOD
  23. SOD
    • Very abundant (1% of total cell protein)
    • Even cows and yeast produce as much SOD as humans
    • Needs to bind copper and zinc (point mutations affect this)
  24. Copper & Zinc
    • bind superoxide, is reduced by taking an electron.
    • CuZnSOD- enzyme that gets rid of SOD
    • CuZnSOD can react with H2O2 to make OH-
  25. Which is the most important factor affecting the progression of ALS?

    A) medication
  26. Imbalance of oxidative species in lower motor neuron causes______
    premature aging, immunodeficiencies, and neurological disorders
  27. Lower Motor Neuron vs Upper Motor Neuron
    • Lower motor neuron: Innervated by ventral horn of spinal cord
    • Upper motor neuron: Supplies input to the spinal cord
  28. Stretch Receptors
    Allow feedback loop / sensory feedback in the body
  29. ALS Mutants
    • The FALS-associated mutants of CuZnSOD show a diminished ability to segregate and bind copper & zinc in their proper sites.
    • The mutants have an increased ability to use hydrogen peroxide as a substrate (peroxidative activity)
    • The alternative function of mutant SOD is mediated by mismetallation.
    • A downstream consequence of the mutants is the generation of an abnormal biochem rxn that may mediate loss of motor function.
  30. Proprioceptors
    • Stretch receptors
    • Group 1a axons
  31. Myotatic Reflex
    • When a muscle is pulled, there is a tendency to pull back
    • "stretch reflex"
    • When stretched, the discharge of the 1a axon increases
    • *monosynaptic
  32. Knee Jerk Reflex
    • 1. Muscle is stretched
    • 2. 1a axon (proprioceptor) responds
    • 3. alpha motor neuron fires
    • 4. muscle begins to contract
  33. Discharge Rate of Sensory Axons is Related to...
    muscle length
  34. Muscle Spindles (2 Types of Fibers)
    • 1. Intrafusal fibers: gamma
    • 2. Extrafusal fibers: alpha
  35. Intrafusal fibers: gamma motor neurons
    when activated, a vibration occurs which affects the proprioceptor
  36. Extrafusal fibers: alpha
    When activated, the extrafusal fiber contracts
  37. Fine Motor Movement Uses Which Fibers
    Both alpha and gamma
  38. Excitation-Contraction Coupling:
    Gamma Loop
    • Changes set point of the myotatic feedback loop
    • Provides additional control of alpha motor neurons and muscle contraction
    • Circuit: Gamma motor neuron > intrafusal muscle fiber > Ia afferent axon> alpha
  39. Muscle Tension Gauge
    • Want to be able to detect weight
    • Proprioception from Golgi Tendon Organs is in series
  40. Reverse Myotactic Reflex
    • Regulates muscle tension within an optimal range
    • Acts: IV axon is hooked to extrafusal fiber. Alpha motor neuron > Golgi tendon organ > 1b axon (*doesn't act on intrafusal fiber)
  41. Other types of proprioceptors are found in joint
    • respond to angle, velocity, and direction of joint movement
    • The info from joint receptors is combined with muscle spindle (tension load), golgi tendon organs, and skin receptors
  42. Spinal Interneurons
    Synaptic Inputs:
    • Primary sensory axons
    • Descending axons from brain
    • Collaterals of lower motor neuron axons
  43. Inhibitory Input
    • Reciprocal inhibition: Contraction of one muscle set accompanied by relaxation of antagonist muscle
    • Example: Myotatic reflex
    • This reciprocal inhibition allows for greater movement
  44. Excitatory Input
    Flexor reflex:
    Complex reflex arc used to withdraw limb from aversive stimulus
  45. Excitatory Input
    Crossed-extensor reflex:
    Activation of extensor muscles and inhibition of flexors on opposite side
  46. Walking
    • A series of excitatory and inhibitory neurons
    • *Inhibitory neurons allow for APs to be generated at different times
    • 1. glutamate binds to receptor
    • 2. Calcium and Sodium enter
    • 3. EPSP
    • 4. Potassium rushes out and Magnesium enters to return to resting potential
  47. Video: Animation Based on Movement
    • Artificial Evolution teaches stick figure to walk
    • Medical Implication: Look at motor response to stimuli before trying on a person
  48. X vs Y Chromosomes
    • X contains 1500 genes
    • Y contains 50 genes
  49. SRY
    • Sex-determining Region on Y Chromosome
    • encodes TDF (testis-determining factor)
  50. Concept of Gender Based On
    • Society
    • Genetics
    • Hormones
  51. Sexual Development and Differentiation
    • Differentiation of fetus and development of gonads
    • Structures in the gonad: Müllerian duct and Wolffian duct
    • Hermaphroditism. Cause: External
    • genitals develop from undifferentiated urogenital structures
  52. Sex Hormones
    • Steroids released by endocrine gland, but regulated by the pituitary
    • Altered cholesterol structure
    • Male= testosterone
    • Female= estradiol
  53. Importance of steroid hormones
    steroid hormones can pass through the cell membrane
  54. Areas of largest sex hormone concentration
    • Hypothalamus
    • Preoptic area
    • Pituitary
  55. Hormonal Control in Males
    • Testes release androgen. This increases at puberty which leads to the development of secondary sex characteristics
    • Hormone levels fluctuate daily
    • Correlates (but not causes) aggression
  56. Hormonal Control In Females
    Ovaries release estradiol and progesterone. This fluxuates based on the menstrual cycle
  57. Gonadotropins (LH and FSH)
    In males, LH produces testosterone and FSH aids in maturation of sperm cells

    In females, LH & FSH cause estrogen secretion
  58. Neural Basis for Sexual Behavior
    • Neurotransmitters relax smooth muscle
    • -NO acts as a vasodilator to increase blood flow
    • -ACh and VIP (vasoactive intestinal polypeptide) also contribute in muscular contraction for orgasm/ejaculation
  59. Voles as an animal model for sex hormones
    • Prairie voles- family values
    • Meadow voles- asocial and promiscuous

    • *Increased vasopressin causes males to show increased paternal activity
    • *Increased oxytocin stimulates maternal behavior in female voles
  60. Spatial Reasoning (gender differences)
    females have better spatial reasoning (shapes) than men due to lower estrogen levels
  61. How do steroids influence neurons
    • 1. alter membrane excitability / sensitivity to NTs. This causes more release of NTs
    • 2. Modulates enzyme function
    • 3. Bind to specific receptors in cytoplasm or nucleus
  62. Cyclooxidase (COX) Inhibitors
    • COX is an enzyme. Inhibitors:
    • -reduce copulatory behavior in male rats
    • -make female rats have male-like copulatory behavior
    • -Used to reduce pain
  63. Organizational vs Activational Effects of Hormones
    • Organization Effects- Irreversible
    • Activation Effects- Temporary
  64. Mismatch between genetic sex and hormone sex
    - treat men with testosterone to reduce female features
  65. Androgen-Insensitive Genetic Males
    defective androgen gene on X chromosome
  66. Congenital Adrenal Hyperglasia Genetic Females
    Abnormally large
  67. Gynandromorphic
    • Have both male & female tissue
    • ex. Zebra fynch have female left brain and male right brain based on hormone concentration
    • *hormone control can alter their songs
  68. Activational Effects of Sex Hormones
    • -Estradiol causes more outgrowth of neurite. These increases will increase activation of synapse
    • -Men: Rise in testosterone, anticipation of sex, fall in testosterone, decreased sexual interest
    • -Women: Rise in estrogen, increased sexual interest
  69. The Brain In Love Video
    • Ventral Techno Area (VTA)- part of brains reward system for wanting/craving
    • -similar to cocaine high
    • -activity in brain calculates gains and losses
  70. Mood
    Emotion extended over time
  71. Cannon-Bard Theory of Emotion
    • Emotional experience can occur independently of emotional expression.
    • *Thalamus plays a key role in sensations: ex. See snake > response in thalamus > emotional response.
  72. James-Lange Theory of Emotion
    • We experience emotion in response to physiological change
    • *nothing occus at unconscious level
    • ex. we are sad because we cry
  73. Thalamus & Hypothalamus
    • Thalamus- heart shaped area in middle of brain
    • Hypothalamus is right below
  74. Processing Emotional Info
    • Inputs: touch, sight, hearing
    • Outputs: emotional experience & behavioral response
  75. Broca's Limbic Lobe
    • limbic system. Everything around the main cortex area/corpus collosum
    • *Forms ring around brainstem ("limbic"=border)
  76. Papez Circuit
    • Links cortex to hypothalamus
    • *Hippocampus is related to emotion
    • *Rabies=hyperemotional response
    • *Phineas Gage= iron rod through frontal lobe. went from friendly to aggressive
  77. Lesions in thalamus
    often lead to emotional disorder
  78. Which of the following statements reflects the argument against a discrete emotion system?

    C) Solid evidence indicates that some structures involved in emotion are also involved in other functions.
  79. Kluver-Bucy Syndrome
    • Temporal lobectomy in rhesus monkeys
    • decreased fear & aggression
    • decreased vocalization & facial expressions
    • *In humans- flattened emotions, inability to recognize facial expressions
  80. Amygdala
    • 2 areas just below the thalamus
    • related to fear and aggression
    • *bilateral amygadalectomy- reduce fear & aggression
  81. Electrical stimulation of amygdala
    Increased vigilance or attention
  82. Autonomic Nervous System
    1. Sympathetic- increase heart rate & blood pressure, depressed digestive tract, mobilization of glucose reserves (flight response)

    2. Parasympathetic- slower heart rate, increased digestive activity (vomit or diarrhea), stop sweating/cold sweats (ex. faint)

    *Can have sympathetic and parasympathetic response at same time
  83. Predatory Aggression
    • few vocalizations
    • will attack head/neck
    • No activity in sympathetic divisions of ANS
  84. Affective Aggression
    • Used for show/ not kiling or food
    • Make vocalizations or threatening postures
    • High sympathetic activity
  85. Removal of Amygdala
    • Symptoms
    • -Reduced aggressive asocial behavior
    • -Increased ability to concentrate
    • -Decreased hyperactivity
  86. The Hypothalamus and Aggression
    • Removal of cerebral hemispheres
    • -Sham rage (extreme aggressive behavior)
    • -Behavior reversed by small lesions in hypothalamus
    • -Specific lesions, posterior hypothalamus in fear, aggression behaviors
  87. The Midbrain and Aggression
    Two pathways
    • 1. Hypothalamus sends signals to brain stem
    • 2. Medial forebrain bundleDorsal longitudinal fasciculus
  88. Serotonin
    • Neurotransmitter that regulates aggression. Found in Raph Nuclei of brain stem.
    • -lipophilic
    • -decrease in reuptake induces aggression in rodents housed together
    • -PCP blocks serotonin synthesis
  89. Vervet monkeys were injected with drugs that either increased or decreased serotonergic activity. These experiments showed which of the following about the relationship between serotonin and aggression?

    A) More aggression is associated with less serotonergic activity
  90. Cleft Pallet
    Still visual learning, but don't understand language
  91. Memories range from stated facts to ingrained motor patterns (examples of both)
    • 1. stated facts- memorized things
    • 2. ingrained motor patterns- tie shoe, open door
  92. Learning vs Memory
    • Learning- acquisition of new facts
    • Memory- retention of learned information
  93. Memories are stored over time (2 types)
    • 1. Explicit (declarative)- facts & events
    • 2. Implicit (non-declarative)- procedural memory; skills, habits, behaviors
  94. Long Term
    Short Term
    Working Memory
    • Long term- from consolidation of short term
    • Short term- from sensory info
    • Working memory- temporary info storage
  95. Amnesia
    • Serious loss of memory and/or ability to learn
    • caused by: concussion, chronic alcoholism, tumor, stroke
  96. Limited Amnesia vs Transient Global Amnesia
    Limited amnesia: common. block out small chunks of time

    Transient Global amnesia: short period of anterograde amnesia
  97. Retrograde vs Anterograde
    • Retrograde: forget things you know
    • Anterograde: Can't form new memories
  98. Hobb Model
    • External events are represented by cortical cells
    • -Synaptic connection of cortical cells are reciprically interconnected (reverberation)
    • -"fire together, wire together"
    • -Engram can have widely distributed cells in assembly, could involve nurons of sensation and perception
  99. Penfield's Experiments
    Electrical stimulation of the temporal lobe to get complex sensations (hallucinations and ability to recall past experience)
  100. Temporal Lobe
    • Role in memory storage
    • stimulation of temporal lobe is different from stimulation of other areas of neocortex
    • Temporal Lobectomy=anterograde amnesia
  101. Temporal Lobes & Declarative Memories
    If rate exits maze at certain areas with food, will learn to only exit at those areas

    If rat in water maze with platform for exit, will learn where platform is and go straight there
  102. Relational Memory
    • Knows relative location to objects/shapes around it
    • Also learn how objects are linked (ex. placing book inside backpack)
  103. Hypothesis of Hebb
    memories result from synaptic alterations
  104. Habituation vs Sensitization
    Habituation- learning to ignore stimulus that lacks meaning (getting bored in class)

    Sensitization- learning to intensify response and stimulus (told there will be an exam and then pay attention)
  105. Associative Learning
    • Classical conditioning- Pavlov
    • Also use sinple invertebrate systems to study (ex. aplysia & habituation of gill withdrawal reflex)
  106. Tone
    Spatial Location
    • Tone - note
    • Pitch - frequency of tone
    • Rhythm - repeating patterns: contrasts of silence and sounds
    • Tempo - fast vs slow speed
    • Contour - ups and downs of melody
    • Timbre - sounds from different instruments and voices
    • Loudness - volume
    • Spatial Location - where it's coming from
    • Reverberation - echo (when singing or moving hand on instrument)
  107. Left Brain
    language, analytical thinking, math, logic
  108. Right Brain
    • Spatial reasoning, art appreciation, intuition
    • *important for music when young, however when an adult will integrate right and left brain
  109. Frontal Lobe
    Parietal Lobe
    Temporal Lobe
    Occipital Lobe
    • Frontal Lobe- execute function
    • Parietal Lobe- touch, sensation, body positioning
    • Temporal Lobe- hearing, speach, spoken language
    • Occipital Lobe- vision
  110. Synesthesia
    hear music and see images
  111. 3 Domains of Learning
    • 1. Cognitive - knowledge / spatial reasoning
    • 2. Psychomotor- skills & movement
    • 3. Affective- emotions / feelings
  112. Sight Reacting
    adept musicians can see music in brain
  113. Chunking
    • Increased ability to learn something by breaking it down into pieces. In music, learn a phrase/bar at a time.
    • *An example of short term memory
  114. Meaningful Learning
    • Long term
    • Anchored memory:
    • - take small bits and link together OR take large piece of music and associate with something else (ex. can't get song out of head)
  115. Psychomotor Skills
    • More in frontal and temporal lobe
    • 1. Broca's area- left temporal lobe. Damage= expressive aphasia (can understand language but can't speak it)

    2. Wernicke's area- next to Broca's area in frontal temporal lobe. Damage= receptive aphasia (unable to understand language)
  116. Expressive Aphasia vs Receptive Aphasia
    • Expressive aphasia- can understand language but can't speak it
    • Receptive aphasia- unable to understand language

    *just because can't speak or understand, can still take in music and play it back
  117. Conduction Aphasia
    • lesion between Broca's area & Wernicke's area. Person is told something, they understand it, but can't repeat it back.
    • *can converse regularly, just can't repeat back
  118. Musician's Brain
    • 1. 25% increase in auditory nerve cells (can process complex tones)
    • 2. Enlarged cerebellums which affect precise timing and accuracy of motor commands (play right note at right time)
    • 3. Enhanced or enlarged Wernicke's area. Gives "perfect pitch"
  119. Music can combine thalamus, hypothalamus, and amygdala?
    Amygdala is not affected by music. Other 2 are
  120. 1. Why are lower motor neruons called the "final common pathway" for behavioral control?

    A. they are the output of the motor system
  121. Which is the first step in the contraction phase of the excitation-contraction coupling?

    B. calcium binds to troponin
  122. Why does neuromuscular transmission fail in myasthenia gravis?

    B. autoantibodies interfere with the function of nicotinic ACh receptors at the neuromuscular junction
  123. What type of motor neurons ensures that the spindle continues to provide information about muscle length during muscle contraction?

    D. gamma motor neurons
  124. Which reflex prevents you from falling when you suddenly lift your foot off the ground in response to pain?

    B. crossed-extensor reflex
  125. Which of the following describes the function and loction of the golgi tendon organs?

    A. monitor muscle tension, situated in series with muscle fibers
  126. What is recipricol inhibition?

    A. the contraction of one set of muscles is accompanied by the relaxation of the antagonist muscles
  127. What are central pattern generators?

    C. the motor units of a given muscle
  128. Copper-zinc superoxide dismutase is involved in which function(s)?

    A. the removal of superoxide anion (ROS) in the cell
  129. Familial ALS, as opposed to sporadic ALS, is related to which major factor?

    B. genetics
  130. What is the basis of X-linked disorders?

    B. defect in the single X chromosome in males
  131. At what point in development is gender determined?

    C. fertilization
  132. During what developmental period are the gonads undifferentiated?

    B. the first 6 weeks of gestation
  133. Which of the following is a caveat about sexual dimorphisms of cognition in humans?

    B. huge variation results from differences among individuals rather than being gender-specific
  134. Which of the following DNA manipulations has been used to change the gender of a mouse?

    A. incorporating an SRY gene
  135. Steroid hormones have both organizational and activational effects. Which is an example of the organizational effect of steroid hormones?

    B. Wolffian duct develops into the male reproductive organs
  136. The testes produce andogens, which trigger the masculinization of the nervous system early in development by which of the following mechanisms?

    A. regulating the expression of a variety of sex-related genes
  137. Female concentrations of testosterone are roughly 10% of those found in males (T/F)
  138. Steroid hormones are fatty and can easily pass through the cell membranes and bind to receptors within the cytoplasm, giving them direct access to the nucleus and gene expression (T/F)
  139. Testosterone is produced only in the testes (T/F)
  140. What is the Cannon-Bard theory of emotion?
    a. emotional experience is a response to physiological changes in the body
    b. emotional experience can be independent of emotional expression
    b. emotional experience can be independent of emotional expression
  141. What is the most common symptom of amygdala lesions in humans?

    B. Inability to recognize the facial expression of fear
  142. Which of the following statements reflect the argument against a discrete emotion system?

    A. solid evidence indicates that some structures involved in emotion are also involved in other functions
  143. Which of the following is strong evidence linking the amygdala with fear?

    C. bilateral amygdalectomy profoundly reduces fear and aggression
  144. In the proposed neural circuit for learned fear, the state of the ANS is altered by what neural connection?

    B. efferents from the central nucleus of the amygdala project to they hypothalamus
  145. Electrical stimulation of the amygdala elicits what response in humans?

    B. increased anxiety and fear
  146. The proposed circuit of learned fear suggest that the autonomic response to a fearful stimulus is mediated by the hypothalamus (T/F)
  147. The brain areas that are activated by listening to music are the same areas in the brain involved with:

    D. all of the above
  148. Listening to music recruits neural mechanisms similar to those associated with fear (T/F)
  149. Which of the following statements correctly reflects the idea of memory consolidation?

    C. memory consolidation converts short term memories or sensory information into long term memory
  150. A patient with brain trauma cannot remember events prior to the trauma. Which amnesia does this sympton indicate?

    A. retrograde amnesia
  151. Karl Lashley studied the effects of various sized cortical lesions on maze performance in rats. He concluded that the memory deficits were correlated with the size of the lesions not the location, and that all cortical areas contribute equally to learning and memory. What is the current interpretation of these experiments?

    D. All cortical areas do not contribute equally to memory, but memories are widely distributed
  152. What are hippocampel place cells?

    A. neurons that fire when the animal is in a specific location
  153. Which of the following describes procedural learning?

    C. a motor response (procedure) in reaction to a sensory input
  154. Which of the following represents Marr-Albus theory of motor learning?
    a. input form the mossy fibers relaying information from the pons determines plasticity of the Purkinje cell connections
    b. the parallel fiber synapse on the Purkinje cell dendrite is plastic if it is active at the same time as climbing fiber input to the Purkinje cell
    • b. the parallel fiber synapse on the Purkinje cell dendrite is plastic
    • if it is active at the same time as climbing fiber input to the
    • Purkinje cell
  155. LTP and LTD in CA1 of the hippocampus may reflect the bidirectional regulation of which two processes?

    C. phosphorylation and the number of postsynaptic AMPA receptors
Card Set
Biol 166 Final