Neurophysiology, Muscular

1
Neurophysiology, Muscular the Senses

• Chapter 48 49

2
Processing a Stimulus

• A form of energy that must be converted to and
  transferred to specialized cells Neurons
• Special Neurons Sensory receptors have four
  basic functions
• Sensory transduction creates membrane potential
• Amplification makes the stimulus stronger
• Transmission achieved with action potentials
• Integration process information by summation

3
Sensory Receptors to Detect Stimuli

• General Receptors Catagories
• Interoreceptors Exteroreceptors
• (comes from inside) (comes from the outside)
• Mechanoreceptors Propioreceptors (stretch)
• Chemoreceptors (chemicals)
• Thermoreceptors (heat)
• Electroreceptors (energy)
• Photoreceptors (light)
• Nocioreceptors (pain prostaglandins)
• Baroreceptors (pressure)

4
Mechanoreceptors (pg. 1048)

• Detects
• -touch (tactile) -pressure (sound)
• -stretching -movement
• -gravity -waves (water, sound)
• -Body position
• Key structures and receptors found in skin
• Pacinian Meissner corpuscles
• Proprioreceptors stretch, tension movement in
  muscles
• Joint receptors movement of bones ligaments
• Mechanoreceptors body position

5
Receptors in the Skin (pg. 1048)
6
Nocioreceptors
7
Video 2 The Neural Connection

• Segment 1
• Name three types of sensory neurons mentioned by
  Dr. Peter Narins
• Where are the chemoreceptors located in lobsters?
• Where is there a high concentration of
  thermoreceptors located in a snake? Why are they
  located in this region?
• Name the key parts of a neuron (nerve cell).
• Name the key ions required for an action
  potential (nerve impulse) to occur.
• Write FIVE key statements mentioned for this
  segment.
• BE sure to number your statements

8
Introductory Questions 4 (Ch. 49)

• Name the four basic functions of sensory neurons.
• Name five different types of specialized neurons
  used to receive external stimuli. What is sensed
  by a nocioreceptor? What is substance P? What
  substance can be used to block the release of
  substance P? What role do prostaglandins play?
  (See pg. 1048-1049)
• What are the five basic senses in humans? Match
  one of these five with each structure listed
  below
• -olfactory -statoliths
• -pacinain corpuscle -oval window
• -rods cones -taste buds
• -lateral line system -rhodopsin
• -saccule utricle (otoliths) -incus stapes
• -sclera, cornea, retina -vitreous humor
• -tectorial, basilar, tympanic membranes

9
Hearing Equilibrium

• Mechanoreceptors are the key sensory neurons
• Invertebrates use sensory organs statocysts
• Statocysts contain statoliths
• small grains of sand (pg. 1050)
• Located at the base of antennules
• Body hairs of different stiffness lengths are
  also used- detect frequencies of sound
• Fish Aquatic amphibians use a lateral line
  system (pg. 1054)- neuromasts are the receptors
  used.

10
Key Structures of the Ear (pg. 1051-1053)
Auditory
Eustachian Tube
11
Structures in the Ear

• Two functions
• Equilibrium (Vestibular apparatus)
• Auditory (hearing)
• Structures to know for Equilibrium
• Saccule
• Utricle
• Semicircular canal (endolymph)
• Stereocilia
• Otoliths (CaCO3)
• Labyrinth
• Auditory (vestibularcochlear) nerve -cranial
  nerve

12
Equilibrium Balance

• Semicircular canal (3 fluid filled struct)
• -fluid is called Endolymph
• -detects angular acceleration
• -Utricle open into three canals located in three
  different planes
• -hair cells respond to changes in head position
• -Uticle Saccule have otoliths that trigger the
  stereocilia hairs as their positions change
• -impulse is transmitted to the Auditory nerve
• (vestibularcochlear )
• -Impulse is then sent to the brain

13
Equilibrium in the Ear
14
Otoliths in the Utricle Saccule
15
Structures for Hearing

• Sound waves are collected (funneled) into the
  ear.
• Path that sound waves take include
• -Captured by the auricle (funneled in)
• -External auditory canal
• -Tympanic membrane
• -Malleus, incus, stapes----------oval window
• -Vibrations trans. into fluid (perilymph in
  cochlea)
• -through upper vestibular canal to the apex.
• -through the lower tympanic canal to the base
  (round window)
• -Basilar membrane
• -Organ of Corti (18,000 hair cells)-floor of
  cochlea duct
• Cochlear nerve transmits impulse to the brain
• (cranial nerve)

16
Structures in the Ear
17
Sound Moving through the Ear
Pg. 1051
Perilymph
Endolymph
3 canals
18
Other Interesting Facts about the Ears (pg.
1052-1053)

• Two sound variables are detected Volume Pitch
• Volume amplitude of the wave
• more vibration of the basilar membrane greater
  bending of hair cells
• Pitch frequency of the sound wave ( waves/sec)
  Hz
• Basilar membrane is not uniform (gets wider
  towards apex)
• Each region can detect a particular vibration
  frequency
• Range of Hearing in humans 20-20,000 Hz
• Dramamine used to remedy motion sickness
• Hair cells are lost over time.

19
Evolution of the Eye

• Cup shaped structure that captured light
• Eyespots (ocelli) thought to be one of the first
  light sensitive structures in animals
• Planarian worms have these eyespots
• See pg. 1057
• Video clip from Evolution series

20
Key Structures of the Eye

• Cornea
• Iris
• Retina (rods cones photoreceptors)
• -125 million rods 6.5 million cones
• -rods (dim light) detects shapes movement of
  objects
• -Cones responsible for color vision, higher
  intesities light
• Sclera
• Aqueous humor
• Vitreous humor
• Ciliary body muscle
• Optic nerve
• Fovea (greatest density of receptor cells)

21
Pathway of Light

• Light passes through the Cornea first
• ?
• Aqueous humor
• ?
• Lens
• ?
• Vitreous humor (body)
• ?
• Retina (photoreceptor cells)
• ?
• Optic nerve

22
Rods Cones that form Retina
23
Nerve Pathway for Vision
24
The Optic Chiasm in the Eye
25
Structure of Knowledge (Ques. 1 2)

• Cornea-aqueous humor-iris-pupil-lens-vitreous
  humor-retina-(cis)rhodopsin (protein pigment in
  the membrane of rods cones)-(trans)
  rhodopsin-signal tranductionoptic nerveoptic
  chiasmvisual cortex (occipital lobe)
• Pinna (auricle)-auditory canal-tympanic
  membrane-malleus, incus,stapes,oval
  window-vestibular canal (perilymph in the
  cochlea)-apex-tympanic canal-round window
• basilar membrane (cochlear duct)hair cells
  (organ of Corti)auditory nervetemporal lobe

26
Key Structures of the Eye (pg. 1058-1062)
27
Sound Moving through the Ear
Pg. 1051
Perilymph
Endolymph
3 canals
28
Taste Smell (pg. 1056-1057)

• Chemoreceptors are present that allow for
• Taste (gustation)
• Smell (olfaction)
• Chemoreceptors located in upper portion of the
  nasal cavities
• Signal transduction allows for transmission
• Nose (over 12 million olfactory receptors)
• Each taste bud has over 100 taste receptors

29
The Tongue and Taste Buds
30
Taste

• Four general tastes
• Sweet
• Sour
• Salty
• Bitter

31
Cell Signaling with the Taste Buds
32
Taste Receptors in the Tongue
33
Signal Transduction System (pg. 211, 1056, and
1061)

• Ligand (food molecule)
• G protein
• Adenylyl cyclase
• cAMP
• Protein kinase
• Potassium channels

34
Olfactory Receptors in the Nose
35
Smell

• Seven Basic odors that can be detected
• Camphor
• Musk
• Floral
• Peppermint
• Ethereal
• Pungent
• up to 10,000 different scents have been thought
  to be detected

36
Types of Skeletons (pg. 1063-1064)

• Hydrostatic fluid under pressure
• Cnidarians (jellyfish)
• Planaria (flatworms)
• Nematodes (round worms)
• Annelids (seg. Worms-earthworms leeches)
• Exoskeleton hardened outer tissue (chitin)
• Must molt shed off the tissue for growth
• Arthropods
• Crustaceans, insects
• Endoskeleton internal bones made of cartilage or
  bone
• Chordates
• Sea urchins
• Echinderms (statfish)

37
Hierarchical Structure of Muscles

• Bone B
• Tendon T
• Fascia F
• Muscle M
• Epimysium E (covering)
• Fascicle F
• Perimysium P (covering)
• Muscle fiber (single cell) F
• Sarcolemma (cell membrane)
• Sarcoplasm (cytoplasm) S
• Sarcoplasmic Reticulum S
• Myofibrils (Two types) M
• Myosin M
• Actin A

38
Introductory Questions 4 (Ch. 49)

• Name the four basic functions of sensory neurons.
• Name five different types of specialized neurons
  used to receive external stimuli. What is sensed
  by a nocioreceptor? What is substance P? What
  substance can be used to block the release of
  substance P? What role do prostaglandins play?
  (See pg. 1048-1049)
• What are the five basic senses in humans? Match
  one of these five with each structure listed
  below
• -olfactory -statoliths
• -pacinain corpuscle -oval window
• -rods cones -taste buds
• -lateral line system -rhodopsin
• -saccule utricle (otoliths) -incus stapes
• -sclera, cornea, retina -vitreous humor
• -tectorial, basilar, tympanic membranes

39
(No Transcript)
40
Six Types of Synovioal Joints
41
Muscle Structures
42
A Muscle Cell (fiber)
43
(No Transcript)
44
Striations Light Dark Bands
45
Video Segment-Muscle Contraction

• Write 5 key statements as you watch this clip.
• Warning!!! This was a video I watched when I
  was in school. So, it is as you would say old
  school but gives accurate information and the
  music is kind of catchy.
• Enjoy!!!

46
Sarcomere Shortening (pg. 1067)
47
A Sarcomere Actin Myosin
48
Sliding-Filament Model

• Theory of muscle contraction
• Sarcomere length reduced
• Z line length becomes shorter
• Actin and myosin slide past each other (overlap
  increases)

49
Actin-Myosin Interaction (Pg. 1068-1069)

• 1- Myosin head become phosphorylated high energy
  configuration
• 2- Myosin head binds to actin and a cross
  bridge forms.
• 3- Dephosphorylation of myosin head relaxes. low
  energy configuration
• 4- Actin slides past the myosin.
• 5- Binding of a 2nd ATP releases the myosin head
  off the actin.

50
Muscle Contraction Regulation

• Relaxation tropomyosin blocks myosin binding
  sites on actin
• Contraction calcium binds to toponin complex
  tropomyosin changes shape, exposing myosin
  binding sites

51
Sliding Filaments for Muscle Contractionhttp//hi
ghered.mcgraw-hill.com/sites/0072437316/student_vi
ew0/chapter42/animations.html
52
Motor Neurons Spinal Cord
Dorsal
Ventral
53
Muscle Contraction Regulation

• Calcium (Ca)
• concentration regulated by the.
• Sarcoplasmic reticulum a specialized
  endoplasmic reticulum
• Stimulated by action potential in a motor neuron
• T (transverse) tubules travel channels in plasma
  membrane for action potential
• Ca then binds to troponin

54
Three Types of Muscle Fibers-Pg. 1072

• Slow Oxidative
• Fast Oxidative
• Fast Glycolytic
• See Table 49.1 (pg. 1072)

55
Fast Slow Muscles (Pg. 301)

• Each muscle is different on how fast it contracts
  and differ on the amount of fast and slow muscles
  present.
• Slow contracting muscles (Larger muscles)
• Red muscles (lots of myoglobin)
• Well supplied with oxygen
• Many mitochodria (aerobic respiration)
• ATP is produced at a fast rate to keep up with
  the need
• Takes longer to become fatigued
• Fast contracting muscles (smaller muscles)
• White muscles (contains less myoglobin)
• Lower oxygen supply
• Fewer mitochodria
• Sarcoplasmic reticulum is more extensive
• Ca ions and ATPases easily moved
• Examples muscles in the hand and eyes

56
Introductory Questions 4 (Ch. 49)

• Name the four basic functions of sensory neurons.
• Name five different types of specialized neurons
  used to receive external stimuli. What is sensed
  by a nocioreceptor? What is substance P? What
  substance can be used to block the release of
  substance P? What role do prostaglandins play?
  (See pg. 1048-1049)
• What are the five basic senses in humans? Match
  one of these five with each structure listed
  below
• -olfactory -statoliths
• -pacinain corpuscle -oval window
• -rods cones -taste buds
• -lateral line system -rhodopsin
• -saccule utricle (otoliths) -incus stapes
• -sclera, cornea, retina -vitreous humor
• -tectorial, basilar, tympanic membranes

57
Introductory Questions 5

• How is the optic disk different from the fovea
  structure in the eye.
• Name the fluid contained within the semicircular
  canals. How is the vestibular canal different
  from the tympanic canal? Name the fluid
  contained in these spaces.
• Name three proteins embedded in the cell membrane
  that are important for signal transduction to
  occur.
• Name three bones that are a part of the
  appendicular skeleton. Give an example of a
  hinge joint.
• What role does calcium play when a muscle
  contracts? Where is it stored?
• Define the following terms Myoglobin, Creatine
  phosphate, Motor unit, Recruitment, Tetanus
• How is isometric and isotonic contractions
  different?
• Where are smooth muscles and cardiac muscles
  located? What purpose do intercalated disks
  serve?
• Which is more costly energetically Swimming,
  running or flying? Briefly explain your response.
  (see pg. 1074)

58
The Contraction of a Muscle Sliding filament
theory (Actin/Myosin)

• http//highered.mcgraw-hill.com/sites/0072437316/s
  tudent_view0/chapter42/animations.html

59
Nerve Stimulation Causing a Muscle Contraction
60
Initiating a Muscle Contraction

• Contractions are initiated by a stimulus
• A Threshold Stimulus is first established
• Minimum strength needed to cause a contraction
• Ach is released at a certain point
• Muscles exhibit an ALL-or-NONE Response
• There are no partial contractions
• A Twitch is generated when a muscle contracts
  which lasts for only a fraction of a second.

61
A Myogram Key parts (pg. 302)
62
A Myogram

• A record of muscle contractions showing a pattern
  graphically.
• Force of Contraction (y) and time (x)
• Four key parts of a myogram
• Time of stimulation
• Latent period (time delay from stimulus to
  response)
• Very quick (0.01 sec in a frog faster in human)
• Refractory period (time delay between successive
  stimuli)
• Period of contraction
• Period of relaxation

63
Isotonic vs. Isometric (pgs.)

• Isotonic contraction occurs, muscle shortens
• Isometric contraction occurs, no movement

64
Isometric vs. Isotonic
65
Chapter 48 The Nervous System
66
Three General Function of the Nervous System
afferent
efferent
67
Functional Differences in Neurons

• Sensory neurons
• -receptor ends
• -controls impulses toward the CNS
• -referred to as afferent neurons
• Interneurons
• -association nerves
• -multipolar neurons, CNS
• Motor neurons
• -Efferent nerve fibers
• -controls impulses away from the CNS
• -common in glands and muscle tissue

68
Afferent Efferent Neurons
69
Sensory and Motor Neurons w/Spinal Cord
70
Structural Differences of Neurons

• Bipolar neurons eyes, ears, and nose (sensory)
• Unipolar neurons (ganglia outside the CNS)
• Multipolar neurons (brain spinal cord)

71
Structural Types of Neurons
72
A Typical Neuron Cell
73
Cross Section of the Axon
74
The Four Types of Neuroglial Cells

• Astocytes star shaped cells
• -found between neurons and blood vessels
• -provides support binds structures together
• -regulated glucose and potassium concentrations
• -responds to brain injury
• -nourishes nearby neurons releases growth
  factors
• Oligodendrocytes
• -arranged in rows
• -forms the myelin sheath around the axons (in
  CNS)
• -produces nerve growth factors
• Microglial Cells
• -scattered throughout the CNS
• -provides structural support
• -Phagocytic (immune protection)
• Ependymal
• -cuboidal /columnar cells
• -lines the ventricles (cavities) of the brain
• -allows free diffusion of CSF (cerebral spinal
  fluid)

Pg. 1015
75
Synaptic Junction between Neurons
76
Impulses Conducted through Neurons
77
Synaptic Junction Between Nerve Cells
78
Neuroglial Cells
79
Introductory Questions 6

• Where are neuroglial cells found in the body?
  Name the four different types and identify the
  one that provides some immune protection.
• What is the name of the small spaces that exist
  between the neurons? Can you give an example of
  a chemical that can be found in this space?
• How does the cell membrane become polarized in a
  neuron?
• What are the major ions associated with
  generating a membrane potential? Which ions are
  present in large amounts inside and outside the
  cell? What causes the inside of the cell to be
  more negative (less positive) compared with the
  outside? How much of a difference is there?
• How is the resting potential different from an
  action potential?
• What does it mean when a membrane is
  Depolarized and Repolarized?

80
A Look at the Membrane Proteins
81
Factors that Build a Polarized State

• Potassium ion move through the membrane more
  easily than sodium
• High Na on the outside low on the inside
• High K on the inside and low on the outside
• Anions are present inside the cell that cannot
  diffuse through the membrane (impermeable)
• (phosphates, sulfates, and proteins)
• Potassium ions can diffuse out faster than sodium
  ions can diffuse in
• Animated view http//bcs.whfreeman.com/thelifewir
  e/content/chp44/4401s.swf

82
The Sodium-Potassium Pump Establishing a Resting
Potential
83
An Animated View

• Voltage gated channels Proteins
• http//highered.mcgraw-hill.com/sites/0072437316/
  student_view0/chapter45/animations.html
• Choose the sodium-potassium exchange clip

84
Neural Signaling
85
Resting Potential Action Potential

• Resting Potential
• Cell reaches a charge difference of 70mV
• More Cations (Na K ) on the outside
• More anions inside and very little Na
• K is diffusing out (high to low)
• Na cant diffuse in so remains high outside
• Sodium/potassium pump increases this difference
• Action Potential
• A depolarization repolarization occurs
• Speed is one-one millionth of a second

86
Key Steps of an Action Potential
87
Neural Signaling

• Threshold potential Must reach
• The action potential involves Depolarization
  Repolarization Voltage-gated ion channels open
  close (Na K)
• 1-Resting state both channels closed Membrane
  potential (-70mV)
• 2-Threshold is reached (-50 to -55 mV) caused by
  a stimulus
• - Na channels open and sodium rushes in the
  cell
• 3-Depolarization action potential is generated
  as Na moves in cell -cell internally becomes
  more positive -40mV--20mV---etc
• A peak is reached of about 35 mV
• 4-Repolarization- begins once the peak voltage of
  35mV is reached
• -Na channels close
• -K channels open and potassium ions leave the
  cell
• -The cell internally becomes negative
• 5-Undershoot 80mV to 90mV is reached for a
  brief time
• -Both gates close
• -K channel is slow to close resting
  potential is restored

88
Generating an Action Potential
89
Self-Propagating Signaling

• The impulse travels as a wave of Depolarization
  
• The action potential Regenerates itself after
  refractory period
• Forward direction only
• Action potential speed
• Larger Axon diameter (unmyelinated) (speed
  100m/sec)
• Nodes of Ranvier (concentration of ion channels)
  saltatory conduction 150m/sec

90
Saltatory Conduction between Nodes
91
Beginning of an Action Potential
Action Potential is regenerated on another
segment of the axon.
92
An Action Potential

• Voltage gated channels Proteins
• http//highered.mcgraw-hill.com/sites/0072437316/
  student_view0/chapter45/animations.html
• Choose Action potential propagation in
  anunmyelinated axon

93
Depolarized Repolarized Membrane Activity
94
Membrane Proteins Role
Pg. 1022
95
Synaptic Cleft-Release of Neurotransmitters
96
Multiple Synapses IPSP EPSP
Summation-determine the fate of the impulse
Pg. 1023
97
Neurotransmitters (pgs. 1024-1025)

• Acetylcholine (most common)
  cholinergic skeletal muscle
• Biogenic amines (derived from amino
  acids) norepinephrine adrenergic dopamine
  serotonin
• Gases NO and CO
• Amino acids
• GABA (gamma-aminobutyric acid)
• Neuropeptides
• endorphins

98
How Drugs affect Neurotransmitter activity

• Block the binding site for the neurotransmitter
• Reduce the effect of the enzyme that breaks down
  the neurotransmitter
• Enhance the activity of the neurotransmitter
• Drugs include
• -Nicotine (mimics activity)
• -Curare (blocks the action acetylcholine)
• Inhibitory
• -Cannabis -Alcohol -Benzodiazepines
• Causes Adrenalin release
• -Amphetamines -Caffeine -Cocaine

99
Neurotransmitters affected by a Drug

• Acetylcholine Curare (?) Nicotine (?)
• Serotonin Prozac (?) Tryptophan (?)
• Norepinephrine Cocaine Antidepressants
• GABA Valium

100
Cell Signaling with the Taste Buds
101
Taste Receptors in the Tongue
102
Early Brain Development
103
Major Structures of the Brain
104
Major Structures of the Brain

• Medulla oblongata Basic bodily functions
• Pons Respiratory center
• Midbrain Visual auditory
• Thalamus All Sensory relay
• (except olfaction)
• Cerebellum Muscle coordination
• Cerebrum Intellect, memory, lang.
• Cerebral cortex (gray-outer) Voluntary muscles
• White matter (internal) Connects with
  all other parts of the brain

105
Sagittal Cross Section of the Brain
106
Close up of the Corpus Callosum
C.C.
C.P.
Thal
P.G.
4th Ventircle
107
Sagittal Section of the Head
108
Coronal Section of the Head
Cerebral Cortex
109
Lobes and Functional areas of the Brain
110
Breakdown of the PNS
111
12 Pairs of Cranial Nerves
112
Parasympathetic Sympathetic NS
113
PARASYMPATHETIC DIVISION
SYMPATHETIC DIVISION
Eye
Brain
Constrictspupil
Dilatespupil
Salivaryglands
Stimulatessalivaproduction
Inhibitssalivaproduction
Lung
Relaxesbronchi
Constrictsbronchi
Acceleratesheart
Slowsheart
Adrenalgland
Heart
Stimulatesepinephrineand norepi-nephrine
release
Liver
Spinalcord
Stomach
Stimulatesstomach,pancreas,and intestines
Stimulatesglucoserelease
Pancreas
Inhibitsstomach,pancreas,and intestines
Intestines
Bladder
Stimulatesurination
Inhibitsurination
Promoteserection ofgenitals
Promotes ejacu-lation and vaginalcontractions
Genitals
Figure 28.13
114
Areas of the Limbic System
115
Sensory Motor Areas of the Brain
116
Sagittal Cross Section of the Brain

Is this the Right or Left side of the brain?
117
The Meninges Layers in the Skull
118
A Closer Look at the Three Meninges Layers
119
Choroid Plexus Produces CSF
120
Ventricles of the Brain (lateral view)
121
Ventricles of the Brain (anterior view)
122
The Limbic System

• Affects Emotional Behavior
• Located in the Cerebrum
• Frontal temporal lobes
• Hippocampus retrieves verbal emotional
  memories
• Amygdala evaluates emotional aspects of
  experience when it perceives a threat, signals
  danger (post-traumatic stress disorders)
• Dopamine is the neurotransmitter common for this
  system
• ADD attention deficit disorders schizophrenia
  are thought to be related to dopamine levels
• Thought to be caused by excessive Dopamine

123
The Limbic System Key Structures
124
Key Structures in the Brain that Involve the
Senses
125
Electrical Activity in the Brain
126
Cerebral Cortex-Motor region w/emphasis on the
Face Hands