Perceptions & Coordination

• Perception is the process of receiving stimuli or data and consciously organizing and translating them into meaningful information
• Coordination is the combination of body activities that result in intended actions
• Organs Systems involved in perception: Special Senses, Nervous System, Muscular System, Skeletal System
• Special senses with specialized organs devoted to them:

  • Vision (the eye)
  • Hearing and balance (the ear, which includes the auditory system and vestibular system)
  • Smell (the nose)
  • Taste (the tongue)
• Physical information from the world (light) includes:

  • Hue ("color"): wavelength
  • Saturation: purity of the light wave
  • Brightness: intensity of the electromagnetic radiation
• The eye:

  • Specialized sense organ
  • Specialized neural tissue (retina)
  • Specialized sensory receptors (rods, cones)
  • Sensory transduction: light - neural activity
• The ear:

  • Organ of hearing and equilibrium
  • Detects and analyzes noises by transduction (conversion of sound waves into electrochemical impulses)
  • Maintains the sense of balance (equilibrium)
• The human nervous system controls and integrates many activities of the body and has two divisions:

  • Central Nervous System (CNS) including the Brain, Spinal Cord, CN I & II
  • Peripheral Nervous System (PNS) including CN III to XII, Spinal Nerves, Peripheral components of ANS
• Cells of the Nervous System:

  • Neurons with basic parts: Cell body, Axon, Dendrite
  • Neurons with types: Multipolar, Bipolar, Unipolar
  • Glial Cells (Neuroglia) including Astrocytes, Ependymal cells, Microglia, Oligodendrocytes, Schwann cells
• Organization of Nervous Tissue:

  • Non-myelinated sheath in Brain (Cortex) and PNS (Ganglion)
  • Myelinated sheath in CNS (conduction pathways, nerve tracts)
• Action Potential includes:

  • Resting Membrane Potential
  • Depolarization
  • Repolarization
• Intracranial volume components:

  • Brain
  • CSF
  • Blood and Blood vessel
  • Dilatation with high pCO2
  • Constriction with low pCO2
• Types of Muscle Tissue:

  • Skeletal
  • Cardiac
  • Smooth
• Parts of a Muscle:

  • Origin
  • Belly
  • Insertion
• The Myofibrils and Myofilament:

  • Thin Filament
  • Thick Filament
• The Neuromuscular Junction
• Muscle Contraction steps:

  1. Action potential arriving at the presynaptic terminal causes synaptic vesicles to move and bind with cell membrane.

  2. Synaptic vesicle releases acetylcholine (ACh) into the synaptic cleft by exocytosis.

  3. ACh diffuses across the synaptic cleft.

  4. ACh binds to Ach-Receptor sites on Na+ channels in the postsynaptic (muscle) cell membrane.

  5. Combination of ACh with its receptor sites opens Na+ channels and causes an increase in the permeability of the muscle cell membrane to Na+.
• Divisions of the Skeletal System:

  • Axial
  • Appendicular
  • Classification of Bones: Long, Short, Flat, Irregular
• Haversian System and Bone Cell Types
• Names of Bones