A&P II Module 1

• What is the difference between anatomy and physiology?

  Anatomy focuses on the structure of the body. Physiology looks at how the body parts function together. The physiology of the body depends on the anatomy of the body.
• The function of the nervous system is to integrate and control the other body systems. Explain how the nervous system does this.

  The nervous system receives and processes information and sends out signals to the muscles and glands to elicit an appropriate response. In this way, the nervous system integrates and controls the other systems of the body.
• List the 2 parts of the nervous system.

  CNS and PNS (central nervous system and peripheral nervous system)
• How are the parts of the central nervous system protected?

  Theskullprotects the brain and thevertebraeprotect the spinal cord.
• Collections of cell bodies inside the central nervous system are called


  _____, and the collection of nerve axons in the central nervous system are called_____nuclei, tractsSee an expert-written answer!We have an expert-written solution to this problem!
• What is included in the peripheral nervous system?

  The PNS includes the cranial nerves and the spinal nerves
• Collections of cell bodies inside the peripheral nervous system are called


  _____, and the collection of nerve axons in the peripheral nervous system are called_____ganglia, nervesSee an expert-written answer!We have an expert-written solution to this problem!
• What are the 2 divisions of the peripheral nervous system?

  Afferent, efferent
• Describe the movement of nerve impulses in the peripheral nervous system.

  The peripheral nervous system receives impulses from the sensory organs via the afferent division and then relays signals or impulses from the central nervous system to muscles and glands via the motor or efferent division
• What are the 2 divisions of the efferent division of the peripheral nervous system?

  Somatic system and the autonomic system
• What is controlled by the somatic and autonomic nervous systems?

  The somatic system controls the movements of skeletal muscles, skin, and joints. The autonomic system nerves control the glands and smooth muscles of the internal organs
• What are the 2 divisions of the autonomic nervous system?

  sympathetic and parasympathetic nervous systems
• What is the function of the sympathetic nervous system?

  The sympathetic nervous system activates and prepares the body for vigorous muscular activity, stress, and emergencies
• What is the function of the parasympathetic nervous system?

  The parasympathetic nervous system generally operates during normal situations, permits digestion, and conserves energy
• List 3 unusual characteristics of neurons

  Neurons do not undergo mitosis (cell division), require enormous amounts of fuel being able to survive just minutes without oxygen and can last an entire human lifetime.
• Describe the structure and function of the neuron cell body

  Synthesizes all nerve cell products, consists of a large nucleus with surrounding cytoplasm containing the normal organelles
• Describe the structure and function of the dendrite


  Numerous short extensions that emanate from the cell body which receive information from other neurons conducting those nerve impulses toward the cell body.
• Describe the axon, including the number in each neuron, function, structure and organelles

  Conducts nerve impulses away from the cell body to its axon terminals where it is emitted across a synapse to the dendrite of another neuron. Axons are composed of cells like the cell body but lack rough endoplasmic reticulum
• Describe the function and site of synthesis and storage of neurotransmitters


  One of the main functions of the cell body is to manufacture neurotransmitters, which are chemicals stored in secretory vesicles at the end of axon terminals.When neurotransmitters are released by the axon terminal vesicles, they carry the transmission of the nerve impulse from one neuron to another
• What is a synapse?

  A synapse is a gap between two neurons
• A post-synaptic neuron is a neuron that is found ____ the synapse

  After
• ______neurons have three or more extensions from the cell body and have one axon and many dendrites

  Multipolar
• _________ neurons have a central cell body with two extensions

  Bipolar
• _____ neurons have one extension off the cell body which branches into two: one central process running to the CNS and another peripheral process running to the sensory receptorUnipolar (pseudounipolar)
• ______ neurons are unipolar and function to carry information from the peripheral to the central nervous systemSensory
• These types of neurons are also called association neurons


  Interneurons
• _____ neurons send messages from the central nervous system to the peripheral

  Motor
• What is the function of neuroglical cells?

  Neuroglial cells are support cells, helping to support neurons to enable them to thrive in their needed environment
• What are the peripheral nervous system neuroglical cell types?

  Schwann cells; satellite cells
• True or False: Axons cannot regenerate in the peripheral nervous system.

  False
• True or False: Myelin sheath is continuous and has no gaps

  False
• List the four types of support neuroglical cells in the central system and a function of each

  Ependymal cells circulate cerebrospinal fluid and allow fluid exchange between brain, spinal cord and cerebrospinal fluid (CSF). Oligodendrocytes act as the insulation for central nervous system axons. Astrocytes control chemical environment of neurons by wrapping around the blood capillaries, forming the blood brain barrier. Microglial cells protect the CNS by scavenging dead cells and infectious microorganisms
• What is the technical term used to describe a nerve impulse and what causes the impulse?

  A nerve impulse is called an action potential and is caused by the movement of unequally distributed ions on either side of an axon's plasma membrane.
• An axon's membrane is polarized with a resting potential of -70 mV. Explain what this means and what maintains this resting potential.

  The axon plasma membrane is polarized, meaning that one side has a different charge than the other side. This difference called a resting potential means that the charge on the inside of the axon's cell membrane is 70 millivolts less than the outside of the membrane. A sodium- potassium pump using active transport carries ions across the plasma membrane and because three Na+ ions are pumped out as two K+ ions are pumped in a relative positive charge develops and is maintained on the outside of the membrane
• What are the four steps of an action potential in order?

  Resting Potential, Depolarization, Repolarization, Afterpolarization (hyperpolarization)
• Describe what happens to the charges on the axon cell membrane during

  depolarizationand what causes this to happen.Sodium gates open and sodium rushes into the axon and the inside becomes more positive than the outside causing the membrane potential to become more positive
• Describe what happens to the charges on the axon cell membrane during

  repolarizationand what causes this to happen.The sodium gates close and potassium gates open allowing potassium to rush out of the axon. This returns a negative charge to the inside of the axon re-establishing the negative potential
• Describe what happens during afterpolarization.

  The potassium gates that open during repolarization are slow to close and there is an afterpolarization undershoot of the potential.
• What causes the difference in intensity of a sensation?

  Due to the number of neurons stimulated and the frequency with which they are stimulated
• True or False: An impulse from a neuron moves in both directions.

  False