Physiology Chapter 8 - Nervous System PDF

**[Chapter 8]** 1. Map the organization of the nervous system in detail. A diagram of a human brain Description automatically generated - **Central Nervous System (CNS):** Brain and spinal cord; processes information and coordinates activity. - **Peripheral Nervous System (PNS):**...

**[Chapter 8]** 1. Map the organization of the nervous system in detail. A diagram of a human brain Description automatically generated - **Central Nervous System (CNS):** Brain and spinal cord; processes information and coordinates activity. - **Peripheral Nervous System (PNS):** - **Afferent Division:** Sensory input from receptors to the CNS. - **Efferent Division:** Motor output from the CNS to effectors, further divided into: - **Somatic Nervous System (SNS):** Controls voluntary movements (skeletal muscles). \*\*\* Usually voluntary, but not always - **Autonomic Nervous System (ANS):** Controls involuntary activities (smooth muscle, cardiac muscle, glands), divided into: - **Sympathetic Division:** \"Fight or flight\" response. - **Parasympathetic Division:** \"Rest and digest\" response. - **Enteric Nervous System (ENS):** Network of neurons in the gastrointestinal tract. 2. Name the types and functions of glial cells.  - **In the CNS:** - **Astrocytes:** Maintain the blood-brain barrier, provide structural support, and regulate ion and neurotransmitter concentrations. - **Oligodendrocytes:** Myelinate CNS axons to increase signal transmission speed. - **Microglia:** Act as immune cells; remove debris and pathogens. - **Ependymal Cells:** One source of neural stem cells - **In the PNS:** - **Schwann Cells:** Myelinate PNS axons and aid in repair after injury. - **Satellite Cells:** Surround neuronal cell bodies in ganglia, providing support and nutrient exchange. 3. Compare and contrast graded potentials and action potentials. A table of periodic table Description automatically generated  A diagram of potential Description automatically generated 4. Explain the changes in ion permeability and ion flow that take place during an action potential. (Must know specifics with activation and inactivation gates)  A diagram of a voltage gated number Description automatically generated 5. Describe and compare absolute and relative refractory periods.  - **Absolute Refractory Period:** - No new action potential can be initiated. - Na⁺ channels are inactivated, preventing depolarization. - **Relative Refractory Period:** - A new action potential can occur with a stronger-than-normal stimulus. - Some Na⁺ channels are reset, but K⁺ channels remain open. 6. Describe the role of the following in synaptic communication: ionotropic and metabotropic receptors, neurotransmitters and neuromodulators, fast and slow synaptic potentials, excitatory and inhibitory postsynaptic potentials. A diagram of a cell membrane Description automatically generated  A diagram of synapse and neuronal neurons Description automatically generated 7. Explain the mechanism of long-term potentiation mediated by AMPA and NMDA receptors.  - **LTP Process:** - **Initial Signal:** Glutamate is the key, it binds to AMPA and NMDA receptors. - **AMPA Activation:** Na⁺ influx through AMPA receptors causes depolarization. - **NMDA Activation:** Depolarization removes Mg²⁺ block from NMDA receptors, allowing Ca²⁺ influx. - **Calcium Role:** Ca²⁺ activates intracellular signaling pathways, leading to: - Activation of second messenger pathways - Paracrine release from postsynaptic cell which enhances glutamate release - **Result:** Enhanced synaptic transmission, a cellular basis for learning and memory.