Introduction to the Nervous System

Front

What is the primary role of the nervous system?

Back

The nervous system is the master controlling and communicating system of the body, ensuring the body responds to stimuli and maintains homeostasis.

Front

What are the three primary functions of the nervous system?

Back

1. Sensory Input: Monitoring stimuli inside and outside the body. 2. Integration: Interpretation of sensory input and determining an appropriate response. 3. Motor Output: Activating effector organs in response to stimuli.

Front

What are the components and function of the Central Nervous System (CNS)?

Back

Components: Brain and spinal cord. Function: Integration and command center.

Front

What are the components and function of the Peripheral Nervous System (PNS)?

Back

Components: Paired spinal and cranial nerves. Function: Carries messages to and from the CNS.

Front

What are the functional divisions of the Peripheral Nervous System (PNS)?

Back

1. Sensory (Afferent) Division: Somatic (from skin, skeletal muscles, and joints to the brain) and Visceral (from visceral organs to the brain). 2. Motor (Efferent) Division: Somatic Nervous System (voluntary control of skeletal muscles) and Autonomic Nervous System (involuntary control of smooth muscle, cardiac muscle, and glands).

Front

What are the types of neurons based on structure?

Back

1. Multipolar Neurons: Three or more processes, most common in the CNS. 2. Bipolar Neurons: Two processes, rare, found in special sense organs. 3. Pseudounipolar (Unipolar) Neurons: One process, found primarily in the PNS.

Front

What are the types of neuroglia in the CNS and their functions?

Back

1. Astrocytes: Support neurons and regulate the extracellular environment. 2. Microglial Cells: Monitor neuronal health and act as macrophages. 3. Ependymal Cells: Line cavities filled with cerebrospinal fluid and help circulate it. 4. Oligodendrocytes: Produce myelin sheaths around CNS nerve fibers.

Front

What are the types of neuroglia in the PNS and their functions?

Back

1. Schwann Cells: Form myelin sheaths around thicker nerve fibers. 2. Satellite Cells: Surround neuron cell bodies and have functions similar to astrocytes in the CNS.

Front

What is the function of myelin sheaths?

Back

Myelin sheaths protect axons, electrically insulate fibers, and increase the speed of nerve impulse transmission. Formed by Schwann cells in the PNS and oligodendrocytes in the CNS.

Front

What is the resting membrane potential (RMP)?

Back

The polarized state at -70mV due to ionic differences and membrane permeability.