The Human Nervous System Quiz

Parts of the Nervous System

• Comprised of two main parts: Central Nervous System (CNS) and Peripheral Nervous System (PNS).

Central Nervous System

• Made up of the brain and spinal cord, acting as the control center for processing information.

Peripheral Nervous System

• Consists of nerves that communicate impulses between the CNS and the rest of the body.

Neurons

• Functional subunit of the nervous system is the neuron, or nerve cell.
• Three types of neurons:
  • Sensory Neurons: Transmit impulses from sensory receptors to the CNS.
  • Motor Neurons: Convey impulses away from the CNS to effectors (muscles and glands).
  • Interneurons: Facilitate communication within the CNS.

Neuron Structure

• The cell body of a neuron receives impulses from dendrites, containing the nucleus that governs neuron activities and produces neurotransmitters.
• Myelin sheath serves to insulate neurons and enhance the speed of electrical signal transmission.

Synapse

• The synapse is the region where two neurons are closely aligned.
• Synaptic cleft refers to the physical space that exists between two neurons, crucial for neurotransmitter transfer.

Neurotransmitters

• Chemical messengers released into the synapse to facilitate signal transmission between neurons.

Brain Functions

• The medulla oblongata governs involuntary actions such as breathing and heart rate.
• The hypothalamus plays a key role in maintaining homeostasis within the body.

Stimuli and Responses

• A stimulus is defined as any environmental change that elicits a reaction.
• Reflex actions are involuntary responses to stimuli, critical for protecting the body from harmful conditions.

Examples of Reflex Actions

• Common reflex actions include:
  • Eye blinking
  • Adjusting pupil size
  • Quick withdrawal of a hand from a hot surface.

Reflex Arc

• The reflex arc describes the specific nerve pathway utilized when responding to a stimulus, illustrating the efficiency of the nervous system's response mechanisms.

Nervous System Disorders

• Disorders of the nervous system can have varied symptoms, causes, and treatments; specific examples include an unnamed condition needing detailed attributes.