Neurons/Divisions of the Nervous System Quiz Flashcards
What is a dendrite?
Usually numerous and receive impulses from sensory receptors or other neurons passing the impulse to the body cell.
What is an axon?
Usually singular; carry impulses away from cell body to other neurons or effectors.
What is the cell body/soma?
Contains the organelles of the neuron, including the nucleus therefore controlling cellular activities and undergoing cellular processes.
What is the myelin sheath?
Layer of a fatty tissue that insulates the axon and helps speed up message transmission.
What is a schwann cell?
A type of glial cell which produces the myelin sheath.
What are the Nodes of Ranvier?
Gaps in the myelin which allow the impulse to jump from node to node thereby speeding up the transmission of the message.
What is the end brush?
The branches off of the axon, allows information to be dispersed to several areas.
What is the terminal button?
Releases chemicals into the space between neurons when the neuron is fired to pass on the impulse.
Define nervous system.
Receives internal and external stimuli. Coordinates and interprets all stimuli to allow a response to occur.
Define central nervous system (CNS).
Consists of the brain and spinal cord.
Define what the brain does in the nervous system.
Contains 100 billion neurons. Covered by meninges. Main coordinator. Analyzes sensory information.
Define what the spinal cord does in the nervous system.
Relays information to and from the brain to the rest of the body. Consists of grey and white matter.
Define peripheral nervous system (PNS).
Contains only nerves, connects brain and spinal cord to the rest of the body. Most sensory input remains below the level of conscious awareness.
Define somatic nerves.
Nerves leading to the skeletal muscles, contain sensory and motor neurons, control reflexes.
Define motor nerves.
Creates pathways that carry signals to the muscles and glands.
