Introduction to Nervous Tissue

These flashcards cover the key concepts related to the structure and function of the nervous system, neurons, and neuroglia as discussed in Chapter 11.

What are the three main divisions of the nervous system?

Central Nervous System (CNS), Peripheral Nervous System (PNS), Enteric Nervous System (ENS)

What is the primary role of the Central Nervous System (CNS)?

Integrates, processes, and coordinates sensory and motor commands.

What does the Peripheral Nervous System (PNS) consist of?

All nervous tissue outside the CNS, excluding the ENS.

What is the function of sensory (afferent) division of the PNS?

Brings information to the CNS from receptors in peripheral tissues and organs.

What types of muscles are controlled by the Autonomic Nervous System (ANS)?

Smooth muscle, cardiac muscle, glands, and adipose tissue.

What are the general functions of the nervous system?

Detect changes in the environment, process information in the CNS, and send motor commands to effectors.

What is the structure and function of a neuron?

Neurons have dendrites (receive stimuli), a cell body (contains the nucleus), and an axon (carries information toward other cells).

What are the major functional classes of neurons?

Sensory neurons, interneurons, and motor neurons.

What are the four types of glial cells in the CNS?

Ependymal cells, microglia, astrocytes, and oligodendrocytes.

What is the primary role of astrocytes?

Maintain the blood-brain barrier, provide structural support, regulate ion and nutrient concentrations, and recycle neurotransmitters.

How do oligodendrocytes function in the CNS?

Provide a framework by stabilizing axons and producing myelin which speeds up nerve impulse transmission.

What is the difference between myelinated and unmyelinated axons?

Myelinated axons have a myelin sheath which speeds up transmission and appear white, while unmyelinated axons lack myelin and appear gray.

What happens during nerve regeneration in the PNS?

Schwann cells assist in repairing damaged axons through a specific regeneration process.

Describe the difference in axon repair between the CNS and PNS.

Regeneration is limited in the CNS due to astrocytes producing scar tissue and blocking axon growth.