8th Grade BYOD lesson. Nervous System 1

The structures of the PNS are referred to as ganglia and nerves, which can be seen as distinct structures.

Hey there everyone. Today we are going to cover general structure of the nervous system. If you have any question or comments email me at ildar.yakhin@litsey7.com or just go and see me. Enjoy the lesson!

The Nervous System. General Structure

Learning Outcomes

Content: to Identify the anatomical and functional divisions of the nervous system; to relate the functional and structural differences between grey matter and white matter structures of the nervous system to the structure of neurons.

Language: to be able to list the basic functions of the nervous system.

1 (team work). Explain this text to your group after reading the paragraph. Check if you understand whole!

The nervous system can be separated into divisions on the basis of anatomy and physiology. The anatomical divisions are the central nervous system (CNS) and peripheral nervous systems (PNS). The CNS is the brain and spinal cord. The PNS is everything else. The brain is contained within the skull, and the spinal cord is contained within the vertebral column. The peripheral nervous system is named peripheral because it is on the periphery—meaning beyond the brain and spinal cord. Functionally, the nervous system can be divided into those regions that are responsible for sensation, those that are responsible for integration, and those that are responsible for making responses. All of these functional areas are found in both the central and peripheral parts.

Nervous tissue presents in both the CNS and PNS and contains two basic types of cells: neurons and glial cells. A glial cell provides basic structure of tissue that supports the neurons and their activities. A neuron is more functionally important in terms of the communicative function of the nervous system. To describe the functional divisions of the nervous system, it is important to understand the structure of a neuron. Neurons are cells and therefore have a cell body but they also have extensions of the cell; each extension is generally referred to as a process. There is one important process that every neuron has called an axon, which is the fiber that connects a neuron with its target. Another type of process that branches off from the cell body is the dendrite. Dendrites are responsible for receiving most of the input from other neurons. Looking at nervous tissue, there are regions that predominantly contain cell bodies and regions that are largely composed of just axons. These two regions within nervous system structures are often referred to as grey matter (the regions with many cell bodies and dendrites) or white matter (the regions with many axons). The white matter is white because axons are insulated by a fat-rich substance called myelin.

Multipolar Neuron
2 (individual work). Fill in the blanks by using text above.

Structure	Function
glial cell
	communicative function of the nervous system
white matter
	process that branches off from the cell body

3 (individual work). Fill in the blanks by using words and phrases below.

spinal cord
physiology
brain
PNS
CNS
sensation
generating responses
anatomy
grey matter

The nervous system can be separated into divisions on the basis of (A)___ and (B)___. The CNS is the (C)___ and (D)___. The (E)___ is everything else. Functionally, the nervous system can be divided into those regions that are responsible for (F)___, those that are responsible for integration, and those that are responsible for (G)___. All of these functional areas are found in both the central and peripheral anatomy.

Nervous tissue can also be described as (H)___ and white matter on the basis of its appearance in tissue. These descriptions are more often used in the (I)___.

HW (individual work). Write summary after watching the video.