- be able to identify nervous tissue
- know that nervous tissue is composed of neurons and glial cells
- know that neurons are cells responsible for rapid internal communication and integration of information
- know that glial cells are the support cells of the nervous system
- know where nervous tissue is located within the body
This packet is designed to give you a brief introduction into nervous tissue from a histology perspective. There will be a more comprehensive and in-depth packet about nervous tissue and how it applies to the functionality of the nervous system later on.
There isn't a whole lot to write about right now since you have a whole chapter devoted to this topic. Basically all I need you to know about nervous tissue right now is that it's comprised of neurons and glial cells; glial cells support neurons. Also know that nervous tissue is found in the brain, the spinal cord and peripheral nerves. We basically use nervous tissue for rapid internal communication about the state of our internal environment and any changes to our homeostasis that may be occurring.
One more important fact about nervous tissue you need to start thinking about is that it's one of the exictable tissues of the body, muscle being the other. Another word for excitable is irritable. This means that nerves can become irritated by changes in their environment (stimuli). These irritations or stimuli will wind up stimulating a nerve to send an impulse (action potential). These impulses are how we are able to communicate rapidly about changes in our environment.
Source: The mind of Aaron
This is an overview of nervous tissue from a histology perspective. This video will help you identify nervous tissue under the microscope and give you a foot in the door about its functions.
Source: Self made with images from Marieb and http://www.udel.edu/biology/Wags/histopage/colorpage/colorpage.htm
In this slideshow you will see some images of neurons and glial cells. Notice that neurons have large cell bodies (soma) that are stellate (star shaped). It's difficult to see but if you look closely you may be able to see the axon projecting off from the cell soma of the neurons. Also, you should be paying attention to the various morphological differences between neurons and glial cells.
Source: Self made with images from http://www.udel.edu/biology/Wags/histopage/colorpage/colorpage.htm