Group+5+page

Group page for saving stuff, group 5 period 3. Kelsey, Jim, Dave and Gavin


 * What is a nerve net?**

A nerve net is a web-like system of neurons that allows the body to communicate easily.
 * Compare and contrast the central and peripheral nervous systems.**

Central:
 * Includes the brain and spinal cord
 * Controls involintary movement
 * Protected by blood brain barrier

Peripheral:
 * Includes sensory motor pathways, somatic/autonomic nervous system and the parasympathetic/sympathetic division
 * Controls volintary movement
 * Regulates blood pressure, thrirst and body temperature.


 * How does the organization of the nervous system of a compare with the organization of the nervous system of a _?**

Hydra has a full nerve net while the insect has a ventral nerve cord and segmental ganglia along with a brain.
 * a. Hydra and insect**

Again, hydra has a full nerve net. The flat worm has two nerve cords connected by many transverse nerves as well as a brain and eyespots.
 * b. Hydra and flatworm**
 * c. Leech and salamander**

Leeches a brain connected to a ventral nerve cord which has segmental ganglion.

A salamander has the largest brain of these five, which is connected to a dorsal nerve cord with sensory ganglion.

a. Sensory neurons They transmit external stimuli to nervous system. b. Interneurons They integreate and interupt sensory input. c. Motor neurons They output the information to muscle or cells that do external work. d. Effector Cells Cells that actually do work (such as mucle cells).
 * What are the functions of the following:**


 * Why is it advantageous for the reflex response to circumvent instructions from the brain? Why might it be disadvantageous?**

It allows for faster reaction time in emergencies.


 * Neuron:**

They support and hold together the neural net, acting like a glue.
 * Why are glial cells important?**