nervous system

Question 1

properties of nervous system

Answer 1

All cells are naturally charged

Nervous tissue - Uses electrical charge for rapid communication

Question 2

functions of the nervous system

Answer 2

• Receive sensory input
- Monitor changes inside and outside the body
• Integration (Most complex)
- Processes and interprets sensory input
• Motor output
- Causes a response by activating effector organs (muscle or gland)

Question 3

describe the regional division of the nervous system.

Answer 3

central nervous system-brain and spinal cord, transmits to and from the brain.

peripheral nervous system- spinal nerves and ganglia, carry signals to and from the spinal cord.

Question 4

describe the functional division of the central nervous system.

Answer 4

Afferent/sensory-carries signals to the brain, somatic is outer tube like skin, skeleton, visceral is the inner organs
Efferent/motor- carries signals from brain to the effectors. the somatic ns here is voluntary conducts to skeletal muscles, the visceral autonomic nervous system is involuntary and conducts to the cardiac, smooth muscles and glands

Question 5

describe the autonomic nervous system function and divisions.

Answer 5

involuntary conductor of the cardiac, smooth muscles and glands. It is divided into the sympathetic and parasympathetic ns.
sypm- is flight or flight
para- rest and digest.

Question 6

describe the function and general characteristics of neurons

Answer 6

function- rapid transmission and intergration of signals
they are specialized for rapid electric charge.
they live over 100 years, they do not divide, exceptionally high metabolic rate.
they have a cell body and a ‘process.

Question 7

describe the structure and signal route of a typical multipolar neuron.

Answer 7

cell body (soma), usually numerous dendrites (recieve the signal and sends it to the cell body), axon recieves the signal from the axon hillock at cell body, the signal then transmitted down the axon terminal, wrapped in a mylin sheath to the axon terminals. At the synapse (the communication spot between neurons)

Question 8

what is the definition and function of a synapse?

Answer 8

site of neuron-neuron communication.

most are chemical using neurotransmitter to cross the synaptic cleft. some are electric using gap junctions.

Question 9

define the types of neurons based on their functional classifications.

Answer 9

sensory neurons (afferent)- they transmit impulses toward the CNS from sensory receptors in the PNS. 
motor neurons (efferent)- they transmit impulses away from the CNS toward the effector muscles or glands.
Interneurons (association neurons)- multipolar that link everybody up, specialized diverse size and branching patterns. confined entirely to the CSN.

Question 10

what are the function and properties of neuroglia (glia)?

Answer 10

the ‘other component of nervous tissue
does not send nervous signals, rather it supports neurons.
outnumber neurons!
continue dividing through life. (most brain cancers are glial cell tumors)

Question 11

what are the types and functions of neuroglia?

Answer 11

there are 4 types in the CNS

• oligodendrocytes (myelinate/ coil around axons)
• microglia (immune cells/ macrophages et. of the CNS)
• astrocytes (most abundant, cover neurons in the cns and control environment there like the flow of ions/neurotrans in capillaries)
• ependymal (epithelium type of cell, lines the brain and spinal cord cavity, controls molecules movement across the surface)

2 in the PNS.

• Shwann cells (like oligodendrocytes, myelinate axons in the PNS, nerve regeneration)
• Satellite cells (similar to astrocytes {manage flow} , associated with cell bodies in the PNS only)

Question 12

myelin

Answer 12

is a lipoprotein covering, insulates axon for speed and protection. Coils around to make the tight seal.

Question 13

a disease breaks down the myelin IN THE BRAIN. suppose that the debris cleaned up and the structure is regenerated. which cells preform this function?

Answer 13

microglia

Question 14

Describe the gross anatomy of a nerve.

Answer 14

group of axons traveling together within a nerve.
around the entire nerve is surrounded by the entire nerve is the outer layer.
fasicle is the bundle of muscles.

Question 15

describe the difference between a nerve and a neuron.

Answer 15

nerve is an entire structure, complex system within the nervous system
neuron is a cell

Question 16

a nerve…

Answer 16

contains the axons of many neurons. axons are also called nerve fibers, each travel from cell body to axon terminals
most nerves, the only exception being cranial nerves, carry signals in both directions-because nerves carry neurons oriented in both directions with a nerve unit.

Question 17

ganglion

Answer 17

collection of nerve cell bodies in the PNS

Question 18

in the CNS, describe the white and gray matter.

Answer 18

white matter is myeilinated axons, oligodendrocytes.

grey matter is ‘everything else: unmyelinated axons, dendrites, cell bodies. (think of the striations of sarcomere)

Question 19

tract in the ns.

Answer 19

collection of axons traveling together INSIDE THE CNS.

Question 20

nucleus in the cns.

Answer 20

collection of cell bodies INSIDE THE CNS.

this is grey matter.