Chapter 12: nervous tissues; properties of neurons

Question 1

What cells are in charge of the communicative role of the nervous system?

Answer 1

nerve cells/neurons

Question 2

What are the 3 fundamental physiological properties that enable them to communicate with other cells

Answer 2

Excitability - they respond to environmental changes (stimuli). Neurons exhibit this property to the highest degree

conductivity - neurons respond to stimuli by producing electrical signals that are quickly conducted to other cells at distant locations

secretion - when the signal reaches the end of a nerve fiber, the neuron secretes a neurotransmitter that crosses the gap and stimulates the next cell

Question 3

What are sensory (afferent) neurons

Answer 3

specialized neurons that detect stimuli such as light, heat, pressure, and chemicals and transmit information about them to the CNS

they conduct signals toward the CNS

Question 4

Whats the difference in sensory neurons for pain and smell vs taste and hearing?

Answer 4

for pain and smell the cells are themselves neurons

for taste and hearing the receptor is a separate cell that communicates directly with a sensory neuron

Question 5

Interneurons

Answer 5

lie entirely within the CNS. They They receive signals from many other neurons and carry out integrative function of the nervous system. They, process, store, and retrieve information and make decisions that determine how the body responds to stimuli.

Question 6

What percentage of neurons are interneurons?

Answer 6

90%

Question 7

Motor (efferent) neurons

Answer 7

send signals predominantly to muscle and gland cells, the effectors. They are called motor neurons because most of them lead to muscle cells, and efferent neurons to signify signals conduction away from the CNS