Chapter 8 Flashcards
(40 cards)
2) What part of the cell contains the nucleus and is the site of NT synthesis?
2) Cell Body.
3) What part of the cell brings signals toward the cell body?
3) Dendrites.
4) What part of the cell sends signals away from the cell body?
4) Axon.
5) The sheath that forms an electrical barrier around the axon is composed of?
5) Myelin.
6) Sensory nerves are also known as?
6) Afferent Neuron.
7) Motor nerves are also known as?
7) Efferent Neurons.
8) Name and describe both types of afferent neurons?
8) Psuedounipolar:
Single axon, dendrite has fused with axon and action potential may bypass.
Bipolar:
One axon and one dendrite roughly of equal size with cell body.
9) Interneurons are found in the ?
9) In the neurons of the CNS.
10) The term anaxonic means?
10) No apparent axon.
11) What is the term for a narrow gap between an axon and its target and its target cell?
11) Synapse.
- What is the most common neurotransmitter used between neurons?
12) Acetylcholine (ACH)
13) What membrane process releases neurotransmitters into the synapse during an action potential?
13) Exocytosis
14) The arrival of an action potential at a target cell might cause what three things to happen?
14) Continue action potential, muscle contraction, or gland to secrete.
15) Which of the following is true of neuroglial cells?
15) Doesn’t rely on action potential of neurons.
Supports and nourish neuron cell bodies in CNS.
16) The myelin sheath in the CNS is formed by __ cells?
16) Oligodendrocytes
17) The myelin sheath in the PNS is formed by __ cells?
17) Schwann cells
18) What type of cells for barriers (like the blood brain barrier) between fluid filled compartments?
18) Ependymal cells.
19) What glial cells have scavenger, defense, and metabolic assistance functions?
19) Microglia cells.
20) Which of the following is true of graded potentials?
20) Vary in strength.
Lose strength over distance.
Are slower than action potential.
21) The area at which an action potential will initiate if the graded potential is strong enough is called the __ zone?
21) Trigger Zone.
22) What term means that a graded potential is too weak to start an action potential?
22) Sub Threshold.
23) Which of the following is true of a polarized neuron?
23) Na/K pumps have readied membrane ap.
High levels of Na+ outside neuron low inside.
Low levels of K+ outside neuron higher outside.
Inhibition arrival of graded potential with sufficient strength to stimulate AP Depolarization **
24) The arrival of a graded potential with sufficient strength causes what event to happen in a polarized cell?
24) Initiation of action potential.
25) What step in an action is characterized by the sodium gates opening and sodium rapidly diffusing into the cell?
25) Depolarization.
