Coordination and Regulation- Nervous Systems

Question 1

3 General Roles of Nervous System

Answer 1

1. collects info from internal or external environment using sensory neurons
2. Process and integrate info- evaluates based on past experiance or genetics
3. Transmits info- coordinates/ regulates effector organ/ cells

Question 2

What are Neurons

Answer 2

Generate bioelectric signals which are used to transmit info to other cells

Question 3

What are Glia

Answer 3

“support cells””- assist neuronal signalling, produce cerebrospinal fluid, maintain environment around neurons

Question 4

Neuron

Answer 4

individual cells

Question 5

nerve

Answer 5

a bundle of axons

Question 6

axons

Answer 6

nerve fiber

Question 7

synapses

Answer 7

connection between axon terminal and effector cell

Question 8

effector

Answer 8

can be a neuron, muscle cell, any other cell

Question 9

bioelectricity

Answer 9

happens all around membrane

Question 10

potential

Answer 10

difference in electrical charged between regions- measured in volts or millivolts

Question 11

current

Answer 11

flow of electrical charge between regions- opposites attract, likes repel

Question 12

membrane potential

Answer 12

unequal charge distribution across a cell membrane

Question 13

electrical potentials

Answer 13

used to initiate an AP in axon hillock and used to conduct AP along axon -current (ions) travel along surface of membrane, small, can depolarize or hyperpolarize, can only travel short distance

Question 14

Depolarization

Answer 14

more +ve inside of cell, makes cell less negative

Question 15

Hyperpolarization

Answer 15

more -ve inside cell, makes cell more negative

Question 16

Resting Membrane Potential

Answer 16

measured when neuron is inactive -about -70mV in neurons and muscle cells

Question 17

Electrotonic Potential

Answer 17

passive change in membrane potential -amplitude decreases with distance from point of initiation

Question 18

Action Potential

Answer 18

initiated at axon hillock region, are all or nothing but short

Question 19

Unmyelinated axon

Answer 19

reduce threshold at axon hillock, concentration of Na+v channels and spreads along membrane toward terminals
-axon diameter determines speed of conduction (large=faster)

Question 20

Myelinated axon

Answer 20

surrounded by myelin insulation preventing ions from crossing membrane

Question 21

Electrical Synapses

Answer 21

gap junctions directly connect to cytoplasm of each cell, ions flow between cells, rapid flow of current

Question 22

Chemical Synapses

Answer 22

pre and postsynaptic neurons seperated by synaptic cells

Question 23

Main difference between chemical synapse and electrical synapse

Answer 23

neurotransmitter binds to postsynaptic receptors, channels open, depolarization (excitatory) or hyperpolarization (inhibitory)

Question 24

Neurotransmitters

Answer 24

stimulates skeletal muscle contraction

Question 25

Ionotropic Receptors

Answer 25

ligand gated ion channels, post synaptic response depends on ion current

Question 26

Na+ channels are depolarized by what

Answer 26

acetylcholine

Question 27

Cl- channel is

Answer 27

hyperpolarized by GABA

Question 28

Sponges

Answer 28

no neurons but still have basic cell physiology

Question 29

Ganglia

Answer 29

collections of neuronal cell bodies= sites of integration

Question 30

Cephalization

Answer 30

concentration of neurons/ ganglia in a "head" or region

Question 31

Somatic

Answer 31

voluntary control, drives skeletal muscle

Question 32

Autonomic

Answer 32

involuntary control, helps coordinate includes sympathetic and parasympathetic

Question 33

Parasympathetic

Answer 33

organ specific, "rest and digest", activity targets organs, controls smooth muscles and different glands

Question 34

Preganglionic Neurons

Answer 34

-in CNS -brainstem or spinal cord -myelinated axons -transmit signals from CNS to autonomic ganglia (ganglia outside CNS)

Question 35

Postganglionic Neurons

Answer 35

-neurons located in autonomic ganglia (outside CNS) and part of PNS -unmyelinated axons -transmit signals from autonomic ganglia to target organs -smooth, cardiac muscle or glands

Question 36

Neurotransmitter

Answer 36

-chemical messenger released by neurons that can transmit signals across synapses to target cells -classified into; acetylcholine, norepinephrine, dopamine, serotonin, etc -excitatory or inhibitory effects on target cell, depending on type of cell

Question 37

Receptors

Answer 37

-protein molecule located on surface of or within target cell that can bind specifically to a neurotransmitter or hormone -mediate biological effects of neurotransmitters or hormones by initiating intracellular signaling pathways when activated by the binding of a neurotransmitter or hormone -classified by structure, function, and type of signaling molecule they bind to