the nervous system

Question 1

what are the three functions of the nervous system

Answer 1

sensory input, integration and motor output

Question 2

neurons

Answer 2

nerve cells that transfer information within the body

Question 3

ganglia

Answer 3

simple clusters of neurons instead of a brain in simple organisms

Question 4

what is the function of a neuron ?

Answer 4

transmission of signals

Question 6

what are dendrites

Answer 6

branched extensions that receive signals from other neurons

Question 7

What is the axon?

Answer 7

longer extension than the dendrites transmitting signals

Question 8

where are most of a neurons organelles?

Answer 8

in the cell body

Question 10

what are glia cells

Answer 10

support the neuron and are for structural integrity and function

Question 11

what is membrane potential?

Answer 11

a voltage(difference in electrical charge) accross its plasma membrane

Question 12

how are messages transmitted?

Answer 12

as changes in membrane potential

Question 13

what is the resting potential?

Answer 13

the membrane potential of a neuron not sending signals. ion pumps and ion channels maintain the resting potential of a neuron. K+ higher inside, Na+ higher outside.

Question 14

what is the refractory period a result of?

Answer 14

a temporary inactivation of the Na+ channels.

Question 15

refractory period

Answer 15

is a period of normal repolarization when the Na+K+ pump restores the membrane to its original polarized condition. It prevents the backward signal transmission

Question 16

how does the action potential travel

Answer 16

regenerating itself along the axon

Question 17

what direction to action potentials travel?

Answer 17

travel in only one direction toward the synaptic terminals

Question 18

what causes action potentials speed to increase?

Answer 18

the axons diameter
and the myelin sheath

Question 19

where are action potentials formed?

Answer 19

only at nodes of Ranvier, gaps between shwann cells in the myelin sheath

Question 20

saltatory conduction

Answer 20

jumping between the nodes of Ranvier

Question 21

synapse

Answer 21

is a junction between cells controlling communication

Question 22

electric synapses

Answer 22

direct current flow between neurons

Question 23

chemical synapses

Answer 23

neurotransmitter carries information across the synapse

Question 24

presynaptic cell

Answer 24

releases neurotransmitters in synaptic vesicles

Question 25

what causes the release of the neurotransmitter

Answer 25

the action potential

Question 26

postsynaptic cell

Answer 26

receives signals

Question 27

what happens neurotransmitters after release?

Answer 27

can diffuse, be reabsorbed or degraded

Question 28

Cephalization

Answer 28

is the clustering of sensory organs at the front end of the body

Question 29

central nervous system

Answer 29

Brain and spinal cord

Question 30

grey matter

Answer 30

contains cell bodies and dendrites

Question 31

white matter

Answer 31

contains myelinated axons

Question 32

peripheral nervous system

Answer 32

transmits information the the CNS. includes cranial and spinal nerves two components: motor system& autonomic nervous system

Question 33

reflex

Answer 33

the bodys automatic response to a stimulus

Question 34

afferent neurons

Answer 34

transmit information to the CNS

Question 35

efferent neurons

Answer 35

transmit information away from the CNS

Question 36

what does the brainstem do?

Answer 36

coordinates and conducts information between brain centers

Question 37

what are the three parts of the brainstem ?

Answer 37

the midbrain, the pons, and the medulla oblongata

Question 38

the midbrain

Answer 38

sensory integration

Question 39

the pons

Answer 39

breathing regulation

Question 40

medulla oblongata

Answer 40

controls vital functions

Question 41

cerebellum

Answer 41

coordinates motor functions involved in learning motor skills

Question 42

what is the diencephalon ?

Answer 42

the epithalamus, the thalamus, and the hypothalamus

Question 43

epithalamus

Answer 43

produces cerebrospinal fluid

Question 44

thalamus

Answer 44

processes sensory and motor information

Question 45

hypothalamus

Answer 45

regulates homeostasis and survival behaviours

Question 46

cerebrum

Answer 46

two hemispheres connected by corpus callosum. four lobes: frontal, temporal, occipital & parietal. controls voluntary movement and cognitive functions

Question 47

what system processes emotions

Answer 47

the limbic system

Question 48

what is the limbic system?

Answer 48

Is a ring of structures around the brainstem that includes the amygdala, hippocampus and parts of the thalamus.

Question 49

where is emotional memory stored?

Answer 49

the amygdala

Question 50

what part of brain is short term memory?

Answer 50

the hippocampus

Question 51

where is long term memory stored?

Answer 51

the cerebral cortex

Question 52

what is the main input centre for sensory information to the cerebrum?

Answer 52

Thalamus

Question 53

what is the simplest type of nervous system arrangement found in cnidarians?

Answer 53

nerve net