Week 1: Introduction to Neuroscience

Question 1

The main functions of the nervous system are:

Answer 1

• control
• regulate
• communicate

Question 2

The main systems of the nervous system are:

Answer 2

• sensory systems
• memory systems
• associational systems

Question 3

What are the components of the CNS?

Answer 3

brain and spinal cord

Question 4

what are the 2 large divisions of the PNS?

Answer 4

Somatic Nervous System and Autonomic nervous system

Question 5

The autonomic nervous system contains the:

Answer 5

• somatic nervous system
• parasympathetic nervous system
• enteric nervous system

Question 6

The somatic nervous system contains:

Answer 6

• cranial nerves and branches
• spinal cords and branches

Question 7

what are the components of a neuron?

Answer 7

• dendrites
• soma
• axon hillock
• axon
• terminal branches

Question 8

What is the function of dendrites?

What is the function of soma?

Answer 8

Dendrites: receive all information!
Soma: where the info from the dendrites is directly related

Question 9

What is the function of the axon hillock? What is important about this component?

Answer 9

axon hillock connects the cell body and the axon.

It acts as a gateway to the axon. This is where the signal can die off or if it is important enough, it will go through to the axon.

Question 10

what is the job of the axon? What are two important structures that we see here?

Answer 10

to pass information along!

nodes of Ranvier and myelin

Question 11

The job of myelin is to help:

Answer 11

speed up the transference

Question 12

The job of the nodes of Ranvier is to:

Answer 12

speed up the signal

Question 13

This type of neuron has several dendrites and axons and it is considered to be the most common.

Answer 13

Multipolar neurons

Question 14

This type of neuron is sometimes found in the eyes or nose but is overall rare in humans. It classified as a single dendrite and a single axon, has 2 long axons and mostly found in invertebrates.

Answer 14

bipolar neurons

Question 15

These neurons come off the cell body, has bidirectional information, and is typically classified as going TOWARDS the PNS. It is almost exclusively in the PNS.

Answer 15

Pseudo Unipolar

Question 16

Sensory neurons are ___________ signals from the receptor to the CNS.

Answer 16

afferent

Question 17

What are the 3 types of sensory neurons?

Answer 17

• special sensory
• viscerosensory
• somatosensory

Question 18

Which sensory neurons are a conscious transmission from skin, muscle and joint receptors on the cortex?

Answer 18

somatosensory

Question 19

What are the 2 types of motor neurons?

Answer 19

efferent signals from CNS to effectors

Question 20

somatomotor neurons go from CNS to:

autonomic motor neurons go from CNS to:

Answer 20

1. Skeletal muscles (voluntary contractions)
2. Smooth muscle, cardiac muscle, glands (involuntary contractions)

Question 21

What are the characteristics of interneurons?

Answer 21

• The are found in the brain and spinal cord
• they are also called associative neurons.
• the connect sensory and motor neurons and mediate their functions

Question 22

A reflex is:

Answer 22

a unidirectional, rapid, predictable, and involuntary response to a stimulus.

Question 23

What is the neural pathway that controls a reflex?

Answer 23

sensory receptor → sensory neuron → interneuron → motor neuron → effector

Question 24

The flexor withdrawal reflex and the myotatic reflexes are types of:

Answer 24

Somatic reflexes

Question 25

The salivary reflex and pupillary reflexes are types of:

Answer 25

autonomic reflexes

Question 26

In the myotatic reflex, what is the purpose of the interneuron?

Answer 26

To inhibit motor neurons to the flexor muscles

Question 27

What is the flexor reflex?

Answer 27

painful stimulus → sensory receptor → sensory neuron → interneurons → motor neurons → excitation of flexors, inhibition of extensors

Question 28

what is the crosses extension reflex?

Answer 28

painful stimulus → sensory receptor → sensory neuron → interneuron crosses midline → motor neurons → excitation of extensors and inhibition of flexors.

Question 29

Glial cells are support cells. How many glial cells to every neuron?

Answer 29

10

Question 30

What are the 4 CNS glia or neuroglia?

Answer 30

* Astrocytes * oligodendrocytes * ependymal cells * microglia

Question 31

Astrocytes are crucial structures because:

Answer 31

* support cells * they are insulators * assist with tissue repair * impact neurotransmitter activity * assist with the blood brain barrier

Question 32

Ependymal cells line the ventricle and central canal of the walls. What structure do they form?

Answer 32

Choroid plexus

Question 33

What is the importance of CSF as it relates to Ependymal cells?

Answer 33

Ependymal cells help facilitate CSF exchange and these cells also aid in production of CSF.

Question 34

Microglia are the:

Answer 34

macrophages of CNS

Question 35

What are the functions of oligodendrocytes?

Answer 35

CNS myelin creation One cell can myelinate multiple axons

Question 36

astrocytes are the CNS equivalent of PNS structures called:

Answer 36

satellite cells

Question 37

The myelin is a:

Answer 37

mixture of proteins and phospholipids that wrap around the axon, forming a white insulating sheath.

Question 38

The myelin is not continuous. Instead, what structures run between the discontinuities of the myelin sheath?

Answer 38

Nodes of Ranvier

Question 39

The nodes of ranvier:

Answer 39

enable regeneration of action potentials and facilitates saltatory transmissions.

Question 40

What is the synapse?

Answer 40

a space for neurons to interact with each other. It can also be a space for neurons to interact with a target organ.

Question 41

What are the 3 components of a synapse?

Answer 41

* presynaptic nerve terminals * post synaptic element - dendrite, cell body, target cell * synaptic cleft

Question 42

what are the characteristics of an electrical synapse?

Answer 42

* bidirectional * tight junctions * gap junctions have large diameter pores for access * very fast communication but short latency * less common in nervous system than chemical synapses

Question 43

What are the characteristics of chemical synapses?

Answer 43

* greater distance between neurons (synaptic cleft) * slower process * receptor specific communication

Question 44

why are there more chemical synapses in the body than electrical synapses?

Answer 44

chemical synapses are more controlled, efficient and specific.

Question 45

What is occurring at stage 1?

Answer 45

transmitter is synthesize and then stored in vesicles

Question 46

what is occurring at stage 3?

Answer 46

depolarization of presynaptic terminal causing opening of voltage gated Ca2+ channels

Question 47

In step 6, that transmitter is being released via:

Answer 47

exocytosis

Question 48

What is occuring in stage 5 of this picture?

Answer 48

Ca2+ is causing the vesicles to fuse with presynaptic membranes

Question 49

What ion is more prevalent intracellularly?

Answer 49

K+

Question 50

Which ions are more prevalent as extracellular components and have crucial roles in maintaining the resting membrane?

Answer 50

Cl - and Na+

Question 51

Excitatory post synaptic potentials:

Answer 51

* cause depolarization of the cell * increase the likelihood of Na+ coming into the cell * increase likelihood of postsynaptic action potential

Question 52

Inhibitory post synaptic potentials:

Answer 52

* cause hyperpolarization of the cell * increases likelihood of Cl - going in the cell and hyperpolarizing * decreases likelihood of postsynaptic action potential

Question 53

What are temporal summations?

Answer 53

little graded potentials that build up

Question 54

what is spatial summation?

Answer 54

2 graded potentials that happen at the same time

Question 55

conduction velocity of the myelin sheath is dependent on:

Answer 55

* fiber diameter * presence of myelin * thickness of myelin * fiber classification

Question 56

What are the functions of neurotransmitters?

Answer 56

carry messages from neuron to neuron

Question 57

Glutamate is the primary: What is it involved in?

Answer 57

excitatory neurotransmitter. excitatory brain functions, learning, memory and synaptic plasticity

Question 58

Acetylcholine is vital to:

Answer 58

muscle contractions, autonomic functions, wakefulness, attentiveness, anger, sexuality

Question 59

GABA is the primary: It has functions in:

Answer 59

inhibitory neurotransmitter * inhibiting motor, sensory and cognitive neurons * sedation * reducing fear, anxiety and stress * pain inhibition

Question 60

Glycine is ionotropic or metabotropic?

Answer 60

only ionotropic.

Question 61

Where is glycine found?

Answer 61

Brainstem and spinal cord

Question 62

What is the specific PNS centered neuron?

Answer 62

Epinephine

Question 63

Which catecholamine is excitatory and inhibitory?

Answer 63

dopamine

Question 64

serotonin has a correlation to:

Answer 64

* sleep quality * Gi motility * mood stabilizer

Question 65

histamine is secreted:

Answer 65

in the hypothalamus but also found throughout the rest of the body.

Question 66

Histamine is ionotropic or metabotropic?

Answer 66

metabotropic