Exam 2: Chapter 12: Neurons

Question 1

Whole-animal integration involves the combination of:

Answer 1

sensory, endocrine, and CNS information processes

Question 2

What systems work together in different manners to control cells?

Answer 2

nervous system and endocrine system

Question 3

Neuron communication (3 basics)

Answer 3

send electrical signals down axons to target cells; communication is fast and the distance is determined by the length of the axon

Question 4

Signals transmitted to target cells will…

Answer 4

cause a response perhaps activating or inhibiting action of the cell

Question 5

endocrine cell communication (3 basics in comparison to neuron communication)

Answer 5

hormones enter the blood stream and travel to a target cell; action is slow and can travel anywhere that blood vessels go

Question 6

cells that are contacted by hormones must have

Answer 6

receptors for that specific hormone

Question 7

target cells of hormones respond according to

Answer 7

the nature of the signal

Question 8

neurons carry…

Answer 8

self-propagating electrical signals called action potential to their contacts

Question 9

neuron signals are received at the _____

Answer 9

sypase, often present on dendrites

Question 10

neurotransmitters travel across the _______

Answer 10

synaptic cleft between cells

Question 11

neuron signals typically start where

Answer 11

cell body or soma

Question 12

central nervous system (CNS)

Answer 12

consist of both the brain and the spinal cord

Question 13

peripheral nervous system (PNS)

Answer 13

consists of all nerves outside the CNS

Question 14

afferent neurons

Answer 14

sensory neurons that carry data to the CNS

Question 15

efferent neurons

Answer 15

start in the CNS and send instructions to target cells (muscles)

Question 16

interneruons

Answer 16

interface between sensory and motor neurons; only in the CNS in the gray matter of the spinal cord

Question 17

Signal may take ________ ms, and may have ____ signals per second

Answer 17

2-100ms, 100 per second

Question 18

Neuron signals provide what type of communication

Answer 18

spatial and temporal

Question 19

Hormones only have action with

Answer 19

cells and tissues with receptors for that hormone on thier surface

Question 20

how a target cells responds is generally by….

Answer 20

gene expression

Question 21

Nervous system controls:

Answer 21

fast, fine, specific muscle movements

Question 22

Endocrine system controls:

Answer 22

broad, longer actions like metabolic events

Question 23

Steps of the nervous system circuit/organization

Answer 23

1. a stimulus starts a reflex which begins a series of action potentials in sensory neurons
2. the action potential travel on afferent axons of sensory neurons to the CNS, excitatory contacts are made to interneurons
3. interneurons generate their own action potential
4. connect to efferent motor neurons who send axons to make contacts to muscles
5. response is produced

Question 24

Reticular theory:

Answer 24

nervous system cells run together without boundaries

Question 25

neuron doctrine:

Answer 25

neurons are anatomically distinct and are structural, functional, and developmental units of nervous system organization

Question 26

the type of neurons depends on...

Answer 26

the number of processes emanate from it's soma

Question 27

dendrites are...

Answer 27

the receptive or input element, carrying infomartion to the soma

Question 28

axons are...

Answer 28

the output element, carrying information away form the soma to other cells

Question 29

myelin

Answer 29

comes from the glial cells, insulates axons allowing them to transmit neuronal signals quickly and with minimal signal lost

Question 30

myelin is present in which types of animals

Answer 30

vertebrates (absent in invertebrates)

Question 31

without myelin, signaling down an axon would be

Answer 31

slower and would diminish with distance traveled

Question 32

glial cells

Answer 32

support neurons physically and metabolically

Question 33

what are the two types of glial cells?

Answer 33

schwann cells (PNS) and oligodendrocytes (CNS)

Question 34

oligodendrocytes

Answer 34

the myelinating cells of the central nervous system (CNS)

Question 35

astrocytes

Answer 35

located near to capillaries; acting as intermediates between the blood vessels and neurons; take up neurotransmitters and supply metabolic substrates to neurons; also have a roll in nervous system development and control extracellular ion levels

Question 36

microglia

Answer 36

control immune actions in nerve cells

Question 37

cell membranes

Answer 37

have passive electrical properties; resistance and capacitance

Question 38

all cells respond to....

Answer 38

electric currents, but only neuronal cells generate action potentials

Question 39

resting membrane potential (Vm)

Answer 39

the potential difference across the membrane

Question 40

Inside of the membrane is

Answer 40

less positive

Question 41

membrane resistance (Rm)

Answer 41

prevents ions from moving across the membrane

Question 42

an action potential results in

Answer 42

membrane depolarization; inside becomes more positive

Question 43

hyperpolarization

Answer 43

returns the membrane to its resting potential

Question 44

The nernst equation

Answer 44

membrane potentials depend on the selective permeability of ions; helpful to understand the relation between the concentration differences of a permeating ion across a membrane and the membrane potential equilibrium E=(RT/zF)ln(Cout/Cin)

Question 45

Inside the cell:

Answer 45

high concentration of K+ and negatively charged anions (A-)

Question 46

outside the cell:

Answer 46

high concentration of Na+

Question 47

the cell membrane is permeable to:

Answer 47

K+

Question 48

What causes the membrane potential to develope?

Answer 48

some K+ leaves the cell with the concentration gradient

Question 49

larger concentration difference across the membrane will result in

Answer 49

greater membrane potential

Question 50

ion concentration differences result from

Answer 50

active ion transport and from passive diffusion

Question 51

All cells keep the following concentrations

Answer 51

greater potassium level and a lesser sodium and chloride lever inside than outside

Question 52

the different ion concentrations between in and out of a cell is caused by

Answer 52

some ions are actively transported and others are passively moved

Question 53

Na+ and K+ exchange pump

Answer 53

ratio of 3 to 2 (3 sodiums out for every 2 potassium ions brought in), helps maintain the negative potential

Question 54

goldman equation

Answer 54

takes into account 2 ions at a time so it is more accurate

Question 55

The K+ level determines the resting membrane potential because

Answer 55

K+ is more permeable

Question 56

the action potential

Answer 56

occurs in excitable cells; voltage dependent, all or non signals; caused by voltage dependent changes in membrane permeabilities to ions

Question 57

ion channels are

Answer 57

voltage gates

Question 58

action potential starts with

Answer 58

depolarization

Question 59

what is resting membrane potential

Answer 59

-65mV

Question 60

Action Potential

Answer 60

***review slides from chapter 12 powerpoint***

Question 61

nodes of ranvier

Answer 61

gaps in the myelin sheath coating on the neural axon; allows the electrical impulse to move quickly down the axon

Question 62

Integration of cells involves

Answer 62

events within cells

Question 63

Control comes from the brain with....

Answer 63

sensory neurons providing feedback from sensory input

Question 64

Neuronal signals are .......

Answer 64

Fast and addressed

Question 65

Neurons provide connections to....

Answer 65

Very specific locations

Question 66

Endocrine cells .....

Answer 66

Broadcast hormones

Question 67

Where are hormones sent? What does this mean?

Answer 67

Hormones are sent wherever blood flows, so it is less specific

Question 68

Although the nervous systems and endocrine systems tend to control different processes, both systems can exert control over each other. Give an example

Answer 68

Nerves can control glands and sex hormones can effect neurons in the brain

Question 69

What are the 3 main theories that concern cellular organization?

Answer 69

Cell theory, reticular theory, and the neuron doctrine

Question 70

What does the cell theory state?

Answer 70

Organisms are made of cells and cells come from preexisting cells

Question 71

Neurons generally have what in terms of structure?

Answer 71

An axon and one or more dendrites

Question 72

Axonal connections from one axon to another generally made to what?

Answer 72

Dendritic spines