Biology 141 Exam #1

Front 1

Nerves

Back 1

a bundle of nerve fibers (axons) wrapped in fibrous connective tissue

Front 2

Ganglia

Back 2

a knotlike swelling in a nerve where neuron cell bodies are concentrated

Front 3

What are the two major subdivisions of the nervous system?

Back 3

1. Central Nervous System (CNS)
2. Peripheral Nervous System (PNS)

Front 4

What are the two major subdivisions of the Peripheral Nervous System (PNS)?

Back 4

1. Sensory Division (afferent)
2. Motor Division (efferent)

Front 5

sensory division

Back 5

carries sensory signals from various receptors to the CNS

Front 6

carries signals from the CNS to the effector organs

Back 6

motor division

Front 7

autonomic nervous system (visceral motor division)

Back 7

involuntary, and responses of this system and its receptors are visceral reflexes

Front 8

What are the 2 subdivisions of the Visceral Motor Division (autonomic nervous system)?

Back 8

1. Sympathetic Division
2. Parasympathetic Division

Front 9

Which division of the autonomic nervous system has this function: arouse body for action, accelerates heart and respiration rate

Back 9

Sympathetic

Front 10

Which division of the autonomic nervous system has this function: calming effect, slows heart rate and breathing

Back 10

Parasympathetic

Front 11

What are the 3 functional properties of Neurons?

Back 11

1. Excitability
2. Conductivity
3. Secretion

Front 12

ability to respond to environmental changes (stimuli)

Back 12

Excitability

Front 13

ability to transmit electrical signals

Back 13

conductivity

Front 14

release of a chemical neurotransmitter which crosses the physical gap between cells and stimulates the next cell

Back 14

secretion

Front 15

What are the 3 classes of Neurons?

Back 15

1. Sensory neurons (afferent)
2. Interneurons (association neurons)
3. Motor Neuron (efferent)

Front 16

Which class of Neurons:
1. are Specialized to detect stimuli
2. Transmit information about them to the CNS

Back 16

sensory neurons

Front 17

Which class of Neurons:
1. lie entirely within the CNS
2. receive signals from many neurons and carry out the integrative function "making decisions"

Back 17

interneurons

Front 18

Which class of Neurons:
1. send signals out to muscles and glands (the effectors)

Back 18

motor neurons

Front 19

the body control center of the neuron

Back 19

soma

Front 20

branches coming from soma; primary site for receiving signals from other neurons

Back 20

dendrites

Front 21

specialized for rapid conduction of nerve signals away from dendrites and soma

Back 21

axon

Front 22

wraps axon; speeds rate of electrical conduction; formed by Schwann cells in PNS and oligodendrocytes in CNS

Back 22

myelin sheath

Front 23

Diseases of myelin sheath:
- myelin sheaths in the CNS deteriorate and are replaced by scar tissue
- nerve conduction disrupted (double vision, tremors, numbness, speech defects)

Back 23

multiple sclerosis

Front 24

swelling that forms a synapse between other cells

Back 24

axon terminal

Front 25

- support and protect the neurons
- bind neurons together and form framework for nervous tissue

Back 25

neuroglia or glial cells

Front 26

cellular mechanisms for producing electrical potentials and currents; basis for neural communication and muscle contraction

Back 26

electrophysiology

Front 27

a difference in the concentration of charged particles between two points

Back 27

electrical potential (voltage)

Front 28

a flow of charged particles

Back 28

electrical current

Front 29

voltage across the membrane; about -70mV in a neuron

Back 29

resting membrane potential (RMP)

Front 30

Which ions have the greatest influence on resting membrane potential (RMP)?

Back 30

potassium ions

Front 31

What is concentrated in the ICF (inside cell)?

Back 31

potassium ions

Front 32

What is concentrated in the ECF (outside cell)?

Back 32

sodium ions

Front 33

Na+/K+ pumped out ___ Na+ for every ___ K+ it brings in

Back 33

3, 2

Front 34

dramatic change in voltage produced by voltage-regulated ion gates in the plasma membrane; a rapid up-and-down shift in the membrane voltage

Back 34

action potential

Front 35

when threshold is reached, neuron "fires" and produces an _____ _______.

Back 35

action potential

Front 36

Na+ and K+ switch places across the membrane during an ______ ______.

Back 36

action potential

Front 37

which type of membrane potential follows an "all or none law"?

Back 37

action potential

Front 38

the period of resistance to stimulation

Back 38

refractory period

Front 39

used to communicate across synaptic cleft

Back 39

neurotransmitters

Front 40

what are the 4 major categories of neurotransmitters?

Back 40

1. Acetylcholine (ACh)
2. Amino Acids
3. Monoamines
4. Neuropeptides

Front 41

the first neuron has a soma in the brainstem or spinal cord

Back 41

presynaptic neuron

Front 42

has relatively short preganglionic and long postganglionic fibers

Back 42

sympathetic division

Front 43

small myelinated fibers that travel from spinal nerve to the ganglion by the way of the white communicating ramus (myelinated)

Back 43

preganglionic fibers

Front 44

leave the ganglion by way of the gray communicating ramus (unmyelinated)

Back 44

postganglionic fibers

Front 45

each ______ cell branches and synapses on 10 to 20 ____ cells.

Back 45

preganglionic; postganglionic

Front 46

secretes steroid hormones

Back 46

adrenal cortex

Front 47

-secretes a mixture of hormones into bloodstream
- essentially a sympathetic ganglion
- also function as neurotransmitters
-consists of modified postganglionic neurons without dendrites or axons

Back 47

adrenal medulla

Front 48

the nervous system of the digestive tract

Back 48

enteric nervous system

Front 49

is secreted by ALL preganglionic neurons in both divisions and the postganglionic parasympathetic neurons

Back 49

acetylcholine (ACh)

Front 50

what are the 2 types of cholinergic receptors?

Back 50

1. Muscarinic
2. Nicotinic

Front 51

all cardiac muscle, smooth muscle, and gland cells have _____ ______.

Back 51

muscarinic receptors

Front 52

on all ANS postganglionic neurons, in the adrenal medulla, and at neuromuscular junctions of skeletal muscle

Back 52

nicotinic receptors

Front 53

-adrenergic receptors
-usually excitatory

Back 53

alpha

Front 54

-adrenergic receptors
- usually inhibitory

Back 54

beta

Front 55

- increased blood flow
- increased secretion

Back 55

vasodilation

Front 56

- decreased blood flow
- dcreased secretion

Back 56

vasoconstriction

Front 57

- neuron cell bodies
- site of information processing, synaptic integration
- unmyelinated

Back 57

gray matter

Front 58

- myelinated axons
- transmits signals from one part of the CNS to another

Back 58

White matter

Front 59

neurons that stimulate muscle cells

Back 59

motor neurons

Front 60

motor neurons travels from CNS and synapse with muscle cells at the _________.

Back 60

neuromuscular junction (NMJ)

Front 61

Which type of neurons always release ACh?

Back 61

Preganglionic neurons

Front 62

What are the 2 classes of chemical synapses?`

Back 62

1. Cholinergic
2. Adrenergic

Front 63

preganglion neuron secretes acetylcholine (ACh)

Back 63

cholinergic

Front 64

preganglion neuron secretes norepinephrine

Back 64

adrenergic

Front 65

embedded in membrane and are usually involved in transport or act as chemical messengers

Back 65

integral proteins

Front 66

diffusion in which a substance requires a carrier molecule or moves through a water filled protein channel

Back 66

facilitated diffusion

Front 67

moves solutes against their concentration gradient, requires energy (ATP) and carrier proteins

Back 67

active transport

Front 68

energy source is ATP

Back 68

primary active transport

Front 69

energy course is ion gradient, derived from ATP

Back 69

secondary active transport

Front 70

maintains the resting membrane potential

Back 70

sodium potassium pump

Front 71

- site of aerobic respiration
- where majority of ATP is produced
- "power plant" of cell

Back 71

mitochondria

Front 72

modifies, concentrates, and packages proteins and lipids; "traffic director"

Back 72

Golgi apparatus

Front 73

- dispose of bacteria and debris
- "demolition crew"

Back 73

lysosomes

Front 74

- all preganglionic neurons are _______
- secrete Ach

Back 74

cholinergic

Front 75

- all postganglionic neurons are _____
- always excited by Ach

Back 75

nicotinic

Front 76

- contractile unit of myofibril
- "functional unit of muscle"
- striations of muscle cell are evident by the arrangement of myofilaments

Back 76

sarcomere

Front 77

each filament conists of many myosin molecules whose heads protrude at opposite ends of the filament

Back 77

thick myofilaments (myosin)

Front 78

consists of two strands of actin subunits twisted into a helix plus two types of regulatory proteins (troponin and tropomyosin)

Back 78

thin myofilaments (actin)

Front 79

have active sites that bind with the globular head of myosin; each filament has 2 of these that are intertwined

Back 79

actin

Front 80

- plasma membrane of muscle cell
- contains T-Tubules (tube-like structures that protrude into muscle cells) allow impulses to reach inside of cell

Back 80

saraclemma

Front 81

-cytoplasm of muscle cell
-contains large amount of stored glycogen (ATP source)
-contains large amount of myoglobin (oxygen storage; required for ATP production)

Back 81

sarcoplasm

Front 82

axon from nerve branches and forms communication with muscle fiber

Back 82

neuromuscular junction (NMJ)

Front 83

stimulation of muscle by motor neuron
generation of action potential
facilitated by T-Tubule

Back 83

excitation

Front 84

development of tension in muscle which may result in shortening; "sliding filament theory"

Back 84

contraction

Front 85

return of muscle to resting state and length (muscle twitch)

Back 85

relaxation/repolarization

Front 86

involuntary branch of the PNS that helps maintain homeostasis and optimal body function; we do not control it consciously

Back 86

autonomic nervous system

Front 87

- the ability of an external solution (ECF) to have an effect on the volume and pressure of the fluid inside the cell (ICF)
- comparing concentrations

Back 87

tonicity

Front 88

-70mV

Back 88

in resting membrane potential, the result ICF has a voltage of ____.