Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuro Phys > NP Midterm > Flashcards

NP Midterm Flashcards

1
Q

List some physiological needs of the cells discussed in class:

A

Energy source, O2, environmental temperature, osmotic pressure, ion concentrations, removal of toxic compounds, defines against foreign organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The internal environment of the cells where cellular activities occur is called?

A

Intracellular Fluid = cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Plasma + interstitial fluid = _____________

A

Extra Cellular Fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

T or F

Many homeostatic mechanisms are aimed at maintaining the content of the ECF

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Name the parts of the Homeostatic System?

A

Sensors
Integrating Center
Effectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the set point?

A

Ideal level of a variable to be maintained

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Can homeostatic systems be entered contained within a single cell?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Sensors can be?

A

Sensory cells of the nervous system

Endocrine Cells or any cell in the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

An effective negative feedback system does what?

A

Shuts itself off before the effectors push the body to far in the other direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When the body is too hot, the temperature regulating centre in the Hypothalamus will activate an efferent pathway to activate sweat glands, increases heat loss and inhibits skeletal muscles from shivering. In this example the hypothalamus, the skeletal muscles, and the sweat glands represent what part of a feedback system?

A

Hypothalamus = integrating centre
Sweat Glands = effectors
Skeletal muscles = effectors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe a Closed Loop Regulatory System

A

A self regulating system contained within the body that manages to maintain the variable within a normal range.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In a closed loop system the factors that cause change come from where?

A

Cells in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the Settling Point?

A

The ideal set point of the moment. The ideal set point for some variables change with physiological circumstances.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give examples of the set point changing with physiological circumstances:

A

Body temp changes during the course of the day and with infection
Body weight set point changes with age and activity level
Blood pressure set points change with posture, body size, activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does a change in the set point allow our body to do?

A

Adapt to new environments and new body states (puberty, starvation, growth)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a major difference between homeostatic and homeodynamic systems?

A

Homeodynamic can change the set point. Homeostasis has a very strict set point range ex) pH of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A change in one direction that leads to a further change in the same direction is an example of what type of feedback?

A

Positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The bad side of positive feedback is called?

A

Vicious Cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does a feed forward system work?

A

Within the CNS there are control centres that send out signals to direct actions in advance of feedback information. These are often seen in response to external stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are the external stimuli in the feed forward system considered to be open or closed loop input?

A

Open - bc we have no control over them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

From where to where in the body do primary messenger molecules convey information and please give examples of primary messengers.

A

From one cell to another

Neurotransmitters, cytokines…

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When do we need second messengers?

A

If the messenger is not lipid soluble.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Paracrine communication occurs between?

A

Cells within the same organ.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

T or F

Paracrine is considered to have extrinsic or local factors

A

False!

Intrinsic and local

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What type of communication occurs or acts on the same cell type that produced it? Give an example.

A

Autocrine

Follicular cells producing 10x more estrogen during first 12 days.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

A gap junction is an example of what type of cell to cell communication?

A

Juxtacrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When molecules produced by one system that control other systems this is an example of what type of communication?

A

Extrinsic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Hormones are an example of this type of communication? Why?

A

Endocrine - they are molecules that are secreted into the blood and reach target cells via the circulatory system.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Can hormones have a paracrine effect within the organs that produce them?

A

Yes!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the mechanism of action of a hormone?

A

It will influence all of a cell’s functions by altering enzyme activities and gene expression.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where are neurotransmitters released?

A

By neurons directly onto target cells at synapses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How do neurotransmitters affect cells?

A

They cause a change in membrane potentials by either opening or closing ion channels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Neurotransmitters can either be __________ like Na+ or __________ like K+

A

Excitatory

Inhibitory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Neuromodulators may reach the neurons in what two possible ways?

A

Through the circulatory system or be delivered directly onto the target cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How do neuromodulators work?

A

They alter a cell’s response to Neurotransmitters but do not change the membrane potential themselves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What type of cells can produce neuromodulators?

A

Immune cells, endocrine cells, and glial cells. Neurotransmitters can produce them as well.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are neuropeptides?

A

A short sequence of aa made by the nervous system that may act as neurotransmitters, modulator, growth factor or hormone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

The immune system will directly deliver these molecules onto target cells via the circulatory system?

A

Cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

T or F

Transmitters, modulators and hormones can also be cytokines

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Give some examples of molecules that fit into several categories of hormone, neurotransmitters, and neuromodulators, and cytokines

A

Norepinephrine
Dopamine
Serotonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

________ is a cytokine that has a neuromodulatory effect on emotions

A

Interferon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Describe the mechanism of action of all primary messenger molecules

A

Act by binding to a protein receptor
Initiate a change in the receptor structure
Chemical reactions within the cell
Physiological changes in the cell’s activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Give an example of an ion channel that is also the receptor

A

Nicotinic Acetyl Choline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Does the Nicotinic Acetyl Choline ion channel use secondary messengers?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What type of receptors use regulatory proteins -> G Proteins

A

Muscarinic Receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Intracellular signaling molecules that convey information from the cell membrane to the inside of the cell are known as?

A

Secondary messenger molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

List the different type of 2dary messenger complexes:

A 
Cyclic AMP
Cyclic GMP
Diacyl Glycerol
Inositol Triphosphate 
Ca++/Calmodulin
Prostoglandins
Leukotrienes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

The binding of the primary messenger to a receptor on the outside of the cell acts through what regulatory protein located in the cell membrane?

A

G Proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

The 2dary messengers will activate what kind of enzymes? What do these enzymes do?

A

Protein Kinases that phosphorylate proteins, or elevate intracellular Ca++ levels or cause other changes in cell function.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What does phosphoylation of proteins cause?

A

Changes the shape and activity of the protein (opens or closes channels, activates or inhibits enzymes, activating or inhibit gene expression.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Increased intracellular Ca++ can bind to a variety of proteins and causes changes in: (3)

A

The cytoskeleton structure
Actin-Myosin interactions -> cell contraction
Enzyme activity -> changes in cellular function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

The more receptors/cell - the more or less the primary messenger is needed to get a response?

A

Less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What will cause a cell to be more sensitive to a messenger?

A

The more receptors a cell has for the primary messenger.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Give an example of up regulation in the body in regards to muscle neuron innervation

A

If a muscles loses its motor neuron innervation there will be an increase in the number of Acetylcholine receptors on the muscle. More sensitivity!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What occurs more quickly: up or down regulation?

A

Down regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What does the body do to the receptors in down regulation?

A

The receptor may either be destroyed or recycled back to the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

A mechanism of addiction is an example of up or down regulation in the body?

A

Down - the more cocaine a person uses, the more receptors for Cocaine are lost -> need more of the drug to get the same effect on the cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

HANDOUT 2

A

HANDOUT 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

The Extracellular fluid is made up of: (2)

A

Plasma and Interstitial Fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Is the Cytoplasm Intracellular or Extracellular fluid?

A

Intracellular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What part of the cell has largely negatively charged proteins? What ions are more abundant here?

A

Inside

K+ , PO4-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Outside of the cell we find more of these ions (3)

A

Sodium Na+
Chlorine Cl-
Calcium Ca++

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Cytoplasmic levels of what ion activate muscle contraction?

A

Ca++

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What is meant by “electrochemical gradients”

A

When the membrane becomes permeable to specific ions they will move according to their electrochemical gradients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What is Kinetic energy?

A

Energy in use for work ( movement of objects through space and or given off as heat)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What controls movement of molecules across the cell membrane?

A

Simple Diffusion *Osmosis
Facilitated Diffusion
Active Transport
Endocytosis and Exocytosis

67
Q

Of all the control mechanisms for movement of molecules across cell membranes give an example of carrier mediated .

A

Facilitated Diffusion

Active Transport

68
Q

This type of diffusion depends on random motion of molecules.

A

Simple

69
Q

Is Simple Diffusion passive or active?

A

Passive

70
Q

Name the Laws of Diffusion

A 
Concentration Gradient
Surface Area
Distance
Temperature 
Size and Shape of Molecules 
Electromotive Forces
71
Q

What happens to diffusion when you increase strength?

A

Increase rofd

72
Q

What other LOD will increase the rofd?

A

Increased surface area!

73
Q

How does temperature effect diffusion?

A

Increase temperature = increased rate of random movement = increased diffusion

74
Q

If we increase mass or volume what happens to the rofd?

A

Decreased

75
Q

Of the Laws of Diffusion this one is said to be 2 dimensional

A

Surface Area

76
Q

What Law of Diffusion is 1 dimensional?

A

Distance

77
Q

Aka for Electromotive Force EMF

A

Electrical potential energy across the cell membrane

aka “Membrane Potential”

78
Q

Define the K+ Equilibrium Potential

A

The electrical potential across the membrane that exactly balances the concentration gradient force.

79
Q

What type of substances can cross the cell membrane?

A

Fats, Cholesterols, Steroid Hormones, Alcohol, Gasses: No2, O2, N2, CO2

80
Q

T or F

The more lipid soluble the quicker it moves through a cell membrane

A

True

81
Q

Give examples of some polarized molecules that cannot cross the phospholipid membrane

A

Glucose

Amino Acids

82
Q

Name the three possible membrane channel states: (3)

A

Closed - but openable
Open
Inactivated - closed and cannot be reopened in this state.

83
Q

What does the open or closed state of membrane channels depend on?

A
  1. Ungated Channels aka leaky channels - always open
  2. Voltage Gated - channel depends on the electrical charge across the membrane
  3. Ligand Gated Channels aka Chemically gated.
84
Q

In the resting state the channels are ________.

A

Closed

85
Q

What chemical messenger controls many of the Ligand Gated Channels?

A

Neurotransmitters

86
Q

Describe how polar and non polar molecules cross the cell membrane.

A

Polar needs: 1. ion specific protein channels and their electrochemical gradient allows their simple diffusion.
2. Carrier proteins
3. Endocytosis or exocytosis
Nonpolar: Simple Diffusion

87
Q

How does water move in the body?

A

Down its concentration gradient from a region of high water concentration to low water.

88
Q

A solution with high water concentration & has little solute would have high or low osmotic pressure?

A

Low osmotic pressure

89
Q

What would make for high osmotic pressure?

A

A solution with high solute concentration and has little water

90
Q

In terms of osmotic pressure, how will water move?

A

Water will move to the region with the highest osmotic pressure.

91
Q

Solute particles that cannot cross the cell membrane are said to be:

A

Osmotically Active Particles

92
Q

What do Osmotically active particles do to water?

A

Exert osmotic force on water ex) they draw water to them as a sponge soaks up water.

93
Q

How is osmotic pressure calculated?

A

The number of dissolved particles/amount of solvent

94
Q

T or F

The lower the osmotic pressure the less water is in the solution

A

False - Higher osmotic pressure = less water

95
Q

What is the pure water osmotic pressure?

A

Zero

96
Q

What type of particles will contribute 2 osmotically active particles?

A

NaCl -> Na to Cl

97
Q

How is Osmolarity calculated?

A

Osmoles/litre of solution

98
Q

How is an osmolar solution made?

A

By weighing the solute and then adding just enough solvent to bring the solution to a final volume of 1 litre.

99
Q

How is an Osmolal solution made?

A

Weighing both the solute and the solvent - solvents change density with changes in temp, but weigh of a specific number of molecules doesn’t change.

100
Q

The composition of an Osmolal or Osmolar is more exact?

A

Osmolal

101
Q

Cells have an internal osmotic pressure of?

A

300 mOsmoles

102
Q

What is tonicity?

A

The ability of a solution to move water across the cell membrane or solution.

103
Q

A solution that is hypertonic to a cell will do what?

A

Pull water out of a cell. Cell shrinks as water leaves.

104
Q

When a solution is hypotonic to a cell where does water move?

A

Pulls water into a cell.

105
Q

A solution that causes no net water movement is said to be?

A

Isotonic

106
Q

What can cause a cell to burst?

A

If enough water moves into the cell and causes swelling which disrupts the structure and interrelationships of the cell’s organelles.

107
Q

T or F

A solution’s Osmotic pressure is the same as tonicity

A

False

108
Q

What is solvent drag?

A

When particles that are permeable to the cell membrane move down their concentration gradients into the cell and drag water with them.

109
Q

What is meant by a Transport Maximum with Facilited Diffusion and Carrier Proteins?

A

That the carrier proteins are saturated.

110
Q

Does Facilitated Diffusion require energy?

A

No

111
Q

With facilitated diffusion how does the molecule to be transported get into the cell?

A

The molecule will bind to a part of the carrier protein on the outside of the cell -> carrier protein changes shape such that the molecule is now on the inside of the cell and the molecule than is released from the carrier protein.

112
Q

This type of transport requires energy

A

Active

113
Q

When is Active Transport used?

A

To transport molecules against their concentration gradient

114
Q

Primary Active Transport works for these ions: (5)

A

Na, K, Ca, H, Cl

115
Q

Give an example of a Counter-transport system

A

Na/K pump

116
Q

How many binding sites for Na and K are there on the cell?

A

3 binding sites for Na on the inside of the cell

2 binding sites for K on the outside of the cell

117
Q

This enzyme helps with the phosphorylation of the carrier protein in the sodium potassium pump

A

ATPase

118
Q

When the sodium potassium pump is pumping more positive charges out of the cell this is called?

A

Hyperpolarizes the cell membrane making it more negative on the inside.

119
Q

What is Secondary Active Transport?

A

When energy is used to create a concentration gradient for one molecule by a primary active pump, the concentration gradient for that molecule is then used to transport another molecule against its concentration gradient.

120
Q

Give an example of a Secondary Active Transport system

A

Na+ and glucose. Sodium moves down its concentration gradient from outside the cell to inside.

121
Q

What makes a Secondary Active Transport system “secondary”

A

The need for 2 separate carrier proteins.

122
Q

This is the theoretical electrical force needed across the membrane to balance the forces acting upon the gradient: concentration and EMF

A

Nernst Equation

123
Q

What is the equilibrium potential for Na+?

A

+65 mV

124
Q

How did the Goldman-Hodgkin-Katz equation expand on the Nernst equation?

A

It took into consideration the reality that the membrane potential is determined by several ions and membrane permeability to each ion.

125
Q

Where do action potentials happen?

A

Axons

126
Q

What happens when you increase the frequency of the AP on the axon?

A

Increases the strength of the message you are trying to get through.

127
Q

If a message is really important where will it synapse?

A

Closer to the cell body

128
Q

Where do local graded potentials occur? Why

A

On the dendrites and cell bodies due to Ligand gated ion channels.

129
Q

T or F

Graded potential are proportional to the size and strength of the stimulus.

A

True

130
Q

Post synaptic potentials can be either ________ or ________

A

Excitatory or Inhibitory

131
Q

When Na+ or Ca++ enter the cell and the membrane becomes closer to threshold potential (less negative) this represents what type of post synaptic potential?

A

Excitatory

132
Q

Give an example of an Inhibitory Post Synaptic Potential

A

Open K+ channels -> K+ moves out
OR
Open Cl- channels -> Cl- moves in
*Membrane potential is more negative and further from threshold.

133
Q

What is the equilibrium potential for K=?

A

-90 mV

134
Q

This type of 1ary messenger molecule will activate their receptors which brings about change in metabolic processes in neurons, often via G protein coupled to a second-messenger system.

A

Neuromodulators

135
Q

What has faster communication neurotransmitters or neuromodulators?

A

Neurostransmitters

136
Q

Neuromodulators tend to be associated with slower body events such as:

A

Learning
Development
Motivational States

137
Q

Exocytosis is usually linked to up or down regulation?

A

Up

138
Q

What ca secondary messenger systems do to the postsynaptic cell?

A
  1. Can open specific ion channels

2. cAMP or cGMP activation, enzyme activation, gene expression activation.

139
Q

When the postsynaptic receptor is inhibitory what will happen?

A

It will open CL- and/or K+ channels to make the inside of the cell more negative.

140
Q

What is an action potential?

A

A rapid change in the membrane potential that spreads in nerve fibres by voltage-gated ion channels.

141
Q

What ion fluxes into the cell during Depolarization?

A

Na+

142
Q

This ion rushes into the cell during Repolarization

A

K+

143
Q

What does hyperpolarizaton prevent?

A

The neuron from receiving another stimulus during this time or from the signal coming backward.

144
Q

Why is the resting membrane potential at -90mV if the equilibrium potential for K+ is -94mV?

A

The membrane has K+/Na+ leak channels (100x more permeable to K+ than Na+ and free movement of K+ brings the EMF close to K+ equilibrium potential. Opposed by Na+ entry (-86) and restored in part by Na+/K+ pump.

145
Q

What determines the resting potential of a cell?

A

The balance of the permeabilities of ions

146
Q

Where do Action Potentials occur on the cell?

A

Axon

147
Q

What will tell the strength of the message you are trying to get through with an Action Potential?

A

The frequency of the Action Potential

148
Q

What is non decremental conduction?

A

“All or None” magnitude propagated along an axon membrane without a change in magnitude.

149
Q

What causes decremental conduction of membrane potentials on the dendrites?

A

Diminishing EPSP with distance from the opened channels due to the small amount of cytoplasm in the dendrites - high resistance to flow and leak of K= ions out of the cell membrane.

150
Q

Where does non decremental conduction take place?

A

Soma - due to the large amount of cytoplasm and surface area of the soma, any membrane potential that occurs anywhere on the soma will be fully spread over the entire membrane.

151
Q

Summing the effects of synapses over space is called?

A

Spatial Summation

152
Q

What is temporal summation?

A

When several action potentials on the presynaptic cell release neurotransmitters one after another, their effects on the post synaptic cell add.

153
Q

Threshold Potential is reached where?

A

On the hillock of the axon where the highest density of voltage gated Na+ channels exists.

154
Q

Why don’t action potentials occur on the soma or dendrites?

A

Because they do not have enough voltage gated Na+ channels .

155
Q

How do graded potentials on the soma maintain the EPSP’s and IPSP’s?

A

Neurotransmitters will open channels for a long time (100’s of msec) and generate multiple action potentials.

156
Q

Describe the resting stage of an AP

A

both Na+ and K+ voltage channels are closed.

157
Q

Na+ ion channels are inactivated when the membrane potential reaches?

A

+ 30 mV

158
Q

What is the overall effect of the Na+/K+ pump?

A

To make the inside of the cell more negative than it would otherwise be.

159
Q

In what scenario would no action potential occur?

A

If the stimulus fails to open enough Na+ channels.

160
Q

What will determine the magnitude of an action potential?

A

The concentration gradient and EMF for Na+ which will drive Na+ into the cell until the channels become inactivated at about +30mV

161
Q

What is the time frame of the Absolute Refractory Period?

A

Technically begins as soon as the threshold potential is reached and lasts until the voltage gated Na+ channels shift from being inactivated to being closed but openable.

162
Q

When will the Na+ channels shift back into closed but openable?

A

When the membrane potential is restored to resting potential.

163
Q

Define Threshold stimulus

A

A stimulus with just enough strength to change the membrane from resting potential to threshold stimulus.

Neuro Phys (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions