For exam 1 Flashcards
(282 cards)
1
Q
What are the 3 types of biological units?
A
Eukaryotic cells
Prokaryotic cells
Virus
2
Q
What makes up a eukaryote?
A
- Nucleus (sometimes more than 1)
- Membrane bound organelles
3
Q
What makes up a Prokaryote?
A
-No true nucleus or organelles
4
Q
What does the size of a organism (specifically a human) depend on?
A
The number of eukaryotic cells
5
Q
Why do red blood cells not have a nucleus?
A
To allow for more hemoglobin and oxygen to bind
6
Q
What is cell size limited by?
A
Respiration, the bigger the cell the longer it takes to diffuse substances
7
Q
How does diffusion time change?
A
It grows exponentially
8
Q
What are the 2 major components of a human cell?
A
- Nucleus
- Cytoplasm
9
Q
What is the protoplasm?
A
Everything in a cell
10
Q
What is contained in the nucleus?
A
All the genes
11
Q
What is contained in the cytoplasm?
A
Cytosol and non-nuclear organelles
12
Q
What are the 4 basic types of cells in the body?
A
- Muscle
- Nerve
- Epithelial
- Connective
13
Q
What does muscle do?
A
Produce force and enable movement
14
Q
What do nerves do?
A
Initiate and conduct electrical signals
15
Q
What does epithelial tissue do?
A
Secrete and absorb ions and other molecules
16
Q
What type of cells are found in the digestive system?
A
Epithelial, from mouth to anus
17
Q
What does connective tissue do?
A
Connect, anchor, and support structures of the body
18
Q
What does the plasma membrane do?
A
- Structure
- Control movement in & out of cell
- Detect chemical messengers
- Link cells
- Anchor cell proteins (channels, transporters, receptors) to cell surface
- Contains growth factors
19
Q
What is a tissue?
A
Bunch of cells of same type working together
20
Q
What is an organ?
A
Bunch of cells not of the same type working together
21
Q
What composes membranes?
A
- Lipids
- Proteins
- Cholesterol (produced by body w/little food effect)
- Phospholipids
22
Q
What are phospholipids made up of?
A
- Hydrophobic tails
- Hydrophilic heads
23
Q
What molecules have a hard time getting through the lipid bilayer?
A
Charged particles due to repulsion of the hydrophilic heads
24
Q
What is a glycoprotein?
A
Protein base with sugar segments attached
25
What is a proteoglycan?
Sugar base with protein segments attached
26
What are integral proteins in a lipid bilayer?
- Traverse entire membrane
| - Form many channels or act as carrier proteins (transporters)
27
What essential job do integral proteins have in the cell membrane?
Hold together the cell membrane
28
What are peripheral proteins in the lipid bilayer?
- Attached to inner surface of membrane in connection w/ integral proteins
- Act as enzymes and catalyze many necessary reactions
29
What are peripheral proteins involved in?
Signal transduction
30
What happens when a peripheral protein is pulled off the cell membrane?
It doesn't fall apart
31
What surrounds the nucleus?
Porous membrane called nuclear envelope
32
What is a pore?
Always open and large hole
33
What are aquaporins?
Pores in cell membrane allowing water to move through it
34
What are chromosomes?
Balled up chromatin
35
What is chromatin?
Genetic material that is stretched thin (chromathin)
36
What does the nucleolus in the nucleus do?
- Contains protein and ribosomal RNA
| - Forms ribosome precursors
37
What do ribosomes do?
-Synthesize proteins
38
Where are ribosomes found?
- Cytoplasm
| - Can be found in association with endoplasmic reticulum as well
39
What is the Endoplasmic reticulum?
Network of vesicular structures with walls made of lipid bilayer
40
What is Rough (granular) endoplasmic reticulum?
Has ribosomes attached, proteins produced here by ribosomes are released into the ER
41
What is Smooth (agranular) endoplasmic reticulum?
- No ribosomes
| - Involved in synthesis of lipids and holds calcium
42
How is the ER shaped?
In folds that are continuous
43
What does the golgi apparatus do?
-Process and package proteins as they exit ER
44
What happens to proteins after the leave the golgi apparatus?
Placed in vesicles which are transported to various parts of the cell or released from the cell in secretory vesicles
45
What do mitochondria primarily do?
Produce ATP for the cell
46
What makes up the mitochondria?
- 2 lipid bilayer membranes
| - Oxidative enzymes
47
What are cristae?
Infoldings inside of mitochondria that contain cytochromes and are where oxidative enzymes do their work
48
What determines the number of mitochondria you have?
The amount your mother has
49
How does ATP made by the mitochondria move?
It is released into the cytoplasm and diffuses to where it is needed
50
What are lysosomes?
Vesicular organelles formed by the golgi apparatus and dispersed throughout cytoplasm
51
What do Lysosomes do?
Contain acid hydrolases that destroy/digest unwanted substances (debris, bacteria) and damaged organelles
52
What do lysozymes do?
DO the actual foreign object destroying in lysosomes
53
What two important features do lysosomes have in the immune system?
Recognition and memory
54
What do peroxisomes do?
Use oxygen to inactivate H2O2
55
What is the cytoskeleton?
Filamentous structure that gives shape and stability to cell
56
What are the 4 types of filaments?
- Microfilaments
- Thick filaments
- Intermediate filaments
- Microtubules
57
What are microfilaments?
Actin; contractile protein found in all cells
58
What are thick filaments?
Myosin; found in conjunction with actin in muscle
59
What are intermediate filaments?
Filaments that help resist mechanical stress
60
What are microtubules?
Hollow tubes of tubulin, most rigid of filaments; found in elongated neural processes
61
What allows movement of molecules in cells?
Membranes and constituent proteins
62
What affects net flux (diffusion)?
- Temperature
- Mass of molecules
- Medium
- Surface area
63
What effect does mass have on diffusion?
Bigger molecules move slower
| Smaller molecules move faster
64
What effect does surface area have on diffusion?
More surface area= faster diffusion
65
What can limit movement of ions through a membrane due to its surface area?
Saturation of channels, transporters, etc
66
What effect does diffusion time have on molecule size?
Diff time= Distance^2, so molecules must be particular sizes to move fast enough and meet metabolic needs
67
What is the driving force behind molecular movement in and out of cells?
Concentration gradient
68
What is the driving force behind molecular movement within a cell?
Concentration gradients
69
What types of molecules easily cross membranes?
Water and lipid based molecules
70
What are the 4 ways polar and charged molecules can cross a membrane?
- Channels
- Mediated transport
- Osmosis
- Endo/exocytosis
71
What are channels?
Integral proteins that can open to allow through ions and charged particles, also have specificity
72
What is mediated transport?
Transporter proteins like revolving door for uncharged proteins (like insulin)
73
What openings allow osmosis to happen?
Aquaporins
74
What are endo and exocytosis?
- Endocytosis: membrane wraps around something and pulls it in
- Exocytosis: membrane releases things through vesicles
75
What do integral proteins allow to pass?
Ions and water
76
What does specificity in a channel mean?
It only lets through specific ions according to charge and size (Charged walls can push molecule out or let it in)
77
What are voltage gated channels?
Charge based channels that result in a conformational shift
78
Where are voltage gated channels found?
Neurons and muscle cells
79
What are ligand gated channels?
Opened by a particular substance such as hormones or Neurotransmitter
80
What are mechanosensitive channels?
Opened by stretching, pressure, basically any mechanical movement
81
What dictates movement of ions?
Electrochemical gradient
82
What is movement of ions a battle of?
Amount of ions vs charge
83
What is mediated transport used with?
Charged or polar molecules (proteins) that have no channels?
84
What are the two types of mediated transport?
Facilitated diffusion
| Active transport?
85
What is facilitated diffusion?
Movement from higher conc. to lower conc. (essentially same as regular diffusion, just through a pokeball looking protein)
86
What is active transport?
Pumps that consume energy to move molecules against the concentration gradient
87
Why is there a constant, intentional leak in Na/K and Ca pumps?
Body uses ATP to keep them stable, allows us to keep body warmth and makes us more aerobically oriented animals
88
What are the two types of active transport?
Primary active transport
| Secondary active transport
89
What happens in primary active transport?
ATP is used directly to move molecules against gradient through pump
90
What are the two types of secondary active transport?
Co-transport
| Counter-transport
91
What happens in Co-transport?
Molecules use energy and move in the same direction as another molecule, yet still against concentration gradient (Glucose and sodium an example)
92
What happens in counter-transport?
Molecules use energy and moves in the opposite direction of another molecules, yet still moves against the concentration gradient (Example is sodium and Calcium)
93
Can the number of transporters be changed?
Yes
94
Why is the number of transporters important?
It determines how fast molecules can move in or out of a cell (turnstile example)
95
What are the two methods of cell communication?
- Endocrine (hormone)
| - Synapses (electrical)
96
What direction does water always follow?
Water always follows the solute
97
How can movement of water be controlled in the body?
Only indirect control by movement of ions
98
What role do the walls of channels play in control of ion movement?
Lined with charge to attract or repel certain ions
99
What is osmosis?
Flux of water from an area of higher concentration to lower concentration
100
What is osmolarity?
[solute] of a solution within a liter of the solution
101
What is osmolality?
How much solute in a certain unit of solvent (kg of H2O)
102
1 osmole=?
1 mol of solute particles per unit solvent
103
1 mol NaCl in water = how many osmoles?
2 osmoles because 2 particles
104
What happens to volume when equilibrium is reached in a membrane that is permeable to solute and water?
No change in volume
105
What happens to volume when equilibrium is reached in a membrane that is impermeable to solute?
It will reach equilibrium but there will be a change in volume
106
What will happen to a compartment that remains constant in size while osmosis causes a change in volume inside?
Osmotic pressure
107
What is the typical osmolarity of extracellular and intracellular fluid?
300mOsm
108
What is the job of the renal system in relation to osmolarity?
Maintains isotonic osmolarity, no net flux one way or other
109
What does it mean if a extracellular solution is > 300 mOsm?
It is hypertonic and the cell will shrink
110
What does it mean if a extracellular solution is <300 mOsm?
It is hypotonic and the cell will swell
111
What happens in endocytosis?
Membrane invaginates to trap and ingest water or other particles
112
What happens in exocytosis?
Intracellular vesicles fuse with the cell membrane and extrude particles
113
How does the body maintain homeostasis?
Homeostatic control systems have a set point and expend energy to create a steady state and reach homeostasis faster
114
What is the difference between homeostasis and equilibrium?
Homeostasis uses energy
115
What are the 4 generalizations about homeostasis?
- Input=output
- Dependent upon balance of input and output, not magnitude
- Control systems cannot maintain complete consistency
- Each variable has a normal range of values
116
What kind of feedback system do virtually all homeostatic control systems use?
Negative feedback
117
What does negative feedback mean?
The feedback works against any disturbance to reverse it
118
What does positive feedback do?
Exacerbates disturbance, and would usually cause more harm than good
119
What is the farthest a cell will be located from a capillary?
50 um or no more than one cell away
120
How often does all the blood in the body traverse the entire system?
About once per minute
121
What are the main functions of the respiratory system?
Acquire O2, release CO2, and maintain pH through CO2 control
122
What buffers the bodys pH in the long run?
The renal system
123
What does the small intestine do?
Absorbs food and substrates
124
What are the functions of the GI system?
Absorb food substrates, release waste products
125
What are the functions of the hepatic system?
Degrades food substrates and helps store excess (glucose and glycogen)
126
What are the functions of the renal system?
Maintains homeostasis of water, ions, amino acids, and glucose
127
What happens to the blood if you drink too much water?
Hypotonicity
128
What are the functions of the nervous system?
Senses changes in external and internal environment and stimulates a proper response
129
What are the functions of the endocrine system?
Maintains homeostasis of food substrates, ions, temperature, etc; allows communication over long distances
130
How can a fever effect homeostasis set points?
Hypothalamus sets point higher, you feel colder and start sweating more, once immune system is done it returns to normal
131
What can acclimitization do to homeostasis set points?
- Heat: Lose less salts and more water sweating->hypertonic->thirst mechanism
- Cold: Increased BMR-> more cals burned-> more heat created
- Increased altitude: Breathe more often and deeper-> more red blood cells
132
What are circadian rhythms?
24 hour physiological cycles
133
When is growth hormone release?
Night
134
What drives circadian cycles?
Internal clocks such as pineal gland in hypothalamus, but receive info from external stimuli which can shift internal clock
135
What are circannual rhythms?
Yearly rhythms
136
What changes are seen in human circannual rhythms?
Mood changes due to melatonin, mating/hibernation
137
What is the main cause for change in circannual rhythms?
Changes in # of daylight hours
138
What is the path of the homeostatic reflex system?
1) stimulus-Afferent pathway
2) receptor- Hypothalamus
3) integrating center- efferent pathways
4) Effector- muscles/glands
5) response- negative feedback
139
What does neurotransmitter do?
Released by neuron to exert influence on effector
140
What are endocrine hormones?
Hormone released from gland into blood stream so it can be carried to activate other organs at a distance (requires receptors)
141
What are paracrine hormones?
Agent released by some cells/tissues and diffuse into extracellular (interstitial) fluid and interact via receptors with neighboring cells/tissue
142
What are autocrine hormones?
Agent released by cells/tissues have impact on same cells/tissues by interaction with membrane bound receptors
143
What are intracrine hormones?
Agent produced by cell interacts with receptors in that same cell
144
What are receptors named after?
What they bind
145
What are the 3 broad categories of receptors?
Steroid receptors
| Protein/peptide receptors
146
Where are steroid receptors found?
Intracellular
147
What part of the cell do steroids act on once they're bound?
Directly interact with DNA
148
Where are protein/peptide receptors found?
Bound to cell membrane because proteins cannot diffuse through
149
What features do protein/peptide receptors have?
- Specificity
- Affinity
- Saturability
150
What are spare receptors?
Empty receptors to increase the probability of binding
151
What happens to receptor reaction if its messenger increases or decreases in number?
- increased concentration = decreased sensitvity
| - Decreased concentration= increased sensetivity
152
What is signal transductions?
Method by which the intracellular biological activity of the intercellular messenger (1st messenger) is carried out within target cell
153
What is a 1st messenger?
Primary intercellular messenger
154
Which series of events following receptor activation is more complex?
That of membrane bound receptors
155
What are three examples of signal transduction mechanisms?
1) receptor complex incorporating ion channel (neurotransmitter)
2) Protein kinase-activated receptor acts as protein kinase that phosphorylates enzymes
3) G-proteins which is the most common mechanism
156
What do G proteins for primary messengers bind?
Guanine nucleotides
157
Where do secondary messengers do their work?
Inside the cell
158
What do G proteins as secondary messengers bind?
Adenylyl cyclase is effector protein
159
What do G proteins do as second messengers?
- Convert ATP to cAMP
- cAMP activates cAMP dependent protein kinases
- Initiates cascade of events, causing amplification
- Activity stopped by phosphodiesterase which breaks down cAMP
160
What are the two types of secondary messenger G proteins?
Gs or Gi
161
What can G protein secondary messengers do to membranes of organelles?
Activate their ion channels (Ca++)
162
What do G protein secondary messengers do when phospholipids bind to the membrane?
- Activates phospholipidase C (membrane bound enzyme)
| - Membrane phospholipid CPIP2 breaks down to IP3 and DAG
163
How does DAG act as secondary messengers?
DAG activates protein kinase C, which phosphorylates intracellular protein (enzyme
164
How does IP3 act as a secondary messenger?
IP3 causes release of intracellular Ca++ stored in ER, increases cytosolic Ca++ then acts to cause biological activity
165
How does Ca++ act as a secondary messenger?
(responds to chemical/electrical stimuli)
- Binds to calmodulin which activates calmodulin dependent protein kinases (indirect Ca++ activation)
- Activated kinases can phosphorylate other enzymes (Decrease or increase activity) which directly carry out biological activity
166
How does Ca++ work directly?
Can bind directly to certain enzymes to activate or inhibit them
167
What typically inactivates intracellular signal transduction?
Receptor inactivation, enzyme breaks down ligand bonded to receptor
168
What do all kinases do?
Break down ATP in order to phosphorylate
169
Can biological pathways work together?
No, they must all work independently
170
What is a nerve made up of?
Bundle of neurons
171
What are the 2 types of excitable cells that make up the neuromuscular system?
- Neuron
| - Muscle
172
What does a neuron typically consist of?
- Dendrites
- Cell body (soma)
- Axon (nerve fiber)
- Axon terminals
* *Axon hillock
173
What do dendrites do?
Receive info
174
What do neuronal soma do?
Carry out normal cellular activities
175
What do axons do?
Carry info towards other excitable cells
176
What do afferent axons do?
Bring info in
177
What do efferent axons do?
Take info away to bring about action
178
What do axon terminals do?
Transmit messages to other excitable cells
179
Which way do messages always move along axons?
Away from the point of initiation
180
What is conduction in the nervous system?
Message moving within the same neuron
181
What is transduction in the nervous system?
Message crosses a synapse to a target cell
182
What are the 3 types of neurons by structure?
- Multipolar
- Unipolar
- Bipolar
183
What are the 3 types of neurons according to function?
- Afferent
- Efferent
- Interneurons
184
Describe afferent neurons.
- Accepting
- Sensory
- Convey impulses to CNS
- No dendrites
- Only bipolar axons
- Soma lies outside of CNS
185
Through what part of the spine do afferent neurons receive info?
Dorsal part of spine
186
Describe efferent neurons.
- Effecting
- Motor
- Convey impulses towards PNS
- Has dendrites
- Soma is in CNS
187
Through what part of the spine do signals from efferent neurons leave?
Ventral part
188
Describe interneurons.
- Only in CNS
- Connect afferent and efferent neurons
- Make up 99% of CNS
- Help integrate and send out messages
189
What is a synapse?
Interface between one excitable cell and another
190
How do synapses stay on target?
Fibrous proteins tether pre and post synaptic cleft
191
Glial cells make up what percentage of the CNS?
90%
192
What do astrocytes (type of glial cell) do?
Substrate, ion, and spinal fluid control
193
What do oligodendrocytes (schwann cells) (type of glial cell) do?
Myelin production
194
What do microglia (type of glial cell) do?
Immune cells
195
What do ependymal cells (type of glial cell) do?
Structure formation
196
What is the brains constant goal with homeostasis?
Constant and total homeostasis
197
What is the resting membrane potential across neuron membranes?
Natural electrochemical potential across neuron membranes (~-70 mV)
198
What is in high concentration on the inside side of the membrane of a neuron?
- Nucleic acids (neg charge)
- Proteins (neg charge)
- Phosphates
- Sulfates
- K+ (charge of this overwhelmed by charge of everything else)
199
What is in high concentration on the outside side of the membrane of a neuron?
Cations
- Na+
- Ca++
200
How high is potential energy across a neuronal membrane?
Always very high, like a gun with the hammer cocked and ready to shoot
201
What determines RMP?
- Difference in intra vs extracellular concentration of ions
| - Permeability of membrane to specific ions
202
What is equilibrium potential (driving force) unique for?
- For each ion
| - For each cell
203
What are the 2 major ions that determine the change in membrane potential?
- Na+
| - K+
204
What is the extracellular concentration of Na?
145
205
What is the intracellular concentration of Na?
15
206
What is the extracellular concentration of Ca?
100
207
What is the intracellular concentration of Ca?
7
208
What is the Extracellular concentration of K?
5
209
What is the intracellular concentration of K?
150
210
Why is Ca not a bigger player in propagation of action potential?
Not many gates to let it in, so they are saturated more easily
211
What is the equilibrium potential for K?
-90mV
212
What is the equilibrium potential for Na?
+60mV
213
What is the RMP for a regular membrane?
-70mV
214
Why is RMP for regular membrane so low compared to the two equilibrium potentials of Na and K?
1. Differences in membrane permeability; K is leakier, which uses up about 40% of bodies ATP at rest
2. Na/K pump is electrogenic and contributes -4mV charge to RMP
215
What does it mean that the membrane at rest is "polarized"?
Separated by charge, so energized
216
What does the Na/K pump do?
Utilizes ATP through an ATPase to move 3 Na out and 2 K in
217
How is membrane potential changed?
By changing the permeability of the membrane
218
What causes the opening of ligand gated channels in graded potential?
Neurotransmitter
219
What are some characteristics of graded potential?
- Slow change in mem. pot.
- Change in potential (current) restricted to small area
- Intensity of graded potential= intensity of stimulation
- As current diffuses away from site of initiation, its intensity decreases
220
What does depolarization mean?
Becoming more positive which is better for activation
221
What does hyperpolarization mean?
Becoming more negative, which will inhibit activation
222
What opens channels in action potential?
Voltage
223
What are some characteristics of action potentials?
- Changes in mem. pot. fast but brief
- "all or none" principle
- Self propagating
224
Through what mechanism are electrical impulses typically conducted over long distances?
Action potential
225
What happens when a membrane depolarizes to -55mV in AP?
Voltage gated Na Channels are opened (permeability increased 5000x), which results in depol which brings charge to +30 mV
226
What brings the charge back down in AP?
Voltage gated slow K channels bring the charge back down through eflux of positive charge
227
What is an absolute refractory period?
Period where no matter what an AP won't propagate again
228
What is a relative refractory period?
Period where a strong enough charge can cause another AP
229
What pumps are always working to re-establish proper distribution of ions across a membrane?
Na/K pump
230
When depolarization happens, where does it happen?
Only across the membrane, very localized
231
What amount of ions have to move to cause an AP?
a very small amount
232
What do APs work with to stimulate their firing?
Graded potentials
233
Where is the first place voltage gated channels are located?
On the axon hillock
234
Which way does the current generated by AP travel?
Along membrane away from point of initiation
235
What determines speed of impulse conduction in AP?
Thickness of axon and myelination
236
Why is the myelin sheath regularly interrupted?
To expose the nodes of ranvier where a new AP can be generated which re-increases the intensity and keep moving down the line
237
What is saltatory conduction?
The AP jumps from node of ranvier to node of ranvier all the way to the nerve terminal
238
At what speeds do action potentials move?
Huge range, some at 300mph, some at 4-5 mph
239
What are the 2 basic steps of AP?
- Na+ influx
| - K+ eflux
240
What does all repolarization rely on?
K+ eflux
241
What determines the highest speed?
The highest input resistance, rather than longitudinal resistance, input resistance prevents the AP from penetrating the cell and losing its momentum
242
What are the 2 basic types of synaptic transmission cells?
Electrical
| Chemical
243
How are electrical synaptic transmission cells connected?
Joined together by gap junctions (uncommon in nervous system)
244
How are chemical synaptic transmission cells connected?
Substance near transmitter is released from terminal of pre-synaptic neuron and binds to post-synaptic cell
245
What is the mechanism for synaptic transmission?
- AP reaches axon terminal and opens voltage gated Ca++ channels (no myelination at terminals)
- Ca++ enters terminal
- Neurotransmitter bound in vesicles released via exocytosis
- Causes local graded potential of post-synaptic membrane
246
What kind of effect does excitatory post-synaptic potential (EPSP) have?
Depolarizing effect
247
What kind of effect does inhibitory post-synaptic potential (IPSP) have?
Hyperpolarizing effect
248
What is the RMP for synaptic transmission cells?
-55mV
249
What causes the Ca++ release in synaptic transmission cells?
Neurotransmitter
250
How do EPSP cause an AP?
1. temporal summation- several EPSPs delivered in quick succession from single pre-synaptic neuron
2. Spatial summation: several EPSPs from several different pre-synaptic neurons arrive simultaneously
251
What is an exception to the normal amount of EPSPs it takes to cause an AP?
Endplate potential of peripheral nervous system (neuromuscular junction) is an exception where the EPSP is overkill and about 20x stronger
252
Why is the resting potential in pacemaker cells less than that of other neurons (about -55mV)?
due to the greater permeability (leakiness) (cardiocytes) of Na+ of those membranes
253
What types of cells mostly have a pacemaker potential?
Smooth muscle cells and myocardium
254
What causes depol in pacemaker cells to threshold voltage?
Leakiness of Na+ (Ca++ in smooth muscle) brings it from -55mV to -40mV
255
What are the steps of pacemaker depol?
- Na+ leakiness brings from -55mV to -40mV
- Voltage gated fast Na+ channels open
- Voltage gated slow Ca++ channels open and K+ channels open to cause a plateau
- K+ channel stays open and causes repol.
- K+ channels close and process repeats itself
256
What is happening with blood in the plateau phase of pacemaker potential?
Heart is filling with blood
257
What are the 3 major brain levels by evolutionary basis?
1. Spinal cord
2. Lower brain
3. Upper brain
258
What does the spinal cord do?
- conduit for signals to and from the brain
- Has neuronal circuits in it that can control
a) walking movements
b) quick reflex to pain movements
c) posture reflexes
d) Local blood vessel control reflexes
e) GI movement reflexes
259
What makes up the lower brain?
- Medulla
- Pons
- Cerebellum
- Hypothalamus
- Thalamus
260
What does the lower brain do?
Control subconscious body functions like
- Arterial pressure and respiration (medulla and pons)
- Equilibrium and balance (Cerebellum and medulla)
- Feeding reflexes (Medulla, pons, and hypothalamus)
- Emotions
261
What part of the lower brain is responsible for fine motor motion?
Cerebellum
262
What does the higher brain always have to work with?
The lower centers of CNS
263
What does the higher brain do?
- High tunes functions of lower brain
- Acts as memory storehouse
- Center of higher thought processes and imagination/creativity
* limbic system that can tie senses with emotions
264
What are the two divisions of the peripheral nervous system?
- Afferent which conveys info from peripheral receptors to CNS
- Efferent which carries signals from CNS to muscles or glands
265
What are the two divisions of the efferent nervous system?
- Somatic (voluntary) which controls skeletal muscle
| - Autonomic (involuntary) which controls things like smooth muscle, cardiac muscle, etc
266
What type of neurotransmitter is used in the somatic division of the efferent nervous system?
Only excitatory signals with Ach
267
Where is the cell body for the somatic division of the efferent system located?
In the CNS
268
How many neurons does the somatic nervous system involve?
one that uses Ach pre-ganglionic and at the end
269
How many neurons does the autonomic nervous system involve?
Two, which uses Ach pre-ganglionic and uses it post-ganglionic if it is calm, if not it uses norepi
270
Where is the autonomic ganglion located?
Outside CNS
271
From where do the sympathetic branch nerves leave?
Thoracic and lumbar
272
What are the two subdivisions of the autonomic nervous system?
- Sympathetic
| - Parasympathetic
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What is the post-ganglionic NT in the sympathetic nervous system?
Norepinephrine, which stimulates fight or flight
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What are the adrenal medulla?
Specialized autonomic ganglion
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From where do the parasympathetic branch nerves leave?
Cervical and sacral regions
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What is the post-ganglionic NT in the parasympathetic nervous system?
Ach
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Where is most neuronal info from the parasympathetic nervous system passed through?
Two vagus nerves to thoracic and abdominal regions
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What kinds of effects do both sympathetic and parasympathetic nervous systems have?
Both excitatory and inhibitory
| Ex: Parasympathetic increases GI activity, but decreases heart activity
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What makes the blood brain barrier so tight?
Endothelial cells joined together by tight junctions
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What is cerebrospinal fluid?
Fluid made in and fills ventricles of brain for protection
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What does the cerebrospinal fluid bathe?
Exterior of brain and spinal cord
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What is hydrocephalus?
Accumulation of Cerebrospinal fluid
