Term
| Four Kinds of Glial Cells |
|
Definition
| Astrocytes (most abundant), Oligodendrocytes, Microglia, Ependymal Cells (have cilia) |
|
|
Term
|
Definition
1. Physically support neurons in spacial relationships
2. Serve as scaffold during fetal brain development
3. Induce formation of blood/brain barrier
4. Help transfer nutrients to neurons
5. Form neural scar tissue
6. Take up and degrade released neurotransmitters
7. Take up excess K+ to maintain proper brain-ECF ion concentration and normal neuron excitability
8. Enhance synapse formation and strengthen synaptic transmission via chemical signaling with neurons
9. Communicate via chemical means w/ neurons and among themselves |
|
|
Term
|
Definition
| Form myelin sheaths in CNS |
|
|
Term
|
Definition
1. Role in defense of brain as phagocytic scavengers
2. Release nerve growth factor |
|
|
Term
|
Definition
1. Line internal cavities of brain and spinal cord.
2. Contribute to formation of cerebrospinal fluid.
3. Serve as neural stem cells with the potential to form new neurons and glial cells. |
|
|
Term
|
Definition
| large protein secreted by astrocytes that can trigger synapse formation. |
|
|
Term
|
Definition
| Brain tumors of neural origin usually consist mostly of glia, and are called this. |
|
|
Term
| Possible Functions of Voltage-gated Na+ Channels in Glial cells |
|
Definition
1. Synthesize the channels to donate them to neighboring neurons, decreasing the biosynthetic load on the neurons.
2. Endow glial cells with electrosensory functions that allow them to better communicate with neighboring neurons
3. Possibly used to fuel Na/K ATPase pump, facilitating and modulating K+ uptake from the ECF |
|
|
Term
|
Definition
| internal milieu, regulate internal environment within narrow range |
|
|
Term
|
Definition
| organization of cells, tissues, organs is designed to maintain “homeostasis” (coined term) |
|
|
Term
| Variables Regulated for Homeostasis of ECF |
|
Definition
1. Water, salt, electrolytes
2. Nutrient molecules (glucose)
3. O2 & CO2
4. Waste products
5. pH
6. Volume & pressure
7. Temp |
|
|
Term
|
Definition
|
|
Term
|
Definition
in ECF: Cl-, HCO3-
in ICF: PO4^2-, protein anions |
|
|
Term
| Components of a Negative Feedback System |
|
Definition
| Sensor, Control Center, Effector |
|
|
Term
| Stroke Volume; Intrinsic and Extrinsic Controls |
|
Definition
Intrinsic: stretch of heart muscle affecting stroke volume
Extrinsic: neuronal control of stroke volume |
|
|
Term
|
Definition
| Increased inward Na+ current, Decrease outward K+ current, Increased inward Ca2+ current |
|
|
Term
| Properties of Cardiac Cells |
|
Definition
1. Inherent rhythmicity
2. Excitability
3. Conductivity
4. Contractility |
|
|
Term
| Nervous System Influence on Heart Rate |
|
Definition
| Sympathetic stimulation speeds it up, Parasympathetic slows it down |
|
|
Term
|
Definition
| Period of time when heart is in contraction (1/3 of time at rest) |
|
|
Term
|
Definition
| Period of time heart is relaxed (2/3 of time at rest) |
|
|
Term
|
Definition
| Volume of blood pumped per contraction (per heart beat) |
|
|
Term
| End Diastolic Volume (EDV) |
|
Definition
| Volume of blood in ventricle before contraction |
|
|
Term
| End systolic volume (ESV) |
|
Definition
| Volume of blood in ventricle AFTER contraction |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Total Cardiac Output = Heart Rate x Stroke Volume |
|
|
Term
|
Definition
| Peak pressure exerted by ejected blood against vessel walls during cardiac systole. Averages ~ 120 mmHg |
|
|
Term
|
Definition
| Minimum pressure in arteries when blood is draining off into vessels downstream. Averages ~ 80 mmHg |
|
|
Term
| Mean Average Arterial Pressure |
|
Definition
| [(Pd x td) + (Rz + ts)] / td + ts |
|
|
Term
|
Definition
Blood Flow (Q) = dP x (pi x r^4)/(8 x L x h)
Where:
dP = Change in pressure
r = radius of vessel
L = length of vessel
h (eta) = viscosity of fluid |
|
|
Term
| Causes of Vasoconstriction |
|
Definition
| Increase in myogenic activity, increase in oxygen, decrease in CO2 and other metabolites, , increase in endothelin, increased sympathetic stimulation, vasopressin, angiotensin II, cold temperatures |
|
|
Term
|
Definition
| Decrease in mygogentic activity, decrease in oxygen, increase in CO2 and other metabolities, increase in nitric oxide, increase in prostacyclin, decrease in sympathetic stimulation, release of histamine, hot temperatures |
|
|
