Exam One Study Questions Flashcards
What is the major organizational plan of the body?
cells —> tissues —> organs —> systems
What are the four primary tissues?
connective, epithelial, muscle, and nervous
Delineate between the three types of muscles.
Skeletal: voluntary, striated, myofibers. grated contractions, tendons and bones
Cardiac: involuntary, striated, intercalated disks, who heart contraction, heart
Smooth: involuntary, no striating, functional syncytium, whole contraction, digestive, lungs, blood vessels, reproduction
What is the substructure of the neuron?
Soma: cell body
Dendrites: receive signals
Axon: delivers signals
Nodes of Ranvier: spaces between myelin cells
Myelin sheaths
Axon hillock
Anatomical classifications of epithelial tissues and their two main functions are?
squamous epithelial: cheeks, capillaries, lungs
cuboidal: reproductive tract, kidney, pancreas
columnar/ciliated columnar: uterine tubes, reproduction, reproduction, respiratory cilia
Two primary functions:
(1) membranes: rigid, junctional complexes, basement membranes
(2) glands: exocrine and endocrine
What are the four types of connective tissue?
Proper - skin, space between cells
(a) loose: collagen fibers, spaces nerves/blood vessels
(b) dense: packed collagen, tendons move to bone
Cartilage - chondrocytes, precursor to bone
Bone - haversian system, osteoblasts
Blood - plasma
What is ICF?
Intracellular fluid, the fluid INSIDE CELLS
What is ECF?
Extracellular fluid, the fluid OUTSIDE CELLS, aka plasma and interstitial fluid
Plasma
part of the ECF, fluid portion of the blood
interstitial fluid
surrounds and bathes cells, part of the ECF
Organelles structure and function
See notes for full answer
How is the structure of the phospholipid bilayer important to physiological functions?
very important for the generation of electrical signals, it acts as a capacitor
allows for the formation of concentration gradients
protects cells from potentially harmful molecules
Identify the functions of specialized proteins in the latticework.
integral proteins: embedded in the lipid bilayer
transmembrane proteins: extend through the entire thickness of the membrane
peripheral proteins: polar molecules that do not penetrate the membrane, but instead stud the surface
Review of GENERAL principles of glycolysis, TCA, and electron transport chain.
Glycolysis: anaerobic, break down of glucose into pyruvate, net production of 2 ATP and 1 NADH
TCA: facilitates recycling pathways and nitrogen trafficking necessary for catabolism, also influences redox state and oxidative capacity
ETC: a series of redox reactions that relies on protein complexes to transfer electrons from a donor molecule to acceptor molecule (proton gradient to form ATP)
Cellular activities that require energy expenditure are?
Active transport, exocytosis, endocytosis, synthesis of ATP
How does the Chemiosmotic Hypothesis demonstrate several classic physiological principles?
How are organic molecules classified?
What is the structure of protiens?
Long chains of amino acids forming peptide bonds
What is the major function of nucleic acids?
storage of genetic information
Review the genetic code, transcription, translation.
How are molecules transported across and through the membrane?
Multiple types of transport: active vs. passive
Assisted - carrier mediated, vesicular
Carrier Mediated - facilitated diffusion, active transport
Vesicular - endo and exocytosis
Passive - diffusion of small molecules unaided through the membrane
pinocytosis
non selective uptake of ECF
receptor mediated endocytosis
selective uptake of large molecules
phagocytosis
selective uptake of a multimolecular particle
transcytosis
shuttle large intact molecules through the cell
What type of membrane transport requires energy?
active transport, endo and exocytosis
What membrane transport requires proteins?
osmosis, facilitated diffusion, active transport
What type of membrane transport requires a gradient?
simple diffusion, secondary active transport
Name physiological mechanisms where transport is operational.
- Osmosis - movement of water through diffusion
- Na/K pump - primary active transport
- Na/K channels - secondary active transport
How does Einstein’s Random Walk Theory relate to synaptic transmission?
Synaptic transmission has to do with diffusion of neurotransmitters through the synaptic cleft, which related to Einstein’s Random Walk Theory because molecules move around to fit a space, via diffusion.
How do concentration gradients, size of NT, charge, and temp affect the rate of electronic signaling?
The steeper the gradient, the faster the signals will travel.
The larger the NT, the slower the diffusion of the NT will be.
Charged molecules change diffusion rates.
Increase in temperature will increase diffusion.
What are rbcs natural osmometers?
The cells will increase in size (lyse) when in a hypotonic solution with respect to the cell, and will shrink (crenate) when in a hypertonic solution. RBC isotonic osmolarity = 300 mOsm
What are distinct characteristics of only protein mediated transport?
- transport with proteins is faster than simple diffusion
- exhibits stereospecificity for molecules and will compete for structurally similar molecules
- saturation kinetics = sigmoid property
What does primary active transport have to do with phosphorylation?
Primary active transport requires the use of ATP, where the phosphate group is removed to produce energy. This phosphorylation of the molecule releases ADP and changes the conformation of the protein.
What are the generic regions of specialization for a “typical” nerve cell?
Dendrites: receive info
Soma: cell body
Axon hillock: action potential origin
Axon: sends signals
Where are the anatomically distinct neuron types located in the body?
pseudounipolar: tactile receptors
bipolar: sensory neurons, rods of retina
multipolar: most common, highly integrative, motor neuron
What physiological processes are in common for all neuron types?
impulse conduction, cell-cell communication, respond to stimuli
Do all cells that have a negative resting potential have a capacity to fire an action potential? Why or why not?
Not all cells can fire an action potential because not all cells have the ability to reach a threshold to fire an action potential.
In what form is information encoded in the nervous system?
Electrical impulses in the form of action potentials
How does changing the action potential shape change the information?
frequencies and durations provide certain info for the NS. (????)
If you were to block certain ionic conductances underlying the action potential with drugs, how would various scenarios alter the encoded information?
…
What is absolute and relative refraction?
absolute refractory: the period of time in which a neuron cannot be excited by a secondary stimulus
relative refractory: the period of time in which a neuron can be excited after firing an AP, but the stimulus must be stronger than usual
What type of ion channel blockers would affect rates of action potential firing?
sodium channel ion blockers would cause the cell to not be able to depolarize to reach threshold
Why do we clinically want to measure ion channel physiology?
For diseases and drug effectiveness
What are classic principles of action potentials?
All-or-none: there can only be an action potential when threshold is reached
How are local currents distinct from action potentials?
Local currents are initiated by graded depolarization of the axon hillock.
Action potentials are not graded because of the all-or-none principle.
Action potentials are typically not located in areas of excitable cells where graded potentials take place because of the sparsity of Na+ channels.
If local currents are decrementing, what is their physiological function?
The neutralize or eliminate some of the unbalanced charges in the inactive areas, which can bring an inactive area to threshold
Does the all-or-none principle contradict the theory of recruitment?
No, the Theory of recruitment has to do with adding action potentials to generate enough voltage to reach the threshold for another action potential. Each much still reach its own threshold.
Do all nerve cells have the same threshold and space constant? Why or why not?
No, each can have different thresholds and space constants because of the diversity of ion channels in the membrane.
What is a myelinated axon?
The type of axon that increases resistance and velocity of a current by insulation.
How does saltatory conduction velocity assist the nervous system in terms of energy, space, and speed?
It decreases the amount of energy, increases the speed through the insulation of myelin sheaths. This allows the AP to go further before having to refire, where they do so in the Nodes of Ranvier.
What is the physiological basis for Multiple Sclerosis?
There is a reduction in conduction velocity, or an alteration. Fibers don’t conduct properly, causing a lack of coordination or spasticity in muscle contraction. The body’s antibodies attack myelin, causing scar formation of the myelin and axon.
Do Schwann cells or oligodendrocytes assist in regeneration?
Schwann cells assist in regeneration
Compare and contrast electrical synapses with the traditional chemical synapse.
Both carry information from a pre to post-synaptic cells.
Electrical: no synaptic delay, use gap junctions with 2 connexons that twist to open. useful in reflex pathways and synchronization in smooth muscle, cardiac cells, and epithelial cells
Chemical: slower, rely on simple diffusion of neurotransmitter in the synaptic cleft. operates at nerve terminals that broaden into specialized regions (terminal butons).
How do microtubules assist in synaptic transmission?
They help bring down neurotransmitters into the terminal butons with anterograde transport and kinesin. retrograde transport of NTs is assisted by dyenine on microtubules.
If you had a drug that blocked (ligand gated ion channels, presynaptic uptake, phosphorylation, AChE, anterograde transport) how would taking this “prescription” affect the excitability of your muscle?
What are the properties of neuroglia?
Serve as connective tissue, support, and balance electrolytes and ions
What are the four classes of neuroglia?
- astrocytes
- oligodendrocytes
- epedymal cells
- microglia
What other factors could induce similar patient symptoms as Multiple Sclerosis?
Lead, tin, and cleaners can damage myelin
What class of neuroglia is important during a stroke? Why?
Astrocytes, they take up excess neurotransmitters
What class of neuroglia is protective against brain damage?
Epedymal
Which class of neuroglia assists to increase the conduction velocity of nerve impulses?
oligodendrocytes
Which class of neuroglia assists in immune response?
microglia
What are some clinical causes of brain damage?
- aggressive shaking/jarring
- oxygen deprivation
- CVA (stroke)
- brain tumors (glioma)
What are the physiological mechanisms underlying a cerebrovascular accident?
Rupture or blockage of cerebral blood vessels, therefore blockage of glucose and O2 leading to massive neuronal death with motor and memory loss.
What are some new treatments to prevent further neuronal cell death?
- administer drugs - anticoagulants (dilute excess NT)
- 2 hour window - blocker of glutamate-R (dampens excitotoxicity)
Know the structure and function of the major brain regions, what common diseases are associated with each?
What are some modern technical devices used to detect brain tumor and what are their principles of operation?
CAT: computerized axial tomography, x-rays and computer tech create 3D sections of brain
MRI: magnetic resonance imaging, generates magnetic fields and signals generated from brain structure depends on tissue composition
What is plasticity?
The ability to change or be functionally remodeled in response to the demands placed on it
How is plasticity related to use-dependent competition for cortical space?
Brains are subject to constant subtle modifications based on use and the architecture of the brain can be influenced.
What are some selective language disturbances that occur due to stroke or genetic defects?
Broca’s area: affecting expression
Wernicke’s area: affecting comprehension
How does the homunculus cartoon graphically represent our perceived input at responsive motor output? How does it demonstrate the somatotopic map?
Represents the motor outputs to different parts of the body and sensory inputs to the cortex from different parts of the body
It’s an unequal graphic representation proportional to the relative input and output coded upside down and receives input from the opposite side
What cell type does Parkinson’s disease target?
DA neurons
What are some clinical symptoms, cellular causes and mechanisms of Parkinson’s?
Early symptoms: involuntary shaking, tremors
Later symptoms: loss of speech inflection, stooped gate/shuffling
Final symptoms: memory/thinking impairments, difficulty swallowing
Cellular Causes: Lack of dopamine inhibitory response from the basal nuclei, preventing smooth movements
How does Parkinson’s relate to Schizophrenia?
Parkinson’s is a lack of the inhibitory response of dopamine, while Schizophrenia is an overabundance of the inhibitory response of dopamine.
What cell type does Alzheimer’s target?
cholinergic neurons in the hippocampus
What are some clinical symptoms of Alzheimer’s?
Confusion, disorientation, personality changes, emotional outbursts
What are the cellular causes of of Alzheimer’s?
A loss of ACh in the amygdala, hippocampus, and temporal lobes
How is Alzheimer’s associated with a metal?
Neurofibrillary tangles form as axons and dendrites degenerate. In the middle of this tangle is a paque of aluminum.
What is the reticular formation? How does it relate to your alertness?
The reticular formation is an interconnection throughout the brain that provides a degree of arousal/alertness.
How can we measure alertness and what is this electrical signal?
We measure alertness through EPSPs and IPSPs, brain waves are used to detect the health of the brain and the degree of state
What are the levels of consciousness?
- maximum alertness
- wakefulness
- sleep stages
- coma
What is electrocerebral silence?
A completely flat EEG, no brain activity AT ALL, no EPSPs or IPSPs.
Describe why sleep is an active process.
Sleep is an active process as we are constantly going through cycles of sleep, from slow wave sleep to paradoxical sleep and back again. We use large amounts of O2 and it is essential for learning
What is slow wave sleep?
Characterized by slow, high amplitude, delta waves. There are four stages in which you cycle through as follows: 1-2-3-4-3-2-1 before entering into paradoxical sleep.
What is paradoxical sleep?
Characterized by brain waves similar to those when we are awake, these are called beta waves.
