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Human Physiology Exam 1 Study Guide:
1. What is the major organizational plan of the body? And what are the four primary tissues?
Cells tissueorgansorgan system
2. Delineate between the 3 types of muscle (skeletal, cardiac, and smooth)?
Smooth: they are elongated and spindle shaped, and they are commonly involved with involuntary movement (walls of blood vessels, bladder, digestion)
Skeletal: they are made up of cylindrical fibers and are attached to the muscles in the body, they are involved with voluntary movement Cardiac: these cells are quadrangular in shape and form a network of fibers. These muscles are involuntary and are found in the heart
3. What is the substructure of the neuron (functional unit of the nervous system)?
Cell body: holds the nucleus and most of the organelles
Dendrites: extensions of the neuron which receives signals from other cells Axon: part of cell that extends from cell body and uses action potential to send signals
Axon terminals: where the neuron sends neurotransmitters into the synapse into another neighboring cell If you want to learn more check out What is the meaning of Bond energy?
If you want to learn more check out What are Metabolic Pathways?
4. Anatomical classifications of epithelial tissue and 2 primary functions?
1. secrete and absorb mucus and enzymes
2. protect against abrasion
5. Four types of connective tissue?
-connective tissue proper (covers skin)
6. Distinguish between ICF, ECF, plasma, and interstitial fluid? ICF: fluid inside the cells themselves Don't forget about the age old question of Who discovered the electrical force equation was very similar to the force equation?
Plasma: greyish-yellow protein containing fluid portion of the blood where rbc’s and platelets are suspended (surrounds ISF)
ISF: fluid that bathes most tissues, not including the fluid in the lymph and blood vessels
ECF: ISF + plasma
7. Organelle structure and function?
Nucleus: contains the cells genetic material and is where ribosome production takes place, the inside is a dense structure called the nucleolus that is surrounded by a nuclear envelope
Endoplasmic Reticulum: It is composed of the smooth ER and the rough ER, it transports the proteins that are synthesized by the ribosomes, and the smooth ER synthesizes lipids Don't forget about the age old question of what are the Main effects and interactions?
Golgi Apparatus: it is a stack of membrane bound flattened stacks and it modifies the proteins it receives from the ER; it puts them in vesicles so they may be transferred around the cell We also discuss several other topics like Components of Globalization
Mitochondria: they are round and membrane bound and they perform aerobic respiration, they are the source of ATP production in the cell Lysosomes: they are membrane sacks that contain digestive enzymes to break down materials
Ribosomes: small organelles composed of two subunits that synthesize proteins and translate genetic material into mRNA
8. How is the structure of the phospholipid bilayer important to physiological
∙ Selectively permeable so it can choose what it wants to allow into the cell
∙ 100x the volume of the cell passes through every second so it must be very selective about what it lets in
∙ Barrier for water soluble molecules
∙ Has proteins in a sea of fat that allow cell-cell communication, allow facilitated diffusion, and also important to extracellular molecule recognition
∙ Maintains the cell’s cytoplasmic concentrations, osmolality, and pH
9. Identity and functions of specialized proteins in the latticework? Membrane receptor: protein that relays signals between a cells internal and external environment
Transport protein: moves ions and molecules across the membrane Cell adhesion molecule: allows cells to recognize and interact with one another
Membrane enzymes: performs various activities such as transferase and hydrolase Don't forget about the age old question of What makes humans unique from other species?
10. Review of GENERAL principles of glycolysis, TCA, electron transport chain?
Glycolysis: a metabolic pathway that converts glucose into pyruvate giving off ATP and NADH, first process of cellular respiration (produces 2 ATP) TCA: a serious of chemical reactions that generates energy by oxidizing Acetyl-CoA, second process of cellular respiration (produces 2 ATP) Electron Transport Chain: there is a series of electron acceptors in donors where the transfer of electrons creates energy, this is called oxidative phosphorylation. It is the final stage of cellular respiration and creates the most ATP (produces 34 ATP)
11. Cellular activities that require energy expenditure? -folding of proteins
-pumping protons and ions across the cell membrane
-constricting muscles motor proteins
-forming vesicles to transport materials across the cell
-protein and nucleic acid synthesis
12. How does the Chemiosmotic Hypothesis demonstrate several classic
It is simply ions moving down their concentration gradient, and it more specifically relates to the generation of ATP synthesis. It states that molecules such as glucose are metabolized into energy rich intermediates like Acetyl-CoA. After this protons flow into the mitochondrial matrix which provides enough energy via the Proton Motive Force to turn ADP into ATP. This process successfully demonstrates diffusion by the transferring of molecules from a high gradient to a low one, and also electrostatic force as protons diffuse down the electric potential
13. How are organic molecules classified?
They are classified based on which functional group they belong too
14. What is the structure of proteins?
Primary: linear arrangement of amino acids
Secondary: there is folding and coiling caused by hydrogen bonding, there are alpha helixes and beta sheets
Tertiary: 3D structure of protein which happens from non-covalent interactions between amino acids
Quaternary: this is a large single protein formed when multiple polypeptide chains bond (EX: hemoglobin)
15. What is the major function of nucleic acids?
They make of the genetic information of living things (DNA & RNA)
16. Review the genetic code, transcription, and translation? Genetic code: triplets of DNA and RNA that carry genetic information (codons)
Transcription: when DNA is copied into mRNA by RNA polymerase Translation: when mRNA is decoded by a ribosome into a specific amino acid chain
Replication transcription translation
18. How are molecules transported across and through the membrane?
-fusion of vesicles
-protein mediated transport mechanisms
19. Which types of membrane transport requires energy? requires proteins?
requires a gradient? Name physiological mechanisms where transport is operational?
Endocytosis: requires ATP, requires fusion of vesicles
Exocytosis: requires ATP, requires fusion of vesicles, reverse of endocytosis -secretion of enzymes
-release of neurotransmitters
Simple Diffusion: does not require ATP or proteins, requires a gradient -things like O2 can diffuse right through membrane
Osmosis: does not require ATP or proteins, requires a gradient -allows water to diffuse in and out of cell
Facilitated Diffusion: does not require ATP, requires proteins and a gradient -moving K+ into cell with a channel protein
Primary Active Transport: requires ATP and proteins
Secondary Active Transport: requires proteins, and an electrochemical potential difference
-co-transporters (symport & antiport)
20. How does Einstein's Random Walk Theory relate to synaptic transmission?
His theory relates to Brownian movement of particles and it says molecules will move until dynamic equilibrium is reached, a neurotransmitter is released from a pre-synaptic vesicle and it then diffuses to the post-synaptic vesicle
21. How do concentration gradients, size of NT, charge, and temperature
affect the rate of electronic signaling?
Size: as size increases, rate decreases
Charge: as charge increases, rate decreases
Temperature: as temperature increases, rate increases
22. Why are rbcs natural osmometers?
Since they have a semi-permeable membrane they react to what solution they are in. They will be normal if the solution is isotonic, they will crenate (shrink) if the solution is hypertonic, and they will lyse if the solution is hypotonic. Since they react to the environment this way by simply observing what they look like they are very good osmometers
23. What are distinct characteristics of only protein-mediated transport?
∙ Faster transport than diffusion
∙ ATP is required
∙ Proteins have steriospecifity for certain molecules
∙ Saturation kinetics
24. What does primary active transport have to do with phosphorylation?
Using ATP to transfer a phosphate to an amino acid causes a conformational change to the compound being transported
25. What are the generic regions of specialization for a "typical" nerve cell
and where are the anatomically distinct neuron types located in the body?
∙ input (dendrites: receive incoming information)
∙ trigger zone (axon hillock: initiates AP)
∙ conducting (axon: conducts AP continuously)
∙ output (axon terminals: releases NT to effector cells)
1. bipolar: PNS & sensory organs
2. pseudounipolar: touch receptors
3. unipolar: CNS
4. multipolar: motor neurons
26. What physiological processes are in common for all neuron types?
∙ Information is passed along in the form of an action potential ∙ Conduction is unidirectional
∙ Na/K ATPase pump sequesters K+ inside and shoots Na outside ∙ Charged ions are polar and have poor permeability so they will flow down the concentration gradient using facilitated diffusion ∙ Pump ions against concentration gradient, then a stimulus opens the gate of respective ion channels and the ions will flow down the concentration gradient= action potential!
27. Do all cells that have a negative resting potential have the capacity to fire an action potential? Why or why not? No, they must have an action potential of at least -50 to -60 mV difference to generate an action potential
28. In what form is information encoded in the nervous system? How does
changing the action potential shape change the information? If you were to block
certain ionic conductances underlying the action potential with drugs, how
would various scenarios alter the encoded information? There are various ions in the neuron (Na,K,Ca,etc.) that cause a voltage gradient across the membrane, when the voltage changes drastically that creates an action potential which is a nerve impulse. If you increase the length constant, then you increase the conduction velocity of the action potential. If the drugs blocked the Na+ channel, then the action potential would not fire. If they blocked the K+ channel the width of the action potential would increase
29. What is absolute and relative refraction; what type of ion channel blockers
(drug targets) would affect rates of action potential firing? Absolute refraction: when one part of the membrane has just undergone an action potential and is unable to fire another
Relative refraction: the potential can be re-stimulated by a stronger stimulus, the K+ channels are still open
- TTX (tetrodotoxin) blocks Na+ gates
- Botulinus toxin & procaine inhibit release of neurotransmitters and Ca2+ channels
- Atropine, curane, TTX, nicotine, and alpha-bungaratoxin destroy neurotransmitters completely, and block binding of neurotransmitters by competitive inhibition
- Strychnine, nerve gas, picro toxin, caffeine, theophylline, parathion, and malthion make it so Ach (acetylcholine) is not able to break down so the nerve continues to fire
- Cocaine and Adderall inhibit the reuptake of Ach
30. Why do we clinically want to measure ion channel physiology? -It helps us prevent disease
-open heart surgery
-helps with cystic fibrosis & seizures
32. What are the classic principles of the action potential? 1. Rapid change in membrane potential
3. Threshold is 15% amplitude
4. Not all cells are electrically excitable to fire AP
5. Moves unidirectional down axon to the terminal (due to Na channel rapid inactivation)
6. Non-decremental propagation
33. How are local currents distinct from action potentials? If the former are
decrementing, what is their physiological function?
Local currents decay while action potentials do not. Local currents are caused by an influx of Na+ ions, local currents then cause depolarization of the adjacent membrane in the opposite direction of the action potential. This causes local currents to trigger an action potential there so they act as a stimulus
34. Does the ALL-or-NONE principle contradict the theory of recruitment?
In some ways it does, but you still need a stimulus to activate the motor neuron. The theory of recruitment is the idea that a stronger stimulus will in turn activate more muscle fibers which leads to a stronger contraction. These deposits fill with fat as we get older which is why we can still fire off the motor neurons but the overall contraction is weaker because we have less available motor neurons
35. Do all nerve cells have the same threshold and space constant? Why or why not?
The threshold and space constant can vary between nerve cells. This can be caused by changes in the number of ions, the diameter of the axon, and also the amount of myelin
36. What is a myelinated axon? How does saltatory conduction velocity assist the
nervous system in terms of energy, space, and speed? It is an insulating material that increases the resistance of the membrane, which increases the space constant and therefore the conduction velocity. Saltatory conduction makes it so action potential can only occur at the nodes of Ranvier. This makes a much stronger electrical force which pushes the ions at a much faster speed so it requires less space. It also requires less energy because it requires less ions to increase the speed
37. What is the physiological basis for Multiple Sclerosis? It damages the myelin which makes it so the nerve fibers fail to conduct. This leads to vision problems, lack of coordination, and muscle weakness
38. Do Schwann cells or Oligodendrocytes assist in regeneration? Discuss?
Schwann cells proved myelination in the PNS while oligodendrocytes provide myelination in the CNS. However, there are Schwann cells that do not assist in myelination and instead provide sustenance and regeneration for the neurons and are crucial for keeping them alive
39. Compare and contrast electrical synapses with the traditional chemical synapse.
-happens in pre & post synaptic terminals
-uses action potential
-uses gap junction proteins
-happens in smooth & cardiac muscle
40. Why do scientists know so much about the NMJ and the ACh-R over that of all other
We know so much about the NMJ because of the giant squid axon that is 1-2 mm allows us to examine it, and we know more about the ACh-R because bungaratoxin was extracted from a cobra and it binds to ACh-R receptors which allowed us to map out the entire system
41. How do microtubules assist in synaptic transmission? They transport neurotransmitters down to the pre-synaptic terminal by the use of kinesin, and back up by the use of dyelin
42. If you had a drug that blocked
-ligand-gated ion channels
If Na+ was blocked the channel would not fire, if K+ was blocked it would take longer to slow down
It would lead to an accumulation of neurotransmitters in the synaptic cleft which leads to synaptic fatigue
The vesicles would not release so there would be no action potential in the post synaptic terminal
It would lead to hyper excitability because AChE would not be broken down into acetate and choline
There would be no neurotransmitter transport down the axon
How would taking this "prescription" affect the excitability of your muscle?
43. What are the properties of neuroglia?
Unlike neurons they do not have axons or dendrites and they cannot form action potentials. They instead have other functions
∙ Surround neurons and hold them in place
∙ Supply nutrients and oxygen to the neurons
∙ Insulate the neurons from one another
∙ Destroy pathogens and remove dead neurons
44. What are the four classes of neuroglia?
3. Ependymal cells
Which class is important during a stroke (and why?), Astrocytes because they form neural scar tissue, and they help dampen excitotoxicity
Which class is protective again brain damage?
Ependymal cells, they create cerebral spinal fluid
Which assists to increase the conduction velocity of nerve impulses? Oligodendrocytes
Which assists in immune responses?
45. Know the structure/functions of the major brain regions
and which common diseases are associated with which brain regions.
-houses language centers
-most evolved center of brain
-relay station of brain
-thermostat and endocrine center of brain
Cerebellum & Hippocampus:
-learning & memory
-reception/integration with spinal cord
46. What are some common clinical causes of brain damage? -being shaken/jarred
-cerebral vascular accident (stroke)
47. What are the physiological mechanisms underlying a cerebrovascular accident and what are some new
treatments to prevent further neuronal cell death? As the cells die they release a lot of intracellular fluid into the brain. This causes the brain to have an excess number of neurotransmitters and K+. This causes hyper excitability which causes a lot of damage. If you get the individual into the hospital within 3 hours of the stroke, then most of the damage can be reversed without causing too many detrimental results
48. What are some modern technical devices used to detect brain tumors and what are
their principles of operation?
CAT: computerized axial tomography, it uses x-ray absorption MRI: magnetic resonance imaging, it uses the vibration of protons PET: positron emission tomography, it works by oxygen omitting a positron and then giving off gamma ray energy
49. What is plasticity and how is it related to
use-dependent competition for cortical space?
Plasticity is how easily the brain can be shaped or molded. As you get older the brain becomes less and less plastic. Certain areas of the brain become designated for specific tasks and once that happens there is no going back. However, when you are young there is a lot of open cortical space so it is much easier for someone to recover properly from brain damage
50. What are some selective language disturbances that occur due to stroke or genetic defects?
If the Broca’s area is damaged then a person who has had a stroke will understand both written and spoken words, but will have a poor word selection. If there Wernicke’s area was damaged, then they will have perfect articulation but it will all be nonsense. If their facial area motor cortex is damaged, then they will have a speech impediment
51. How does the homunculus cartoon graphically
represent our perceived input and responsive motor output? How does it demonstrate the somatotopic map?
1. It is a distorted graphic representation that is indicative to the relative proportion of input/output
2. It is a somatotopic map because the position of the body parts is important to code information
3. Body is represented “upside down”
52. What cell type does Parkinson's disease target? Be familiar with clinical symptoms, cellular causes and mechanisms, putative causes of this disease, and
present as well as controversial treatments of the disease. How is this disease related to Schizophrenia?
It affects nerve cells in the basal nuclei. It destroys cells that transmit the neurotransmitter dopamine. It causes tremors, rigidity, and postural instability. You can take drugs which block glutamate so dopamine increases but these have side effects of their own. There is also a surgery where you get a pacemaker like device that helps send electrical signals in your brain. Schizophrenia also has to do with dopamine except it is the opposite. Schizophrenia happens when your brain is overstimulated and has too much dopamine
53. What cell type does Alzheimer's disease target? Be familiar with clinical symptoms, cellular causes and mechanisms. How is this disease associated with a metal? It attacks cells that transmit the neurotransmitter ACh in the hippocampus. It causes forgetfulness, confusion, memory loss, and dementia. There is a theory that certain metals (particularly copper) omit amyloid fibers which give off free radicals that damage neurons