Week Three Day 1 Flashcards
(84 cards)
1
Q
What are the four basic tissue types?
A
311 Reading: epithelial, connective, muscular, and nervous tissues
2
Q
How is connective tissue characterized?
A
311 Reading: Connective tissue is characterized by cells producing very abundant ECM.
3
Q
How is muscular tissue characterized?
A
311 Reading: Muscle tissue is composed of elongated cells specialized for contraction and movement.
4
Q
How is nervous tissue characterized?
A
311 Reading: Nervous tissue is composed of cells with long, fine processes specialized to receive, generate, and transmit nerve impulses.
5
Q
What is parenchyma?
A
311 Reading: The organ’s cells which are responsible for the specialized function of the organ.
6
Q
What is stroma?
A
311 Reading: The cells of which have a supporting role in the organ.
7
Q
How is epithelium characterized?
A
311 Reading: Epithelial tissues are composed of closely aggregated polyhedral cells adhering strongly to one another and to a thin layer of ECM, forming cellular sheets that line the cavities of organs and cover the body surface.
8
Q
Boundary epithelium covers and lines the surfaces of the body, where is it not found?
A
311 PPT (5): Joint cavities
9
Q
Which of the following is not a function of epithelium?
a. Lubrication
b. Absorption
c. Facilitate Diffusion
d. Sensation
e. Protection
f. Support
g. Secretion
h. Excretion
A
311 PPT (5): f.
10
Q
True or False, all epithelia sit on a basement membrane separating them from connective tissue?
A
311 PPT (7): True
11
Q
True or False, all epithelia use active transport to remove waste and receive nutrients?
A
311 PPT (7): False
12
Q
What are Tight junctions (zonula occludens) made of and what is their function?
A
311 PPT (9): Actin micro-filaments (occludins, claudins, tricellulin) that prevent exchange of protein and lipids between the apical and basolateral plasma membranes.
13
Q
What are Adherens junctions (zonula adherens, or belt desmosomes) made of and what is their function?
A
311 PPT (9): Actin micro-filaments and micro-tubules (cadherins, catenin complexes) that link cytoskeltons of adjacent cells to form a cohesive epithelium.
14
Q
What are Desmosomes (macula adherens or spot desmosomes) made of and what is their function?
A
311 PPT (9): Intermediate filaments: keratin 1 and 2 (cadherins) that act as “spot welds” linking cytoskeletal elements of adjacent cells.
15
Q
What are Gap junctions made of and what is their function?
A
311 PPT (9): Connexins (a complex of connexins = a connexon) that allow inter-cellular signaling; and passage of ions and small molecules between cells.
16
Q
What are Hemidesmosomes made of and what is their function?
A
311 PPT (9): Intermediate filaments (integrins and laminins) that bind cells to underlying basement membrane.
17
Q
What is the difference between cilia and microvili in terms of structure?
A
311 PPT (17): Microvilli and stereocilia are made of microfilaments of actin, whereas cilia are made of microtubules.
18
Q
What is the difference between cilia and microvili in terms of function?
A
311 PPT (17): Microvilli and stereocilia increase surface area for absorption, whereas cilia provide movement on the surface of cells and transport proteins within cells.
19
Q
What is stratified epithelium, and which cells are used for its naming?
A
311 PPT (10): Epithelium made of more than one layer of cells and their apical surface.
20
Q
What is simple epithelium?
A
311 PPT (10): Epithelium made of one layer of cells.
21
Q
Squamous epithelium is made from which types of cells?
A
311 PPT (10): Epithelium made of flat cells.
22
Q
Cuboidal epithelium is made from which types of cells?
A
311 PPT (10): Epithelium made of cells that are similar in width and height.
23
Q
Columnar epithelium is made from which types of cells?
A
311 PPT (10): Epithelium made of cells that are taller than they are wide
24
Q
Psuedostratified epithelium is made from which types of cells?
A
311 PPT (10): Epithelium made of cells that look stratified but are in fact all connected to the basement membrane.
25
Transitional epithelium is made from which types of cells?
311 PPT (10): Epithelium made of cells that have large "pillow" or umbrella cells on the apical surface that are capable of stretching.
26
How do you identify keratinized (CORNIFIED) epithelium, and what does this provide?
311 PPT (11): Epithelium that lacks nuclei on the apical surface, protection from dehydration.
27
Where would you find simple squamous epithelium, and what is its function?
311 PPT (12 and 15): Lungs (alveoli), organ lining (mesothelium), blood vessels (endothelium). Diffusion of gases; lubrication; laminar flow of blood, regulates coagulation and vascular tone, allows penetration of white cells.
28
Where would you find simple cuboidal epithelium, and what is its function?
311 PPT (13): Kidney, secretion and absorption.
29
Where would you find simple columnar epithelium, and what is its function?
311 PPT (14): Small intestine, absorption
30
Where would you find stratified squamous epithelium, and what is its function?
```
311 PPT (11): Non-keratinizied in esophagus, vagina, lining of mouth, anal canal; provides protection
Keratinized on epidermis of skin; provides protection and prevents dehydration
```
31
Where would you find stratified cuboidal epithelium, and what is its function?
Found on google: Glands (sweats, salivary, and mammary); provides protection
32
Where would you find pseudo-stratified columnar epithelium, and what is its function?
311 PPT (12): Trachea and upper respiratory tract; usually ciliated to move secreted mucus.
33
Where would you find transitional epithelium, and what is its function?
311 PPT (13): Urinary bladder, ureter, renal calyces, proximal urethra; layers provide protection and surface cells allow distension.
34
Glands are classified into simple and compound, by what?
311 PPT (19): If the glands have branches: compound, if not: simple.
35
How are glands classified by secretory cell arrangement?
311 PPT (19): Tubular (tubes) and acinar/alveoli (hollow balls).
36
Where are compound tubuloacinar glands located?
311 PPT (20): Mammary glands
37
Where are simple branched acinar glands located?
311 PPT (20): Sebaceous gland
38
Where are simple tubular glands located?
311 PPT (20): Small intestine
39
How do merocrine glands secrete their contents?
311 PPT (21): Secretory granules with no loss of cytoplasm.
40
How do apocrine glands secrete their contents?
311 PPT (21): Apical product filled area of cell.
41
How do holocrine glands secrete their contents?
311 PPT (21): Whole cell shed.
42
Under a microscope, a micropipette is used to inject a small amount of fluorescent dye into a single cell of the epithelium. Shortly thereafter, the dye is observed in the immediately adjacent epithelial cells, but not outside the epithelium. The most likely explanation for this apparent dye migration is:
a. The dye was transported in pinocytotic vesicles secreted from the injected cell and taken up by adjacent cells.
b. The dye simply diffused across the cell membrane of the injected cell and passed into adjacent cells.
c. The dye leaked across the zonula occludens junction of the injected cell into adjacent cells.
d. The dye passed through the gap junctions of the injected cell into adjacent cells.
e. The dye was actively transported via membrane pumps from the injected cell into adjacent cells.
```
311 PPT (30):
The correct answer is D, “The low molecular weight dye passed through the gap junctions of adjoining cells.” Although answer A might be theoretically possible, it seems highly unlikely to account for the observation. The fact that the dye remains within the epithelium precludes answer B, which if true, would result in dye spreading outside the epithelium into the surrounding tissue (this might also be expected if answer A were true). Answer C is wrong because the zonula occludens junction represents a tight seal between adjoining epithelial cell membranes, not a conduit connecting the cell interiors. Answer E is wrong because it is inconsistent with known transcellular transport pathways.
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43
The most common kinds of cancer are of epithelial origin and are termed carcinomas. Those derived from glandular epithelial tissue are specifically termed adenocarcinomas. Often, the histological features of a tumor are sufficiently altered to prevent a definitive diagnosis of the tissue of origin.
You are presented with a tumor biopsy that you suspect may be of epithelial origin. Standard H&E staining is suggestive of glandular tissue but not conclusive. You have decided to do immunoperoxidase staining to settle the matter. The presence of which substance would confirm your suspicion of adenocarcinoma?
a. Keratin intermediate filaments
b. Glial fibrillary acidic protein
c. Vimentin intermediate filaments
d. Leukocyte common antigen
e. Desmin intermediate filaments
```
311 PPT (31):
The correct answer is A, “Keratin intermediate filaments.” Keratin intermediate filaments are found in all epithelial cells. The other protein markers are for (B) neuroglial cells, mostly astrocytes; (C) cells of mesenchymal origin, including sarcomas; (D) all white blood cells, especially lymphocytes; (E) muscle cells. Students can find the supporting information in most standard histology textbooks (e.g., Table 2.3 of Ross and Pawlina, 6th ed.) and often in unabridged medical dictionaries, like Dorland’s. This question also provides the opportunity to ask students to explain immunoperoxidase staining.
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44
In certain autoimmune diseases, antibodies are directed against components of the hemidesmosome, which results in the breakdown of proteins linking the attachment plaque to the extracellular matrix. The most likely consequence of this event would be:
a. The junctional complex is weakened, causing gaps to develop between epithelial cells.
b. The intermediate filaments lose their connections to attachment plaques, thereby altering the cytoskeleton of epithelial cells.
c. Perforations develop in the basal membrane of epithelial cells, causing them to swell and rupture.
d. The basement membrane becomes more permeable to water, causing the underlying connective tissue to dehydrate and shrink.
e. The epithelium remains intact but separates from the underlying connective tissue.
```
311 PPT (32):
The correct answer is E, “The epithelium remains intact but separates from the underlying connective tissue.” The autoimmune disease described is bullous pemphigoid. Answer A is wrong because the junctional complex is located on the lateral aspects of adjoined epithelial cells, not the basal aspect where the hemidesmosome is located. Answer B is wrong because the connections of the intermediate filaments to the attachment plaques are located inside the cell, which are unlikely to be affected by the breakdown of anchoring filaments linking the attachment plaques to the basement membrane outside the cell. Answer C is wrong because there is no reason to assume that cleavage of the anchoring filaments would damage the cell membrane. Answer D is wrong because the basement membrane is normally porous to the passage of water, so no increase in permeability is possible.
```
45
What are the three types of neurons involved in a reflex arc?
Review PPT (3) (not sure where in sections):
Sensory: Carries signal from senses to the spinal column where it synapses with a...
Interneuron: Short neuron that carries a signal from the sensory neuron to the...
Motor: Neuron that carries the signal back out to the periphery, near the origin of the signal contracting muscles.
46
Figure 1 in google sheets.
| What are the labeled parts of the neuron?
```
Review PPT (3):
A: Soma or the nucleus; Nucleolus in center
B: Cell Body
C: Axon
D: Axon Hillock
E: Dendrites
F: Nissl bodies or RER
G: Axon Terminals
```
47
Which cells produce myelin in the PNS? In the CNS? And what is their major difference?
312 PPT (31 and 16): Schwann cells in PNS oligodenrocytes in CNS. Schwann cells only wrap on one axon, whereas in CNS oligodendracytes wrap many.
48
What are the supporting cells in the PNS called? Where are they located?
312 PPT (30): Satellite cells, in ganglia
49
What is a nerve?
312 PPT (33): Bundle of axons in the PNS
50
What is a fascicle in regards to neurons?
312 PPT (33): Bundles of axons and Schwann cells in a nerve.
51
What is endoneurium?
312 PPT (33): Surrounding of individual Schwann cells and their enclosed axon.
52
What is perineurium?
312 PPT (33): Surrounding of fascicles.
53
What is epineurium?
312 PPT (33): Surrounding of groups of fascicles and is the outer connective tissue of nerves.
54
What is the role of myelin sheaths?
312 PPT (16): To increase the conduction velocity of axons. (insulation)
55
True or False: CNS neurons are capable of regeneration?
312 PPT (34): False, only PNS neurons can.
56
What is a ganglion?
312 PPT (27): A cluster of cell bodies in the PNS.
57
What is gray matter?
312 PPT (10): Location of nerve cell bodies.
58
How does white matter differ from gray?
312 PPT (10): Mostly axons of cells from the gray matter.
59
How are astrocytes identified and what do they do?
312 PPT (15): Astrocytes contain a intermediate filament GFAP that is unique to them; and they transport materials between neurons and blood, give structural rigidity, store energy, and secrete growth factors.
60
What are microglia?
312 PPT (20): Cells that migrate and phagocyze other cell types in the brain.
61
What is the choroid plexus made of and what are these cells function?
312 PPT (18): Ependymal cells that extend into the ventricles and they secrete CSF.
62
How is the brain protected from most systemically administered antibiotics?
312 PPT (21): The blood brain barrier.
63
True or False: Cations are negatively charged?
313 PPT (5): False
64
What are the two competing forces on an ion?
313 PPT(5): Diffusion via moving to a lower concentration and electric fields via different charges (opposites attract).
65
If Na+ and K+ ions are moving across a membrane at the same rate, would a current be produced? How is the magnitude of currents measured?
313 PPT (5): No, you need a net movement of charge to produce a current. Current is measured in amperes (A).
Remember current direction is defined by the movement of positive ions.
66
How is electrical potential formed? And how is the magnitude of voltage measured?
313 PPT (5): Separation of charges forms electrical potential and they are measured in volts (V).
67
How are membrane potentials made?
313 PPT (10): Selective flow of ions across a membrane via channels. These ions flow with their concentration gradient to form a separation of charge across the membrane.
68
If a cell was permeable to only Na+ ions, where would the equilibrium potential lie?
313 PPT (18): +65 mV
69
If a cell was permeable to only K+ ions, where would the equilibrium potential lie?
313 PPT (18): -97 mV
70
If a cell was permeable to only Ca2+ ions, where would the equilibrium potential lie?
313 PPT (18): +127 mV
71
If a cell was permeable to only Cl- ions, where would the equilibrium potential lie?
313 PPT (18): -71 mV
72
How is equilibrium potential achieved?
313 PPT (16): The electrical work for moving ions is equal to the chemical work for moving ions.
73
If the potassium concentration on the outside of a resting nerve cell is suddenly doubled (with no measurable change in inside concentration or membrane permeability) the intracellular potential will:
A. become more negative
B. remain the same
C. become less negative but not go to zero
D. go to zero
E. go positive
313 Pre-Reading Question 2:
A. Incorrect. Are you certain you didn’t mix up the sign of the potential? ‘Becomes more negative’ is equivalent to ‘hyperpolarize’. If sign was not the problem, consider the fact that resting nerve and muscle cell membranes are much more permeable to K+ than to Na+.
B. No. Since the membrane is permeable to K+ there would be a net movement across the cell membrane. This would change the intracellular potential.
C. Correct. The increased concentration of K+ outside the cell produces a net entry of K+ into the cell since the membrane is highly permeable to potassium, thus transferring positive charge into a cell and depolarizing it (reducing the internal negativity). See comment for more detailed explanation.
D. Incorrect. This would occur only if the external concentration approached that of the internal concentration of potassium. Since external concentration might be about 4 mM and the internal about 150 mM, a doubling of external [K+] will not achieve this result (i.e., it would not equalize the internal and external concentrations).
E. Wrong. The intracellular potential could go more positive than 0 mV only if the extracellular [K+] exceeded that inside the cell. Merely doubling external [K+] would not achieve this result. On the other hand, if the PNa were greatly increased, this kind of result could be achieved.
74
When would you observe a resting potential of 0 mV across a cell membrane?
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313 Notes (I'm sure it is in the preclass reading as well):
If the cell were completely permeable to all ions there would be no membrane potential formed.
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75
Place these events of neuro transmitter release of a muscular junction in the correct order:
A. ACh diffuses across the synaptic cleft to the muscle where it binds to nicotinic ACh receptors. In skeletal muscle these receptors also act as non-selective cation channels. Binding of ACh opens these cation channels, leading to a depolarization of the muscle called the end-plate potential. The end-plate potential is a large depolarization that under normal conditions always leads to an action potential in the muscle.
B. ACh is removed from the synaptic cleft by enzymatic degradation (by acetylcholinesterase) and by diffusion.
C. Exocytosis of vesicles filled with acetylcholine (ACh) occurs.
D. An action potential propagates down
the axon of the motorneuron and depolarizes its synaptic terminal.
E. Voltage-gated Ca2+ channels open and permit Ca2+ to enter the synaptic terminal.
314 Pre-Reading 1-2:
| D; E; C; A; B
76
How are amino acid neurotransmitters cleared from a synapse?
Review PPT (6): Taken back up by presynaptic neuron or glia.
77
How is ACh and Monoamine neurotransmitters cleared from a synapse?
Review PPT (6): Broken down (ACh esterase) or taken back up (dopamine).
78
What would release of glutamate onto an ionotropic recepter cause?
314 Pre-Reading (4): Excitation or depolarizing of post synaptic potential.
79
What would release of GABA onto an ionotropic recepter cause?
314 Pre-Reading (5): Inhibatory or hyperpolarizing of post synaptic potential.
80
What would release of glycine onto an ionotropic recepter cause?
314 Pre-Reading (5): Inhibatory or hyperpolarizing of post synaptic potential.
81
What would release of ACh onto a metabotropic recepter cause?
314 Pre-Reading (4) Either excitation or inhibition of the post synaptic potential, depending on the location of the receptor.
82
Why are ionotropic receptors capable of acting quickly on a post-synaptic potential and metabotropic not?
314 Pre-Reading (6-7): Ionotropic receptors also act as ion channels, whereas the metabotropic receptors rely on GPCR cascade.
83
True or False: Spatial integration is the integration of different potentials from repetitive activation of of one synaptic input.
314 Pre-Reading (8): False; this is temporal summation. Spacial is similarly timed potentials from different locations.
84
Which of the following is not true in regards to electrical synapses (gap junctions):
A. They are faster than all chemical synapses.
B. They are not selective.
C. There are few good drugs that act on them.
D. They are rarely located in the brain.
E. The potential at which no net current flows is non-zero.
314 Pre-Reading (11): E; If this were true the gap junction would have to provide some sort of ionic selectivity.
