CELL Flashcards

1
Q

are the basic structural and functional units of all multicellular organisms.

A

Cells

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2
Q

Cells can be divided into TWO MAJOR COMPARTMENTS

A

Cytoplasm
Nucleus

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3
Q

where the organelles are embedded

A

Cytoplasm

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4
Q

stores the DNA and nucleolus

A

Nucleus

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5
Q

TWO BASIC TYPES OF CELL

A

EUKARYOTIC CELL
PROKARYOTIC CELL

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6
Q

with distinct membrane-limited nuclei surrounded by cytoplasm containing various membrane-limited organelles

A

EUKARYOTIC CELL

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7
Q

Unicellular eukaryotic cells

A

Fungi

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8
Q

It has no nuclear membrane, thus, nuclear material mixes with the rest of the cytoplasm

A

PROKARYOTIC CELL

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9
Q

present in prokaryotes that are important in
determining whether bacteria are gram
positive or gram negative

A

polysaccharide peptidoglycan

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10
Q

Difference in cell division between E and P

A

E= Mitosis
P= binary fission

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11
Q

Only human cell with flagella

A

Sperm cell

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12
Q

Main difference of types of cells

SIZE

A

P= 0.2-2.0 um

E= 10-100 um

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13
Q

Main difference of types of cells

NUCLEUS

A

P= no nuclear membrane or nucleoli
E= true nucleus

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14
Q

Main difference of types of cells

MEMBRANE-ENCLOSED ORGANELLE

A

P= Absent
E= Present

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15
Q

Main difference of types of cells

FLAGELLA

A

P= Consists of two protein building blocks
E= Complex, multiple microtubules

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16
Q

Main difference of types of cells

GLYCOCALYX

A

P= Present as a capsule or slime layer

E= present in some cells that lack a cell wall

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17
Q

Main difference of types of cells
CELL WALL

A

P= usually present; complex chemical composition

E= when present is chemically simple

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18
Q

Main difference of types of cells

PLASMA MEMBRANE

A

P= No carbohydrates and generally lack sterols

E= Sterols and carbohydrates as receptors

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19
Q

Main difference of types of cells

CYTOPLASM

A

P= No cytoskeleton or cytoplasmic streaming

E= Cytoskeleton with cytoplasmic streaming

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20
Q

Main difference of types of cells
RIBOSOMES

A

P= Smaller size (70s)

E= Larger size (80s); smaller size (70s) in organelles

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21
Q

Main difference of types of cells

CHROMOSOME (DNA)

A

P= single circular chromosome no histones

E= Multiple linear chromosome with histones

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22
Q

Main difference of types of cells

SEXUAL RECOMBINATION

A

P= none: transfer DNA only

E= meiosis

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23
Q

is located outside the nucleus
It contains organelles and inclusions in an aqueous gel called the cytoplasmic matrix

A

cytoplasm

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24
Q

The cytoplasm is located outside the nucleus
It contains organelles and inclusions in an aqueous gel called the

A

cytoplasmic matrix

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25
Organelles are described as:
1. Membranous 2. Non-membranous
26
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY NUCLEUS
3-10 um Largest organelle, visible nucleoli and chromatin pattern regions Surrounded by two membranes, nuclear pore complexes , perinuclear cisternal space, euchromatin and heterochromatin obeservation
27
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY NUCLEOLUS
1-2 um Roughly circular, basophilic, interphase observation with interference microscopy Dense, nonmembranous structure containing fibrilar and granular material
28
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY PLASMA MEMBRANE
0.008-0.01 Not visible External membrane and membranes surrounding membranous organelles , inner and outer electron dense later with intermediate electron-lucent layer
29
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY rER
5-10 um^2 (area) Basophilic- ergastoplasm Flattened sheets, sacs, and tubes of membranes with attached ribosomes
30
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY sER
Throughout cytoplasm Not visible, cytoplasm in region of sER may exhibit distinct eosinophilia Flattened sheets, sacs, and tubes of membranes without ribosomes
31
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY GOLGI APPARATUS
5-10 um^2 (area) Sometimes observed as negative staining region, appears as networks in heavy metal stained preparations, living cells observation with interference Stack of flattened membrane sheets, often adjacent to one side of nucleus
32
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY SECRETORY VESICLES
0.050-1.0 Only when large (zymogen in granules of pancreas) Many small, membrane-bound, uniform diameter, polarize on one side of cell
33
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY MITOCHONDRIA
0.2-7 favorable situations e.g. liver and nerve cells- miniscule dark dots; living cells stained with janus green two membrane system, cristae; tubular cristae in steroid producing cells
34
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY ENDOSOMES
0.02-0.5 Not visible Tubulovesicular structures
35
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY LYSOSOMES
0.2-0.5 special enzyme histochemical staining membrane bound electron dense vesicles
36
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY PEROXISOMES
0.2-0.5 Special enzyme histochemical staining Membrane bound electron dense with crystalloid inclusions vesicles
37
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY CYTOSKELETAL ELEMENTS
0.006-0.025 observed when organized into large structures e.g. muscle fibrils long linear staining pattern with width and features characteristic of each filament type
38
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY RIBOSOMES
0.0025 not visible minute dark dots, often associated with the rER
39
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY GLYCOGEN
0.010-0.040 purple haze - toluidine blue stained specimens nonmembranous extremely dense grapelike inclusions
40
characteristics appearance of organelles SIZE LIGHT MICROSCOPY ELECTRON MICROSCOPY LIPID DROPLETS
0.2-5 up to 80 readily visible when extremely large e.g adipocytes; large empty holes in section non membranous inclusions generally appear as avoid in the section
41
phospholipids form a bilayer in which the hydrophilic phosphate heads face outwards adhering the water, while the hydrophobic lipid tails aggregate inside what model
Amphipathic
42
is a lipid-bilayered structure visible with transmission electron microscopy.
plasma membrane
43
has hydrophilic heads and hydrophobic tails (fatty acid chain) what model
Fluid mosaic model
44
Plasma membrane composition
Phospholipid Cholesterol Protein molecules
45
CLINICAL SIGNIFICANCE of plasma membrane
dividing and dying cells, and during cell movement, often manifests as morphologic changes in the cell’s plasma membrane
46
Cell injury, in dividing and dying cells, and during cell movement, often manifests as morphologic changes in the cell’s plasma membrane, which results in the formation of plasma-membrane blebs aka
apoptotic bodies
47
is caused by the detachment of the plasma membrane from underlying actin filaments of the cell cytoskeleton.
Blebbing
48
act on actin filaments such as phalloidin and cytochalasin-B cause extensive membrane blebbing
Cytoskeletal poisons
49
are fungal metabolites that are toxic and poisonous to cytoskeleton; when an individual is exposed to these, he/she will suffer from cytoskeletal poisoning; induces apoptosis and eventually causes blebbing of cell
phalloidin and cytochalasin-B
50
elevated portion of plasma membrane; function for signaling which contains receptors - described as “platforms surrounded by ocean of lipids” - contains receptors that may function in cell recognition, metabolism, or hormone receptor binding,
Lipid raft
51
protein integrated in the lipid bilayer
integrated in the lipid bilayer
52
protein the ones attached to the surfaces; contains receptors (carbohydrates)
Peripheral protein
53
Functions of Plasma Membrane:
1. Communication 2. Intercellular connection 3. Physical barrier 4. Selective permeability
54
1. Integral proteins are incorporated directly in the lipid bilayer can be viewed under electron microscope through the process called
Freeze fracture
55
enables us to cut the bilayer in its middle portion revealing now the E-face and P- face
Freeze fracture
56
backed by Extracellular space; External (backed by the external environment of the cell)
E-face
57
backed by cytoplasm/Protoplasm
P-face
58
is more granular as viewed under electron microscope. It is in the_______ that we see a larger amount of integral protein
P-face
59
6 BROAD CATEGORIES OF INTEGRAL MEMBRANE PROTEINS
1. Pumps 2. Channels 3. Receptor 4. Linker 5. Enzymes 6. Structural Proteins
60
serves to transport certain ions (Na+, K+) and metabolic precursors of macromolecules actively across membranes.
Pump
61
allow the passage of small ions, molecules, and water across the plasma membrane in either direction
Channels
62
allow recognition and localized binding of ligands (molecules that bind to the extracellular surface of the plasma membrane)
Receptor
63
anchor the intracellular cytoskeleton to the extracellular matrix links a structure from the inside of a cell with a structure from the outside
Linker
64
catalyzing cellular reactions, and have a variety of roles in cell ATP synthase is the major protein of the inner mitochondrial membrane.
Enzymes
65
Aka “junctions in the cell” or “cell-to-cell junctions” Proteins that links one cell to another cell
Structural Proteins
66
Serve as selective barrier regulating the passage of materials into and out of the cell and facilitating the transport of specific molecules.
PLASMA MEMBRANE
67
Has a role in keeping constant ion content off the cytoplasm
PLASMA MEMBRANE
68
Carry out a number of specific recognition and signaling functions
PLASMA MEMBRANE
69
an uncommon disorder that causes inflammation of the blood vessels in your nose, sinuses, throat, lungs and kidneys, auto immune disorder that attacks collagen causing hemoptysis
Granulomatosis with polyangiitis (previously known as Wegener's granulomatosis)
70
MECHANISMS OF TRANSPORT ACROSS THE PLASMA MEMBRANE
Passive Active Vesicular
71
movement of small molecules that are unassisted; not requiring expenditure of energy
Passive transport
72
3 MAJOR TYPES OF PASSIVE TRANSPORT:
Simple diffusion Facilitated diffusion Osmosis
73
movement of ions and small, polar molecules down their concentration gradient across selectively permeable membrane
Facilitated diffusion
74
Facilitated diffusion movement of ions and small, polar molecules down their concentration gradient across selectively permeable membrane by a
transport protein.
75
is a transport protein that facilitates entry of ions into the membrane (active)
sodium-potassium pump
76
2 Classes of Transport Proteins
Carrier Proteins Channel Proteins
77
 transfer small, water-soluble molecules  they are highly selective, often transporting only one type of molecule  Examples: Na/K pump or H pump (active) and glucose carriers (passive)
Carrier Protein
78
 also transfer small, water-soluble molecules.  usually contain a pore domain that serves as the ion- selectivity filter  transport can be regulated by membrane potentials, neurotransmitters or mechanical stress  good examples are gated channels
Channel Proteins
79
Channel Proteins transport can be regulated by
membrane potentials, neurotransmitters or mechanical stress
80
Channel proteins that are regulated by membrane potentials example
voltage gated ions
81
Channel proteins that are regulated by neurotransmitter example
ligand ions regulated by acetylcholine
82
Channel proteins that are regulated by mechanical stress example
seen in skin and ear that responds to vibration
83
diffusion of water across selectively permeable membrane.
Osmosis
84
movements of substances requiring expenditure of energy
ACTIVE PROCESSES
85
transport of ions or small molecules across the membrane against a concentration gradient by transmembrane protein pumps.
Active transport
86
a process that involves configurational changes in the plasma membrane at localized sites and subsequent formation of vesicles from the membrane (ENDO) or fusion of vesicles with the membrane (EXO)
VESICULAR TRANSPORT
87
2 MAJOR FORMS OF VESICULAR TRANSPORT:
a. ENDOCYTOSIS b. EXOCYTOSIS
88
brings molecules and other substances into the cell It is associated with the formation and budding of vesicles from the plasma membrane.
ENDOCYTOSIS
89
3 Different Mechanisms of Endocytosis
Pinocytosis
90
The nonspecific ingestion of fluid and small protein molecules via small vesicles Aka “cell drinking”
Pinocytosis
91
Is the separation of vesicle from plasma membrane
vesicle scission
92
vesicle scission are facilitated by
Mechanoenzymes
93
Example of mechanoenzyme
GTPase enzyme – dynamin
94
ingestion of large particles such as cell debris, bacteria and other foreign materials aka “cell eating”
Phagocytosis
95
in phagocytosis plasma membrane sends out______________ to engulf phagocytosed particles into large vesicles called phagosomes
pseudopodia
96
Phagocytosis is an __________ dependent endocytosis
Actin
97
Phagocytosis requires depolymerization and repolymerization of the actin filaments for
pseudopodal extension
98
Endocytosis that allows entry of specific molecules into the cell
Receptor-Mediated Endocytosis
99
accumulate in well defined regions of the cell membrane
Cargo receptors
100
In receptor mediated processes, clathrin interacts with the cargo receptor via another coating-protein complex, _________ , which is instrumental in selecting appropriate cargo molecules for transport
adaptin
101
is the movement of an organism or entity in response to a chemical stimulus. Somatic cells, bacteria, and other single-cell or multicellular organisms direct their movements according to certain chemicals in their environment.
Chemotaxis
102
are small soluble molecules that bind to receptors on leukocytes causing their stimulation, polarization, and locomotion, in part through the activation of the integrin adhesion molecules.
Chemoattractants
103
the medical term for when blood vessels in your body widen, allowing more blood to flow through them and lowering your blood pressure
Vasodilation
104
the passage of blood cells through the unruptured wall of a blood vessel into the surrounding tissues.
diapedesis
105
recognize and bind specific molecules such as cargo proteins that come in contact with the plasma membrane.
Cargo receptors
106
are recognized by adaptin that helps select and gather appropriate complexes for transport into cells.
Cargo receptor–molecule complexes
107
Clathrin molecules then bind to the adaptin– cargo receptor–molecule complex to assemble into a shallow basketlike cage and form a
coated pit.
108
Clathrin interactions then assist the plasma membrane to change shape to form the coated pit that becomes pinched off from the plasma membrane dynamin as a
coated vesicle.
109
a GTPase that will pinch off the vesicle from the plasma membrane
Dynamin
110
After budding and internalization of the vesicle, the coat proteins
Removed
111
the process by which a vesicle moves from the cytoplasm to the plasma membrane, where it discharges its contents to the extracellular space synthesize molecules and other molecules leave the cell
EXOCYTOSIS
112
2 General Pathways Concerning Exocytosis
Constitutive Pathway Regulated Secretory Pathway
113
substances designated for export are continuously delivered in transport vesicles to the plasma membrane (similar to pinocytosis)
Constitutive Pathway
114
TEM reveals that cells that do constitutive pathway lack
secretory granules
115
Constitutive pathway is seen in secretion of
immunoglobulins by plasma cells and of procollagen by fibroblasts
116
a regulatory event (hormonal or neural stimulus) must be activated for secretion to occur
Regulated Secretory Pathway
117
Regulated Secretory Pathway seen in specialized cells, such as
endocrine and exocrine cells and neurons
118
Newly synthesized proteins from the rough endoplasmic reticulum are delivered in_________ to the Golgi apparatus.
COP-II– coated vesicles
119
After additional modification in the Golgi apparatus, sorting, and packaging, the final secretory product is transported to the plasma membrane in vesicles that form from the
the trans-Golgi network (TGN).
120
Membrane bound organelles
Endosomes, Lysosomes, endoplasmic reticulum, ribosomes, mitochondria, Golgi apparatus, peroxisomes,
121
just like lysosome, but do not contain hydrolytic enzyme vacuoles that surround the materials that were internalized during endocytosis
ENDOSOMES
122
are membrane enclosed compartments associated with all the endocytic pathways
Early Endosomes
123
Early Endosomes Cellular localization:
found in the more peripheral cytoplasm
124
Early Endosomes Morphology:
have a tubulovesicular structure
125
Early Endosomes State of acidification:
exhibits only a slightly acidic environment (pH 6.2 to 6.5) than the cytoplasm of the cell
126
Early Endosomes Function:
to sort and recycle protein internalized by endocytic pathways
127
the ________ the endosomes in the cell, the _________ they are
DEEPER: MORE ACIDIC
128
are vesicles originating in early endosomes travelling to deeper structures in the cytoplasm Typically mature into lysosomes
Late Endosomes
129
Late Endosomes Cellular localization
central or deeper portion of the cell; positioned near the Golgi apparatus and the nucleus
130
Late Endosomes Morphology:
have a more complex structure and often exhibit onion-like internal membranes
131
Late Endosomes State of acidification:
more acidic, averaging pH 5.5
132
endocytosed proteins are transported via
multivesicular bodies (MVB)
133
TWO DIFFERENT MODELS that explain the origin and formation of the endosomal compartments in the cell:
Stable Compartment Model Maturation Model
134
describes early and late endosomes as stable cellular organelles Early endosomes, late endosomes, and lysosomes are separate organelles
Stable Compartment Model
135
early endosomes are formed then matures to late endosomes and then to lysosomes.
Maturation Model
136
Lysosome biogenesis, two types
CONSTITUTIVE SECRETORY PATHWAY ENDOSOMAL GOLGI-DERIVED COATED VESICLE SECRETORY PATHWAY
137
Shows the maturation model of lysosomal formations A continuous process
CONSTITUTIVE SECRETORY PATHWAY
138
Shows the stable compartment model because lysosomal proteins are both delivered separately in early and late endosomes
ENDOSOMAL GOLGI-DERIVED COATED VESICLE SECRETORY PATHWAY
139
Lysosomes are Membrane-limited vesicles that contain about
40 hydrolytic enzymes.
140
Lysosomal enzymes are synthesized in the rER and sorted in the Golgi apparatus based on their binding ability to
M-6-P receptors.
141
Most common enzymes in lysosomes are
hydrolases: i proteases ii nucleases iii phosphatases iv phospholipases v sulfatases vi β-glucuronidase
142
Lysosomal membrane has unusual phospholipid structure that contains cholesterol and a unique lipid called
lysobisphosphatidic acid
143
Lysosome Membrane proteins:
a. lysosome-associated membrane proteins (lamps) b. lysosomal membrane glycoproteins (lgps) c. lysosomal integral membrane proteins (limps)
144
an agent used in the treatment and prevention of malaria, is a lysosomotropic agent that accumulates in the lysosomes
Chloroquine
145
PATHWAYS OF MATERIAL DELIVERY FOR INTRACELLULAR DIGESTION IN LYSOSOMES
Extracellular large particles Extracellular small particles Intracellular particles
146
Extracellular large particles such as bacteria, cell debris, and other foreign materials are engulfed in the process of
phagocytosis
147
Extracellular small particles such as extracellular proteins, plasma-membrane proteins, and ligand– receptor complexes are internalized by
pinocytosis and receptor-mediated endocytosis
148
Intracellular particles such as entire organelles, cytoplasmic proteins, and other cellular components are isolated from the cytoplasmic matrix by endoplasmic reticulum membranes, transported to lysosomes, and degraded by
autophagy
149
is a process in which the cell uses lysosomes to dispose of excess or nonfunctioning organelles or membranes. Membrane that appears to emerge from the SER encloses the organelles to be destroyed, forming an autophagosome that then fuses with a lysosome for digestion of the contents.
Autophagy
150
3 WELL-CHARACTERIZED PATHWAYS OF AUTOPHAGY:
Macroautophagy Microautophagy Chaperone-mediated autophagy
151
A portion of the cytoplasm or an entire organelle is first surrounded by the isolation membrane of endoplasmic reticulum, to form a vacuole called an autophagosome which matures into lysosomes.
Macroautophagy
152
which fuses with a lysosome for digestion of the enclosed material
Autophagosome
153
Cytoplasmic proteins are degraded in a slow, continuous process under normal physiologic condition. Small cytoplasmic soluble proteins are internalized by invagination of the lysosomal membrane.
Microautophagy
154
This process is activated during nutrient deprivation and responsible for the degradation of approximately 30% of cytoplasmic proteins in organs such as the liver and kidney
Chaperone-mediated autophagy
155
Chaperone-mediated autophagy requires assistance from specific cytosolic chaperones such as
heat-shock chaperone protein called hsc73.
156
active organelles, are generally somewhat larger and have more heterogenous appearance in the TEM because of the wide variety of materials they may be digesting
Heterolysosomes
157
a debris-filled vacuole resulting from hydrolytic breakdown of the contents of lysosomes
Residual body
158
Residual body can accumulate as
lipofuscin
159
is used by cells to destroy abnormal proteins that are misfolded, denatured, or contain abnormal amino acids.
Proteasome-mediated degradation
160
Proteasome-mediated degradation also degrades normal short-lived regulatory proteins that need to be rapidly inactivated and degraded such as
mitotic cyclins that regulate cell cycle progression, transcriptional factors, tumor suppressors, or tumor promoters
161
PROTEASOME COMPLEX aka
26s Proteasome complex
162
26s Proteasome complex has the following components
a. 19s regulatory protein b. 20s core protein c. 19s regulatory protein
163
This degradation pathway involves tagging proteins destined for destruction by a polyubiquitin chain and its subsequent degradation in proteasome complex with the release of free reusable ubiquitin molecules.
Proteasome-mediated degradation.
164
Ubiquitin in the presence of ATP is activated by a complex of three ubiquitin-activating enzymes _________________ to form a single polyubiquitin chain that serves as the degradation signal for the 26S proteasome complex.
E1, E2, and E3
165
Loss of proteasome function because of mutations in the system of ubiquitin activating enzymes that leads to a decrease in protein degradation and their subsequent accumulation in the cell cytoplasm example of diseases
Angelman syndrome and Alzheimer's disease
166
is a genetic disorder. It causes delayed development, problems with speech and balance, intellectual disability, and, sometimes, seizures. People with _________ often smile and laugh frequently, and have happy, excitable personalities
Angelman syndrome
167
Angelman syndrome is a severe neurological disorder characterized by mental retardation, absent speech, ataxia, seizures, and hyperactivity. The gene affected in this disorder is
UBE3A, the gene encoding the E6-associated protein (E6AP) ubiquitin-protein ligase.
168
is thought to be caused by the abnormal build-up of proteins in and around brain cells
Alzheimer's disease
169
One of the proteins involved in Alzheimer's is called_________ , deposits of which form plaques around brain cells. The other protein is called________ , deposits of which form tangles within brain cells.
amyloid tau
170
Accelerated degradation of proteins by overexpressed proteins involved in system examples are infections with
human papilloma virus
171
Discovery of specific proteasome inhibitors holds promise for treatment of
cancers and certain viral infections
172
 convoluted membranous network  Extends from the surface of the nucleus to the cell membrane  Encloses a series of intercommunicating channels and sac, called cisternae
ENDOPLASMIC RETICULUM
173
 prominent in cells specialized for protein synthesis  consists of saclike and parallel stacks of flattened cisternae  has attached polyribosomes  basophilic due to attached ribosomes
Rough Endoplasmic Reticulum
174
The _________ in secretory cells is the light microscopic image of the organelle called the rough endoplasmic reticulum (rER).
ergastoplasm
175
Protein synthesis the two processes
Transcription Translation
176
production of proteins by the cell begins within the nucleus in which the genetic code for a protein is transcribed from DNA to pre mRNA then to mRNA after post transcriptional modifications
Transcription
177
in which the coded message contained in the mRNA is read by ribosomal complexes to form a polypeptide. — Polyribosome complex (polysome) are formed by binding of single cytoplasmic mRNA to many ribosomes
Translation
178
Proteins synthesized in the RER can have several destinations
a. Intercellular storage b. Provisional storage in cytoplasmic vesicles prior to exocytosis c. Integral membrane proteins
179
1- antitrypsin deficiency can lead to?
emphysema (COPD) and impaired liver function.
180
protects the lungs from neutrophil elastase
alpha 1-antitripsin
181
necessary to digest cells or bacteria in the lungs to promote healing
neutrophil elastase
182
Site of protein synthesis which will be transmitted to Golgi complex for packaging and secretion out of the cell
RIBOSOME
183
Inhibits protein synthesis by attacking ribosomes
Antibiotics
184
Ribosomes in cytosol has
four segments of rRNA and approximately 80 different proteins
185
Polyribosomes are intensely basophilic due to
the phosphate groups that act as polyanions.
186
Several types of antibiotics inhibit protein synthesis by binding to different portions of bacterial ribosomes — Examples:
aminoglycosides (streptomycin) macrolides (erythromycin) lincosamides (clindamycin tetracyclines chloramphenicol
187
 lack bound polyribosomes  continuous with RER  cisternae are often more tubular and appear as interconnected channels
Smooth Endoplasmic Reticulum (SER)
188
Macrophages of the liver
Kupffer cells monocyte-derived macrophages (MoMϕs).
189
Macrophages of the lungs
Alveolar macrophages interstitial macrophages (IM) act as gatekeepers of the vasculature and lung interstitium
190
Macrophages of the skin
langerhans
191
Macrophages of the nervous
microglia
192
Macrophages of the kidney
mesangial cells
193
Macrophages of the connective tissues
histiocytes
194
Macrophages of the bones
osteoblasts
195
Macrophages of the spleen
littoral cells
196
1. Glycogen and lipid metabolism 2. Detoxification reactions of potentially harmful exogenous molecules 3. Temporary Ca2+ sequestration 4. Phospholipids and steroids synthesis
Smooth Endoplasmic Reticulum (SER)
197
Can be caused by the failure of sER to convert bilirubin to bile
Jaundice
198
GOLGI APPARATUS is named after
Camilo Golgi
199
generally, it is located near the ER and is the principal "traffic director” for cellular proteins.
GOLGI APPARATUS
200
small membrane-enclosed carriers where material from RER move to the Golgi apparatus
Transport vesicles
201
Transport vesicle merge with golgi-receiving region, which is known as the
cis face
202
Shipping or______ , larger saccules or vacoules carry completed protein products to organelles away from the golgi
trans face
203
Proteins and lipids undergo a series of posttranslational modifications that involve remodeling of _____________ previously added in the rER as they travel through the Golgi stacks.
N-linked oligosaccharides
204
means thread
mitos
205
usually depicted as lozenge-like or sausage-like organelles. It is a membrane-enclosed organelle, each with the general structure of the plasma membrane, and with arrays of enzymes specialized for cellular respiration (burning glucose) and production of cellular energy (ATP)
MITOCHONDRIA
206
Mitochondria possess two membranes that delineate distinct compartments.
1. Inner mitochondrial membrane surrounds a space called the matrix 2. Outer mitochondrial membrane is in close contact with the cytoplasm
207
a series of infoldings in the inner mitochondrial membrane
Cristae
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are spherical organelles enclosed by a single membrane and named for their enzymes producing and degrading hydrogen peroxide, H2O2
PEROXISOMES
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Peroxisomes contain oxidative enzymes
Oxidases Catalase
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removes hydrogen atoms that are transferred to molecular O2 producing H2O2
Oxidases
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Peroxisomes forms in two ways:
 budding of the precursor vesicles from the ER or  Growth and division of preexisting peroxisomes
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breakdowns H2O2, which is potentially damaging to the cell
Catalase
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Found in cells that store product until its release by exocytosis is signaled by metabolic, hormonal, or neural message
SECRETORY GRANULES
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with dense content of digestive enzymes
Zymogens granules
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A structure that confer cell rigidity to help maintain cell shape
MICROTUBULES
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MICROTUBULES, fine tubular structures also organized into large arrays called ________ in the cilia and flagella
axonemes
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MICROTUBULES are polymeric structures composed of equal parts of
alphatubulin and beta- tubulin
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CYTOSKELETON is composed of
MICROTUBULES MICROFILAMENTS INTERMEDIATE FILAMENTS
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Functions of microtubules
 Intracellular vesicular transport  Movement of cilia and flagella  Attachment of chromosome to the mitotic spindle  Cell elongation and movement  Maintenance of cell shape
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 composed of actin  allow cellular motility and most contractile activity in cells
MICROFILAMENTS
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MICROFILAMENTS function
 Anchorage and movement of membrane protein  Formation of the structural core of microvilli  Locomotion of cells  Extension of cell processes (e.g., pseudopodia during phagocytosis)
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 rope-like filaments, intermediate in size between microtubules and microfilament  Diameter: averaging 10 nm
INTERMEDIATE FILAMENTS
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Six major classes of intermediate filaments
1. Keratin 2. Vimentin 3. Neurofilament 4. Lamins 5. Desmin 6. Glial filaments
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INTERMEDIATE FILAMENTS present only in epithelial cells
Keratin
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INTERMEDIATE FILAMENTS found in most cells derived from mesenchyme
Vimentin
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INTERMEDIATE FILAMENTS present in cell body and processes of neurons
Neurofilament
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INTERMEDIATE FILAMENTS form the nuclear lamina inside the nuclear envelope
Lamins
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INTERMEDIATE FILAMENTS found in almost all muscle cells
Desmin
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INTERMEDIATE FILAMENTS Glial Fibrillary Acidic Proeteins (GFAP), present in glial cells
Glial filaments
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have little or no metabolic activity, but contain accumulated metabolites or other substances not enclosed by membrane o Fat droplets o Glycogen granules o Lipofuscin o Hemosiderin
CYTOPLASMIC INCLUSIONS
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CYTOPLASMIC INCLUSIONS include
Centrosome Centrioles Flagella Cilia
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centrosphere or cell center  specialized zone of the cytoplasm containing the centrioles  center of activity associated with cell division  called diplosome in nondividing cells  EM: hollow cylinder closed at one end and open at the other
Centrosome
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self-duplicating organelles that exhibit continuity from one cell generation to another  Double in number immediately before cell division  Prominent in mitosis  Essential for the formation of cilia and flagella  Serve as basal bodies and sites of epithelial cilia
Centrioles
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long, semi-rigid, helical, hollow tubular structures mostly composed of protein, flagellin Show undulating wave (moving smoothly up and down) type of movement
Flagella
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 Hair-like processes  Very numerous in: – Epithelial cells of upper RT – Parts of female and reproductive tracts – Ependymal lining the cavities of the CNS
Cilia