Quiz 1 Flashcards
1
Q
5 functions of Plasma Membrane
A
- Signaling 2.Transport 3.Growth 4.Motility 5. divide cells into compartments
2
Q
How thick is the plasma membrane
A
8 to 9 nm
3
Q
What is the most abundant phospholipid?
A
Phosphatidylcholine
4
Q
5 most common phospholipids
A
1.sphingomyelin 2.phosphatidylserine 3.phosphatidylinositol 4.phasphatidyl-ethanolamine 5.glycolipids
5
Q
Structure of glycerol
A
6
Q
phospholipid structure
A
7
Q
True or false phospholipids are distributed symmetrically
A
false
8
Q
What class of enzymes maintains asymmetry of plasma membrane
A
Filpases
9
Q
Glycolipids are made in which organelle
A
Golgi
10
Q
Inside of golgi looks like which surface of cell membrane
A
outer
11
Q
Phospholipids in membrane are usually turned over how frequently?
A
matter of hours
12
Q
5 functions of transmembrane proteins
A
- transporters
- Receptors
- Anchors
- Enzymes
- Structural
13
Q
3 ways porteins/channels can gin access to inside of the cell
A
- Diffusion
- carrier proteins
- Channel Proteins
14
Q
What is spectrin?
A
A protein that is important in forming the RBC’s unusual shape.
15
Q
Proteins with longer carbohydrate chains are called _____
Proteins with shorter chains are called _____
A
proteoglycans
glycoproteins
16
Q
What is lectin
A
Molecule that recognizes and binds to carbohydrates attached to the memebrane of some WBCs
17
Q
Which phospholipid commonly interacts with proteisn to form lipid rafts?
A
spingolipids
18
Q
What is GPI and why is it important?
A
Glycosylphosphatidylinositol (GPI) important for stability
19
Q
3 Ways material can enter the cell
A
- diffusion
- Integral Membrane Protein
- Endocytosis
20
Q
2 types of endocytosis
A
- Pinocytosis
- Phagocytosis
21
Q
What is size of particles ingested with pinocytosis
A
<150nm
22
Q
2 types of Pinocytosis
A
- Clathrin independent
- Receptor mediated Endocytosis
23
Q
True or false clathrin-independent pinocytosis is a constitutive process
A
true
24
Q
What is the main protein we discussed that is involved in clathrin-independent pinocytosis
A
Caveolin
25
What is the protein that cuts off a pinocytotic vessel from the plasma membrane
dynamin
26
What source of energy does dynamin use to cut off vesicle from plasma membrane?
GTP
27
What is the main protein associated with receptor mediated endocytosis?
Clathrin
28
What is adaptin/aP-2
binds clathirin to receptor
29
What word is used to desribe the shape of Clathrin
triskelion
30
What is Rab-5
labels vesicle for transit through the endosomal pathway
31
Is dynamin used with clathrin coated vesicles as well?
yes
32
4 types of ligands that eter the cell via receptor-mediated endocytosis
1. Hormones
2. Growth factors
3. Lymphokines
4. Nutrients
33
What distinguishes early endosomes?
lack of acid hydrolases
34
T/F all endosomes have a H+ ion pumps
T
35
1. pH of early endosome
2. pH of late endosome
3. pH of lysosome
1. ~6
2. 5.5-6
3. ~5
36
What are ESCRT proteins?
Endosomal sorting complex required for transport...label proteins for passage through endocytotic pathway
37
Where are endosomes synthesized?
Where are endosomes packaged and coated?
- ER
- Golgi
38
What two things determine [H+]
1. number of H+ pumps
2. Volume of vescile they have to cover
39
What does mannose-6-phosphate do
tags hydrolases to transport to endosomes and lysosomes
40
Why do lysosomes need highly glycosylated coating?
To protect their membranes from destruction
41
What are rubbery bumps of fatty deposits called?
xanthomas
42
Is Familial Hypercholesterolemia dominant or recessive?
Dominant
43
What is affected/ wrong in patients with Familial Hypercholesterolemia?
There is an absense or malfuction of LDL receptors, so recpetor can't bind to AP-2, so LDL is not endocytosed.
44
Which ethnic group has particularly high prevanelce of Familial Hypercholesterolemia
French Canadian
45
True of false, Phagocytosis is always triggered by activated receptors
true
46
What size particles are ingested via phagocytosis
\>250
47
Which two cell tpes are "professional phagocytes"
1. Macrophage
2. Neutrophils
48
In phagocytosis, how does formation of psedopodia occur?
reorganization of actin cytoskeleton
49
What is it called when a bacterium/particle is coated by antibody or complement?
opsonization
50
What is complement?
protein constituent of blood that is involved in immune reactions
51
Which organelle's membrane is used for autophagy?
ER
52
How is it possible to distinguish between a phagosome and an autophagosome
autophagosome has two laters of membrane since the membrane comes from the ER
53
What are vesicles called that have byproducts in lysosomes that can't be recycled and that aren't excreted ?
lipofuscin
54
2 othe rnames for lipofuscin
1. wear and tear pigment
2. residual bodies
55
Organelles satisfy which two needs for eukaryotic development
1. Increased membrane surface area
2. Specialization to attain complexity
56
4 Benefits of organelles
1. Surface area for membrane dependent functions
2. Compartmentalization
3. Directed flow of proteins
4. Degradation
57
Two categories of organelles
1. Membranous
2. Macromolecular complexes
58
What occurs in ER
protein and lipid synthesis and important storage depot for Ca2+
59
What happens in Golgi?
Proteins from ER are modified and sorted to their specific final locations
60
In cell fractionation of hepatocyte, what percentage of volume is in cytosol.
What percentage is in membrane bound organelles.
Which organelle took up the most %
What was percentage of nucleus
50
50
Mito
6
61
In hepatocyte membrane study...What percentage of the membrane did hte plasma membrane account for? What about ER and mito?
2
50
40
62
What is size range of mitochondria
.5-1 micrometer diameter
63
T/F mito involved in procceses besides aerobic respiration
T
ex urea cycle
64
Mitochondira are associated with which cytoskeleton element
microtubues
65
Mito has how many membranes
how many compartments
2
2
66
In inner membrane of mito the ratio of protein to lipids is
3:1
67
Production of ATP occurs where in mito?
matrix side of inner membrane
68
The business end of the mito is where?
inner membrane
69
How much more energy from oxidation of pyruvate then from glycolyis
15x
70
How many protons need to be pumped to make 1 atp
3
71
72
How much ATP per second from each ATP synthase?
100 ATP
73
What are two things that are increased in regards to mitochondra and increased energy demand
1. number of mitochondria
2. Increased cristae
74
What makes mitochodrial replication complex?
having two-mebranes and two compartments
75
What is different about mtDNA
no histones
76
Most known mtDNA mutations affect hwat?
electron transport/ ATP synthesis
77
MERRF
Myocolonic Epilepsy with Ragged Red Ribers
affects a gene that does what?
encodes tRNA -lysine
78
majority of RNA is what kind of RNA?
rRNA
79
Ribosomes translate which kind of RNA to protein?
mRNA
80
81
During translation mRNA moves in what order through the different sites in the ribosome?
A, P, E
82
\_\_\_\_ subunit of ribosomes some as frame where tRNA anticodon reads mRNA codo, ____ subunit catalyzes peptide bond formation
small
large
83
DNA is translated in which direction
5-3
84
during replication, which subunit of hte ribosome moves first
large
85
Ribosome has how many binding sites and what are they named
4
1. for mRNA
2. A site (aminoacyl)
3. P-Site Peptidyl
4. E-Site Exit
86
Any peptide that will be in a membrane-enclosed structure msut enter the
ER
87
What guides protein to ER
SRP signal recognition particle
88
Any peoptide that will be inserted into the membrane with in the cell will enter the
ER
89
Erythomycin blocks which channel
exit
90
tetracyclines block which site
A site
91
Chloramphenicol blocks what?
Peptidyl transferase rxn
92
are proteasomes abundant?
yes
93
Where are proteosomes located --2 places
cytosol and nucleus
94
how do proteasomes recognize which proteins have to be degraded?
ubiquination
95
4 functions of sER
1. synthesis of membrane lipids
2. synthesis of steroid hormones
3. Durg detox
4. sequestration of calcium
96
Cis face of Golgi is closest to what
ER
97
What kind of modifications are done in Golgi?
glyco modifications of proteins
98
enzymes for protiens are produced where?
ER and then sent to Golgi for packaging
99
what is a secondary lysosome/ heterolysosome?
lysosome in which ingested material is degraded
100
Which enzyme is deficinet in Tay-Sachs
hexosaminidase
101
What accumulates and wherein Tay-Sachs
Glycolipids in lysosomes of neurons
102
Is Tay-Sachs
autosomal recessive/dominant
recessive
103
What happens in Hurler Syndrome
One of the enzymes that breaks down GAGs is affected
104
Besides tay sachs and hurlers, what other type lysosomal disorder?
around 10 glycogen storage disease
105
Besides endocytosis what else uses clathrin
vesicle formation from golgi
106
secretory vesicles have what fold concentration
200-400
107
size of peroxisome?
0.5 micrometer
108
Where are peroxisomes most abundant
liver
kidneys
109
Function of peroxisome--3
1. Beta ox of fatty acids
2. detox of alcohol and drugs
3. synthesis in plasmalogens which make myelin sheaths
110
2 main rxns of Peroxisome?
1. Oxidation
2. Peroxidation
111
IN peroxisomes what two things can happen to hydrogen peroxide
1. reduced to Water
2. Reduces fatty acid
112
What happens in Zellweger Syndrome? Most likely what kind of issue
- Absense of peroxisomal enzymes
- probably packaging issues...enzymes are made, but aren't packaged correctly
113
What happens in Adrenoleukodystrophy
failure of B-ox of fatty acids
Lipids accululate in nervous system and adrenal glands
114
Surface area generates what 3 things.
1. Complexity
2. Differentation
3. Longevity
115
which type of heterochromatin will probably never be unwound? and where is it located
What type of heterchromatin will sometimes be transcribed and where does it go
Constitutive
Stays close to nuclear lamina around the perimeter of the nuclear envelope.
Facultative
More towards the center of the nucleus
116
how big is the perinuclear space
20-50 nm
117
How many pairs of chromosomes do humans have
23
118
How many base paris are wound around 1 pair of histones?
~150
119
solenoid is how many nm
30
120
nucleosome is how many nm
11
121
DNA/ Nucleosome / Solenoid interaction with which portein forms 300 and 700 nm loops
condensins
122
Which protein complex is capable of moving histones in the nucleosome and also of decondensing solenoids to increase avaiilability of a starand of DNA for transcription?
-Does this require energy?
- Nucleosome remodeling complex
- yes
123
What are steps for getting something into the nucleus
4 steps
1) Proteins need NLS
2) Proteins with NLS bind to importin
3) Importins bind to nucleoporins
4) GTP is hydrolyzed and protein is released
124
Which side of nucleus has high [GTP]
nuclear side
125
Where is tRNA synthesized
The nucleolus
126
Where does DNA for rRNA come fro?
DNA from 5 pairs of chromosomes
127
Average size of eukaryotic cell
Aversize of nucleus
10-50micrometers
5--10 micrometers
128
Is rDNA being transcribed in Fibrillar Center
Is rDNA being transcribed in dense Fibrillar Zone
What's happening in Granular Zone
no
yes
ribosomal packaging and processing
129
What are the two subunits of Ribosomes
60s and 70 s
130
What 3 phases are included in interphase
G1, s, G2
131
How long is prophase `
+/- an hour
132
How long is Metaphase
\<1 hour
133
How long is anaphase
\<1/2 hour
134
how long is telophase
minutes
135
How long is S phase
8 hours
136
how long is g1
25
137
about how long is total cell cycle
38 hours
138
What is division of hte nucleus called
karyokinesis
139
\_\_\_ ____ in centrosome are the nucleation sites for MTs
y-tubulin rings
140
When does nucleolus disappear
prophase
141
how does nuclear envoelop break down?
lamin phosphorylated by M-CDK
142
What is the protein called that binds sister chromatids together?
cohesin
143
around how many proteins make up the kinetochore?
over 60
144
astral kinetochores are pulled by which motor protein
dynein
145
polar MTs are pushed by which motor protein
kinesins
146
What are the steps in the break down of cohesin
1. Anaphase Promoting complex (APC) is phosphorylated
2. Securin is ubiquinated and destroyed
3. proteolytic enzyme (separase) is no longer inhibited by securin and it goes and breaks cohesin
147
What phosphorylates the APC
CDK
148
What happens in Anaphase A
Chromes are pulled poleward
149
What happens in Anaphase B?
Poles are pushed apart
150
S-Cdk promotes which phase and is present when?
M-Cdk promotes which phase and is present when?
S phase
Middle of G1, to Middle of M
Mitosis
Beginning of G2 to middle of M
151
How many checkpoints are there
Where are they
What do they check
3.
1) G1 Checkpoint Before S phase
Checks to see if environment is favorable and if there is any DNA damage
2) G2 Checkpoint Before Mitosis
Checks to see if all of the DNA is replicated and if damaged DNA has been repaired
3) Mitosis Checkpoint
Checks to see if all chromosomes are properly attached to spindle
152
How does Rb protein work?
when active it inactivates transcription regulators, An activated G1/S Cdk phosphorylates it and Rb becomes inactive and the transcription regulator becomes active
153
What are the two types of kinsases that activate p53
1) activated during cell stress
2) activated when there's DNA damage.
154
How does p53 work
p53 is phosphorylated by cdk
active p53 causes production of a protein that inhibits the cyclin/Cdk complex that promotes the S phase
If dna doesn't get repaired p53 activates mechanisms for apoptosis
155
Is there an inflammatory response with apoptosis
no
156
What is one of the most powerful activators of cell suicide
release of cytochrome C from damaged mitochodria
157
What does Bc1 2 do?
blocks apoptosis
158
was does caspase do?
trigger cell death
159
4 types of tissues
epithelium, connective tissue, muscle, nerve
160
5 functions of connective tissue
1. Protection
2. absorption
3. secretion
4. sensory perception
5. contractility
161
What kind of stains do you have to use to see basal bodies
eosinophilic
162
What is PKD
polycystic kidney disease
inherited defects in the assembly of cilia
163
What is Bardet-Biedl?
Genes that produce proteins necessary for intraflagellar transport and the formation of cilia
164
Which type of cellular connector (zona occluda, adherens, and desmosome) has cadherins
zona adheres/ adherent junction and desmosomes
165
Waht kind of stain do you have to use to see Basement Membrane/ Basal Surface
PAS
166
what kind of epithelial cells are in respiratory airways
pseudostratifed columnar
167
GI tract is usually what kind of epithelia
simple columnar
168
- In cigarette smokers what happes to epithelium
- acid reflux
- pseudostratified to stratified squamous
- stratified squamous to columnar
169
Type 1 Collagen is found where?
Dermis, tendons, ECM, ligaments,bone
170
Type 2 Collagen fibers are found where?
Cartilage--fibro, hyaline, and elastic
171
Type 3 Collagen fibers are found where?
Reticular Fibers--organ stroma
172
Type 4 Collagen fibers are found where?
basement membranes
173
What is different about type 4 collagen
no fibers
174
Steps in collagen synthesis
1. pro alpha chain is produced
2. post translational modification select lysines and prolines are hydroxylated/ hydrolysines are glycosylated
4. 3 pro alpha chains self assemble
5. secreted outside of cell
6. propeptides cleaved--tropocollagen
7. Assemble into fibrils
175
Which co-factor is needed for collagen to synthesize correctly?
vitamin c
176
What kind of staining is needed to see type 3 collagen
silver
177
What two type of fibers make up elastic fibers
Elastin and Fibrillin
178
Marfan's syndrome is a deficiency in
Fibrillin
179
What are two common examples of structural glycoproteins
Laminin
Fibronectin
180
T/F Fibrillin and Elastin don't require special staining
false
181
GAGs are made up of ___ \_\_\_\_ which are then covalently bonded to ___ \_\_\_ with the exception of ________ (specific GAG)
disaccharide chains
core protein/proteoglycan
hyaluronic acid (hyaluronan)
182
Mucous CT is only present during
the embryonic and fetal periods and i the umbilical cord
183
Macrophage in the liver are called
Kupffer cells
184
Macrophages in the skin are called
Langerhans
185
Macrophages in the bones are called
osteoclasts
186
macrophages differentiate from
monocytes
187
Mast cells bind what type of antibody
IgE
188
2 divisions of connective tissues
1. Cells and 2. ECM
189
