Exam 2 Flashcards
1
Q
What is the cell membrane made of?
A
Phospholipid Bilayer (hydrophilic head and hydrophobic tail) Proteins and Lipids
2
Q
what kind of bonds are in the membrane?
A
CIs double bonds
3
Q
T/F Cholesterol can change properties of the cell membrane
A
T-Stiffens
4
Q
T/F The cell membrane is symmetrical
A
False but when cells die asymmetry is lost
5
Q
What are the types of proteins involved in transport across a membrane?
A
Carrier Protein and Channel Proteins
6
Q
What do carrier proteins transport across a cell membrane?
A
Solutes
7
Q
What do Channel Proteins Carry across a Cell?
A
Ions
8
Q
What are the two types of ion channels?
A
Gated and open
9
Q
T/F Are the open channels always open?
A
T
10
Q
What is another name for an open channel?
A
Leak Channels
11
Q
What can go through an open channel?
A
K+
12
Q
What two ways can a gated channel be opened?
A
Voltage (Na+ or K+) or A Ligand binding (Na+)
13
Q
What binds to a ligand binding gated channel?
A
Na+
14
Q
What is membrane potential?
A
Electrical difference between inside and outside the cell
15
Q
Is the outside or inside of the cell more negative?
A
Inside
16
Q
What is found in the extracellular fluid in terms of ions?
A
Na+,Cl-, K+ (Mostly Na+)
17
Q
Why is the inside of the cell much more negative?
A
Large negatively charged proteins cannot get out along with NaKATPase
18
Q
What is the goldman equation used for?
A
To calculate resting memberane potential
19
Q
What is the electrochemical gradiet?
A
Electrical gradient (electrical difference) + Chemical gradient (Ion concentrarion difference)
20
Q
What is the permeability of a membrane dependent on?
A
opening of channels
21
Q
T/F K+ is higher outside the cell or inside?
A
F -Na+ is higher outside the cell
22
Q
At rest, are the Na+ channels open or closed?
A
Closed, cell membrane has low permeability
23
Q
At rest, what can go inside and outside a cell?
A
K+
24
Q
What initiates an action potential?
A
Depolarization to a threshold and then Na+ goes in.
25
At what voltage do Na+ channels close?
+50
26
What is the threshold of depolarization?
-65
27
What if extracellular K+ increased?
Hyperkalemia
28
How would the electrochemical gradient for K+ be affected if extracellular K+ increased?
K+ has more driving force to move inside a cell
29
What would happen to the resting membrane potential if K+ increased extracellularly?
It would decrease, Become less negative and move closer to zero
30
What would happen to the action potential if K+ increased extracellularly?
It would move closer to threshold and more likely to occur
31
What is Hyponatremia?
Decrease in Na+ outside the cell
32
How would the electrochemical gradient for Na+ be affected if extracellular Na+ decreased?
Less driving force to move in
33
How would the resting membrane potential for Na+ be affected if extracellular Na+ decreased?
Nothing woukld happen
34
What would happen to the action potential if Na+ decreased extracellularly?
smaller action potential
35
What might happen to water balance inside the cells if extracellular Na+ decreased?
Acute water intoxication-Too much Na+ going in the cell
36
What is acute water intoxication caused by?
hyponatremia
37
Where is Glycocalyx located?
On the extracellular surface of cells
38
T/F the extracellular matrix is part of the cell
F but secreted by cells that interact with it
39
What is glycolayx made of?
Glycoproteins and Glycolipids
40
What is a glycolipid or glycoprotein?
Polysaccharides attached to proteins or lipids associated with the membrane
41
Is a glycoprotein a polypeptide?
Yes, attached to a polysaccharide
42
What are glycoproteins structure?
there is an amino acid sequence on the protein portion and monosaccarides combo of polysacc
43
Which portion is associated with the membrane in glycoproteins?
The protein portion
44
What portion of the glycoprotein gives height ansd thickness?
The saccharide portion
45
What are glycolipids made of?
polysaccahrides bound to membrane lipids
46
Is there branching in glycolipids?
Yes combinations of monosaccarides
47
What are the most complex glycolipids?
gangliosides
48
What do gangliosides do?
Receptors for bacterial toxins
49
T/F Glycocalyx is a protective barrier
True-prevents bacterial invasion
50
what is the function of glycolayx?
Differentiate organisms own tissue from transplanted tissues and cells, protective barrier and intercellular adhesion (tissue formation and blood clot)
51
What are some exmples of glycocalyx?
Blood group antigens, digestive enzymes, Avain Flu receptor
52
What are human blood group antigens?
A,AB and O (O is the universal donor) A is an O with another sugar
53
What are M cells?
Antigen sampling cells where glycolaxyx is shorter and sparser making them more sucesptible to salmonella.
54
What does H5N1 attach to?
A specific glycoprotein found in the mid region of avain lungs and deep in the human lungs
55
What is the extracellular matrix?
the stuff the cell sits in
56
T/F The ECM takes up more volume then cells do
T
57
Where is the ECM most prominent?
Connective tissue,and even more plentiful than cells.
58
What are the components of the ECM in connective tissue?
Fibers, Glycose amikno glycans (GAGS), and other proteins
59
What are GAGS attached to?
Proteoglycans
60
Where are GAGS found?
Connective tissue
61
What are proteoglycans made of?
Protein Core with Carbohydrate chains attached to make a GAG.
62
T/F There is a variable number of GAG chains in a proteoglycan
T
63
What determines the function of proteoglycans?
Associated GAG chains
64
What are the function of proteoglycans?
Attract water to provide a well hydrated matrix, withstand compressive foreces,cell migration during development and repair,
filteration,binding sites and attachment to fibrous elements
65
Where are proteoglycans found?
ECM of connective tissue
66
Where is hyaluronic Acid Found?
ECM in the dermis of the skin
67
What is the function of Hyaluroic Acid?
It pulls in water to help plump the skin
68
Why are shar peis wrinkly?
Overproduction of hyaluronic Acid
69
What fibers are found in the ECM?
Collagen and elastin
70
How many types of collagen are there?
16
71
T/F do different tissues have different types of collagwen?
Yes
72
Is collagen a protein?
Yes, its a fibeal made of collagen molecules
73
Where is collagen synthesized?
Inside a cell
74
Where does ollagen assemble.
Outside a cell into a fibril
75
What is the function of collagen?
Gives tissue strength and its arrangement determines amount of force
76
Where can very strong collagen fibers be ffound?
In ligaments (strong in 1 direction)
77
What causes Ehlers Danlos syndrome?
Defect in collagen synthesis causing cutis hyperelastica
78
What are elastic fibers made of?
A network of elastin molecules
79
T/F Elatic fibers are coiled when relaxed
T but shows crosslinking when stretched
80
What is the function of elastic fibers?
Tissue elasticity
81
Where are elastin fibers found?
Skin, Aorta, Lung
82
What is elastin broken down by?
Elastase
83
What is the breakdown of ellastic fibers essential for?
Tissue remodeling
84
What condition confers excessive elastase production in the alveloli?
Emphysema
85
T/F Intracellular signaling parhways only take one step
False-They are multistep
86
T/F intracellular signaling pathways are the cause of allergic reactions to the same molecule in two diiferent tissues
True
87
T/F Intracellular signaling pathways prevdnt disease and prevent things from going wrong
False
88
T/F opening and closing of channels and changes in membrane permeability only takes seconds after pertubation
T
89
T/F Transcrptional events take weeks
False, They take hours
90
How long does signaling take to start phosphorylation?
Minutes
91
What does signaling tell cells to do?
Survive, Divide, Differentiate, die
92
What makes up a signaling cascade?
Receptor,
Relayer, Second Messengers/Effectors
Target Protein
93
```
Which are cell surface receptors?
A. Membrane Channels
B. G-Protein Coupled Receptors
C. Enzyme linked Receptors
D. Histone Receptors
E. Pattern Recognition Receptors
F. Cytokine Receptors
G. All of the Above
E. A,B,C,E,F
```
E.
94
How does a ion channel linked receptor work?
A signal molecule comes through and binds to open the channel
95
How does a G protein linked receptor work?
A g protein comes along and binds to the receptor and a signal molecule binds. The G protein then binds to the enzyme activating it.
96
T/F a dimer bind to a catalytic domain in an enzyme linked receptor
T
97
What type of cell surface receptor is involved in innate immunity?
Pattern recognition receptors-Toll like receptors
98
Where can toll like receptors be found
On the surface of a cell as pattern recognition receptors or on the endosome inside the cell
99
How are molecular switches turned on?
Kinase through phosphorylation
| GTP Binding Protein (3 phos)
100
T/F GDP turns a signal on
F, it turns it off
101
What do GPCR's bind?
Trimeric G proteins
102
What binds to activate a G protein coupled receptor?
GTP (Alpha Beta or gamma subunit)
103
What is the function of the subunits in GPCR's?
They activate different second messengers
104
How many Histamine receptors are there?
4
105
What determines the sensitivity of a tissue to histamine?
What type of receptor on the cell
106
Where is histamine most abundant?
Skin, GI, Lungs
107
What is the source of histamine in an allergic response?
Mast cells
108
What does histamine affect that display symptoms of an allergic reaction?
Blood Vessels (increased blood flow, vascular permeability and vasodilation)
109
Which Histamine Receptor is Responsible for Allergic Reactions?
H1
110
What is the H2 receptor responsible for?
gastric acid secretion
111
Where is the H1 receptor found?
smooth muscle and endothelial cells
112
What does the H4 receptor do?
regulation of immune response
113
What does the H3 receptor do?
modulates neurotransmission
114
What causes the itching in hives?
Mast cell degranulation
115
What is H1 coupled with and what becomes activated?
Gq alpha subunit which then activates
| phospholipse C-Beta
116
What comes binds to the Gq subunit for activation?
GTP
117
What does Gq activate?
Phospholipse C and IP3 pathways
118
What are the products of the cleaved PLC-beta?
PI 4,5 bis phosphate and diacylglycerol
119
Where does the IP3 bind to its receptor?
Endoplasmic reticulum-Ca+ is released to the cytosol
120
T/F diacylglycerol is a second messenger
T-it activates PKC which phosphorylates
121
How many subunits does a G protein have?
7
122
How many subunit parts do enzyme coupled receptors have?
1
123
How do RTKs become activated?
A ligand binds to receptor exracellular and on the cystolic side tyrosine side chains phosphorylate relaying signals in the cell.
124
T/F After a ligand binds to a RTK it dimereses causing two domains to cross phosphorylate
True
125
What does cross phosphorylation on RTKs do?
Signaling complex or complete activation
126
How is Ras activated?
GTP binds
127
What does ras activate?
MAP kinase cascade to activate growth hormone via a cascade
128
What are the targets of MAP kinase?
Protein X and Y and Gene regulatory protein A and B
129
What do proteins X and Y signal?
Change in protein activity
130
What do gene regulatory protein A and B do?
Change in gene expression
131
What does NF-kappa B control?
Transcription of DNA, cell survival and cytokine production.
132
Is NF-Kappa B a transcription factor?
Yes and does not require protein synthesis
133
What does NF Kappa B depend on to become activated?
Degradtion of IKB kinase
134
What is Jak/Stat pathway?
STAT is a transcription factor and Jaks goal is to phosphorylate STAT.
135
Name the types of intercellular pathways
endocrine,paracrine, contact dependent, and synaptic
136
What is the growth hormone?
Somatotropin
137
Where is somatotropin produced?
Anterior pituitary gland
138
What does somatotropin act through?
Growth hormone receptor
139
What are the target organs for growth hormone?
Liver, Bone Growth, release of fatty acids, skeletal muscle
140
What does human growth hormane deficiency do?
decreases fat and prevents loss in muscle mass
141
Where are STAT Proteins located?
cytosol
142
What activates the Jak/STAT pathway?
cytokine receptors, growth hormone and proclactin
143
What phosphorylates STAT?
Jaks
144
What type of receptor does growth hormone bind to?
enzyme linked
145
Where iks IGF-1 synthesized?
Liver as a growth hormone
146
Do large or smaller dogs have higher levels of IGH-1
larger
147
What does Bovine Somatotropin do?
stimulate IGF-1 production in the liver, survival of mammary alveolaar cells
148
What is Cyclic AMP?
cAmp - second messenger
149
What enzyme makes cyclic amp?
adenyl cyclase
150
What does cAMP activate?
protein kinase A (PKA)
151
what are caspases?
conserved cysteine proteases
152
What initiates programmed cell death?
initiator caspases
153
what is an executioner caspase?
Mass proteolyses leading to apoposis
154
What leaks into the cytoplasm from the mitochondra? in the extrinsic pathway?
Cytochrome C
155
What activates the intrinsic pathway?
Oxidative stress, hypoxia, nutrient deprivation
