BIO 302 Exam 3 Flashcards
Stem Cells, Cytoskeleton
1
Q
What type of cell is produced from a stem cell?
A
A daughter cell
2
Q
What are the pathways a stem cell can go through?
A
Renewal, Differentiate, or both
3
Q
What does Totipotent mean?
A
Cells that have the potential to give rise to every cell type in the organism.
4
Q
What does Pluripotent mean?
A
Cells that have the potential to give rise to many different cells
5
Q
What does Multipotent mean?
A
Cells that have the potential to give rise to few different cell types.
6
Q
True or False
Totipotent, Pluripotent, and Multipotent cells go through cell division
A
True
7
Q
What type of stem cell don’t divide
A
Terminally differentiated
8
Q
What are terminally differentiated cells?
A
Cells that are in their final stage and can’t give rise to any other cell type.
9
Q
True or False
Bone marrow is an example of Pluripotent stem cells.
A
False, Multipotent
10
Q
What determines a cell’s fate?
A
Genome of a fertile egg
11
Q
True or False
Endoderms, Mesoderms, and Ectoderms are examples of Pluripotent cells.
A
True
12
Q
What are the components to the Blastula?
A
Trohoectoderm and Inner core
13
Q
What are part of the intestine is the stem cell?
A
Crypt
14
Q
What pathway does the crypt go through for creating more cells?
A
Wnt Pathway
15
Q
In what direction does the crypt grow cells?
A
Up
16
Q
True or False
Microvilli is an example of terminally differentiated cells
A
True
17
Q
What part of the skin is the adult stem cell?
A
Basal layer
18
Q
How does the environment play a role in stem cell division?
A
The environment refers to the signal factors and the genes expressed.
19
Q
What are the 4 cytoskeletal structures?
A
Intermediate Filament
Microtubules
Actin Filaments
Centrioles
20
Q
What is the function of the cytoskeleton?
A
Motility
Cell structure
Movement within the cell
Internal organization
Cell division
21
Q
What is the function of intermediate filament?
A
Cell shape
Internal structure
Structure of the nuclear lamina
22
Q
What is the function of microtubules?
A
Cell Shape
Pathway and transport within the cell
Cell division (spindle fibers)
23
Q
What is the function of actin filaments?
A
Cell shape
muscle contraction
cell division (cleavage furrow)
Changes in cell shape
cortex underneath outer membrane
24
Q
Intermediate filament has very high… strength
A
Tensil
25
What does intermediate filament do for the nuclear lamina
Keeps the shape of the nucleus
Acts as an attachment site for chromosomes
26
How does intermediate filament function for cell-cell junction?
Makes the junction stronger
27
Which cytoskeletal structure relieves the stress of the cells when stretched?
Intermediate filaments
28
True or False
Keratin is not the most diverse type of intermediate filament
False, it is!
29
What are the types of intermediate filaments are in the cytoplasm?
Keratin, Vimentin, and neurofilament
30
What is Epidermolysis Bullosa Simplex?
A disease of the epidermal tissue caused by the mutation of keratin
31
What is Amyotrophic Lateral Sclerosis?
Abnormality accumulation of neurofilament
32
What is Progeria?
Premature aging caused by defects in nuclear lamina
33
When lamina proteins are phosphorylated this disrupts their... thus disrupting the... thus break down of the...
1. Interaction
2. Nuclear lamina
3. nuclear envelope
34
What is the function of the KASH family of the linker protein?
Junctions that link between intermediate filaments, actin filaments, microtubules, nuclear membrane, and cytoplasm
35
What is the function of the SUN family linker proteins?
They link the nuclear lamina, nuclear membrane, and chromosomes
36
What is the function of the plectin for linker proteins?
They link proteins between desmosomes and intermediate filaments
37
What is microtubules made of?
Alpha and Beta tubulin heterodimers
38
How do microtubules serve for mitosis or meiosis?
Assist in separating chromosomes during cell division
39
What do bundled microtubules form?
Cilia
40
How many protofilaments form a tube of microtubules?
13
41
What are the 2 ends of microtubules?
Positive and negative end
42
What type of tubulin are on the positive end and what type are on the negative end?
Positive (Free alpha)
Negative (Free Beta)
43
What makes up the Microtubule Organizing Centers (MTOCs)
Centrioles=core
Gamma tubulin ring complexes
44
What is the purpose of gamma-tubulin rings?
Act as a foundation starting point for microtubule extension serving as a nucleation site
45
True or False
Microtubules grow and shrink at the same time when forming
True
46
What reaction controls the dynamic stability of a microtubule
GTP hydrolysis
47
What is the process of a growing microtubules?
Tubulin dimers bind with GTP creating a GTP tubulin_---> GTP tubulin dimers add to the growing microtubules----> This addition grows faster than GTP hydrolysis by the dimers
48
What is the process of shrinking microtubules?
When GTP-hydrolysis is faster than the addition of GTP-tubulin---> Causing the GTP cap to be lost---> the protofilaments containing GTP tubulin will peel away---> Releasing GDP-tubulin into the cytosol
49
What does Taxol do?
Binds to filaments and prevents depolymerization
50
What are the effects of Colchicine
Form a complex with tubulin dimers that bind to the end of a microtubule, preventing further polymerization
51
What are the effects of Nocodazole?
Binds tubulin dimers and prevents their polymerization
52
How many cytosols, mitochondria, and ERs are there in one cell?
Cytosol: 1
Mitochondria: 1700
ER: 1
53
How many Nuclei, Golgi Apparatus, and Peroxisomes are there in one cell?
Nucleus: 1
Golgi Apparatus: 1
Peroxisomes: 400
54
How many Lysosomes and Endosomes are there in one cell?
Lysosomes: 300
Endosomes: 200
55
What is the percentage of total cell volume of the Cytosol, mitochondria, ER, and Nuclei?
Cytosol: 54%
Mitocondria: 22%
ER: 12%
Nuclei: 6%
56
What is the percentage of total cell volume of the Nuclei, Golgi Apparatus, Peroxisomes, Lysosomes, and Endosomes?
Nuclei: 6
Golgi Apparatus: 3
Peroxisomes: 1
Lysosomes: 1
Endososmes: 1
57
What are the 3 mechanisms of Protein import into the organelles?
1. Nuclear Pore Complex
2. Transport through vesicles
3. Transport across the membrane
58
If a protein doesn't have a signal what happens to it?
Stays in the cytosol
59
If a protein does have a specific signal what happens to it?
The protein is sent to the ER then processed in the Endomembrane
60
What are the types of Endocytosis?
1. Phagocytosis
2. Pinocytosis
3. Receptor-Mediated
61
What is Phagocytosis?
Engulfment of cell and large macromolecules
62
What is Pinocytosis?
Taking in solution and dissolved solutes
63
What is Receptor-Mediated Endocytosis?
using receptor proteins on the cell surface to capture a specific target molecule
64
What are the 3 outcomes of endocytosis?
1. Recycled
2. Degraded
3. Transcytosis
65
What is the pH of a lysosome?
5.0
66
What is autophagy?
A process that delivers cellular waste to the lysosome
67
How does the lysosome keep a low pH?
It uses an ATP pump that pumps H+ to the lysosome
68
What does the ER do for misfolded proteins?
They send out sensor proteins to bind to the misfolded protein. This binding will send signals to the nucleus to synthesize chaperone proteins.
69
What other sensors increase the size of the ER
1. Enhance protein processing
2. Promote the transfer of proteins into cytosol to be degraded
3. Proteins shut down protein synthesis in the ER
70
What type of modifications are done in the ER lumen?
1. Cleavage
2. Disulfide bridge
3. Carbohydrate addition
71
What are the reasons to modify proteins?
1. Protection
2. Signal to remain in ER or Golgi
3. Transport/packaging signal
4. Become apart of the ECM
72
Where are V-snares found?
On the surface of the vesicles
73
Where are the T-snares found?
Found on the surface the target destination
74
What proteins are needed for Vesicle Transport?
Dynamin, Clatherin, Adaptin
75
What is the function of the Endomembrane System?
To synthesize and modify proteins and lipids
76
What are the outcomes of newly modified proteins and lipids?
1. To be secreted
2. To be integrated into the outer membrane
3. Endosomes
77
Where are lipids modified and synthesized?
Smooth ER
78
How many proteins are made if the nuclear pore complex?
Over 30
79
What is the function of the nuclear pore complex?
To regulate the movement of proteins in and out of the pore
80
What receptor is needed for the nuclear pore complex?
Nuclear import receptor
81
What is Ran?
A type of GTPase
82
Where is Ran GEF found?
Found in the nucleus
83
What is Ran GAP found?
Found in the cytosol
84
What proteins are needed for protein sorting in the mitochondria?
Protein of translocator in the outer membrane (TOM)
Import receptor proteins
Protein of translocator in the inner membrane (TIM)
85
What is the process of the nuclear pore complex?
The cargo protein binds with the nuclear import receptor---> This protein receptor complex---> Goes into the nuclear pore---> Once in the nucleus the protein unbinds with the receptor
86
What is the function of RAN?
To support the nuclear pore complex
87
What is the process of mitochondrial protein import?
A protein with a signal sequence binds to the import receptor protein---> This import receptor protein is bound to TOM, TOM will then slide across the outer membrane to meet TIM---> Once they meet TOM and TIM will interlock allowing the protein to enter the inner membrane---> Once in the inner membrane the signal sequence is cleaved off.
88
What proteins are involved with protein sorting of the ER?
SRP, SRP receptor, Protein translocator, Signal peptidase
89
What is the process of ER protein sorting?
A ribosome translating a protein binds with SRP---> The ribosome SRP complex binds with SRP receptor alongside with protein translocator---> The SRP unbinds with the ribosome allowing the protein to be fed through the protein translocator---> Once fed through the protein translocator the signal sequence is cleaved off by a signal peptidase fusing into the membrane.
90
What is the functions of the membrane?
1. Receive information
2. Movement and Expansion
3. Import and export of molecules
91
TRUE or FALSE
The cell membrane is hydrophobic
TRUE
92
Rank these from easily getting through the membrane to not.
1. Ions
2. Small non-polar
3. Larger uncharged
4. Small uncharged
Easily get through
1. Small non-polar
2. Small uncharged
3. Large uncharged
4. Ions
93
What's the difference between passive and active transport?
Passive: Rely on the concentration gradient
Active: Requires ATP or radiant energy
94
What does osmosis mean?
The movement of water across the membrane
95
What type of channel allows water to move through?
Aquaporins
96
What secondary structure are aquaporins?
Alpha Helices
97
What type of amino acids are on the outside of aquaporins?
Hydrophic
98
What type of amino acids are on the inside of aquaporins?
Charged polar
99
Osmosis travels from... concentration to... concentration
1. High
2. Low
100
What is it called when water balances out on both sides of the cell
Dynamic Equilibrium
101
What is happening to water in hypertonic, hypotonic, and isotonic solutions?
Hypertonic: Water leaves
Hypotonic: Moves in
Isotonic: Balances going in and out
102
What are strategies that Protozoan, animal, and plant cells use to reduce osmotic pressure?
Protozoan: Collect excess water and expel it through contracting of the vacuole
Animal: Pump out solutes/ions to make the cytoplasm more isotonic
Plant: osmotic pressure will balance out with the pressure potential of the cell wall
103
Compare and Contrast passive transport of channel and transporter.
Channel
-Very selective
- Channel stays in shape
-Can have alpha helices and beta barrels
Transporter
- Conformational changes after bound with a molecule
Similarities
-Both are dependent on concentration gradients moving from high to low
104
What are the types of active transport?
Gradient driven
ATP driven
Light driven
105
What toxin blocks Na+/K+ pump?
Ouabain
106
Does active ATP-driven transport need a specific binding site?
YES
107
What does a Na+/K+ pump create?
An electrochemical gradient
108
How does the gradient driven pump work?
They work against the concentration gradient
109
What is the difference between symporter and antiporter?
Symporter: Same direction
Antiporter: Opposite direction
110
