Cell Phys Exam 1 Flashcards
(219 cards)
1
Q
What is “The Cell”
A
the basic structural and functional unit of life.
2
Q
The world is made up of ______ & ______.
A
Matter & Energy
3
Q
What is the function of science?
A
to uncover natural order and explain it
4
Q
What is the Cell Docterine?
A
The cell is the basic unit of life.
5
Q
What is a microcosm?
A
A world within a world
6
Q
What is within the cell boundary?
A
chemical activity and flow of energy
7
Q
Can a chemically quiesent cell be alive?
A
NO
8
Q
Who was the first person to discover cells and coined the term “cell”.
A
Robert Hooke
9
Q
Who categorized single celled organism and the first to see bacteria?
A
Leeuwenhoek
10
Q
What are the 3 major parts to the cell theory?
A
- All animals and plants are composed of cells. (Schleiden and Schwann)
- Each cell can live in the absence o others
(Schleiden and Schwann)
3.All cells arise from pre-existing cells. (Virchow)
11
Q
What is the dense central area they call in a cell?
A
The Nucleus
12
Q
What is the area around the nucleus in a cell called?
A
The Cytoplasm
13
Q
What did Altmann discover?
A
Mitochondria
14
Q
What did Cajal discover?
A
Neurons
15
Q
What did Golgi discover?
A
The Golgi Apparatus
16
Q
What did Palade and Porter discover?
A
Methods of electron microscopy.
17
Q
What did Huxley discover?
A
show the cytoskeleton and protein filaments in muscle
18
Q
What did Watson, Crick and Wilkins discover?
A
DNA
19
Q
What did Robertson discover?
A
He purposed the cell membrane as a lipid bilayer structure.
20
Q
All Cells have:
A
- Plasma Membrane
- Metabolic Machinery
- Set of Genes
21
Q
Metabolic Machinery converts raw materials into need substances by what?
A
- Catabolism- break down
- Anabolism- build up
22
Q
An unspecialized cell changing to a specialized cell is called?
A
Cell differentiation
23
Q
The Hierarchy of organized structure:
A
- Cells aggregate to form tissue
- Tissues organize to form organs
- Organs link together to form organ systems
24
Q
What are the 4 cell categories?
A
- Muscle Cells
- Nerve Cells
- Epithelial Cells
- Connective tissue Cells
25
Muscle Cells
produce force and movement
26
Nerve Cells
initiate and conduct electrical signals
27
Epithelial Cells
form a barrier, absorption and or secretion
28
Connective Tissue Cells
connect, anchor & support
29
What are the 10 organ systems?
1. Circulatory
2. Respiratory
3. Digestive
4. Urinary
5. Musculoskeletal
6. Immune
7. Nervous
8. Endocrine
9. Reproductive
10. Integumentary
30
Circulatory
To move blood throughout the body
31
Respiratory
To exchange O2 & CO2
32
Digestive
To break down and absorb organic nutrients
33
Urinary
To regulate body fluids by excreting salts, water & nitrogenous wastes
34
Musculoskeletal
To protect, support an move the body; produce blood cells
35
Immune
Defense; return extracellular fluid to blood; form WBC's
36
Nervous
Regulate & coordinate many body activities; states of consciousness, learning an cognition; sensory
37
Endocrine
Regulate and coordinate many body activities
38
Reproductive
Produce sperm, ova and new individuals
39
Integumentary
Protection from injury dehydration, foreign invaders; regulate temperature
40
What are the 2 types of Prokaryotes?
- Eubacteria
| - Archaebacteria
41
What is Eubacteria?
most bacteria and blue-green algae
42
What is Archaebacteria?
methanovacteria, halobacteria, sulfobacteria, thermoacidophiles
43
What is Mycoplasma?
```
A genus of Kingdom: Bacteria
- lack a cell wall so are unaffected by antibiotics that target the cell wall
- Smallest of all free- living cells
Examples: M.pneumoniae
M. genitalium
```
44
What are Eukaryotes?
- has a "true" nucleus
- have mitotic spindles for mitosis
- can have mechanisms for movement that are complex
- complex genetic make-up and specific organelles fro cellular functions
- live independently or exist in multicellular organisms
45
What are units composed of microtubules?
Centriole, cilia, flagella
46
What organelles do not have a membrane?
ribosomes, nucleolus
47
What organelles are enclosed by a single membrane?
lysosome ( peroxisome, glyoxisome)
48
What organelles are enclosed by 2 membranes?
nucleus, mitochondria
49
What organelles have non-membranous tubular structures?
microtubules, microfilaments, intermediary filaments
50
What organelles have membranous tubular structures
Endoplasmic reticulum & Golgi Complex
51
Which one is not an organelle DNA thread?
Chromatin
52
What are the similarities of Prokaryotes and Eukaryotes?
- Genetic material is DNA
- A membrane surrounds the cell
- Ribosomes found in both types of cells
53
Prokaryotes:
1. No membrane around the nuclear region
2. Produce exact duplicates. (fission)
3. Simpler nutritional requirements
4. Rapid growth and division (e.g. some bacteria divide every 20 minutes)
5. Little or no membrane-bound organelles.
54
Eukaryotes:
1. double membrane separates the nucleus from the cytoplasm
2. Mitosis. Differentiate into many different kinds of cells.
3. Complex nutritional requirements.
4. Varies:
a. epithelial cells : every 24 hours
b. phagocytic cells : 2-3 weeks
c. RBC: 120 days*
d. Nerve and muscle cells do not divide after birth
5. Complex organelle system, majority of them are membrane-bound.
55
What are the two types of chemical composition?
Inorganic & Organic Components
56
Inorganic Components include:
water
salts
ions
trace elements
57
Organic Components include:
proteins, carbs, and lipids
58
What are examples of inclusions?
granules
pigment
crystals
59
What is the most common material in a living cell?
Water
60
What are two properties of water?
1. hydride of oxygen
| 2. electrically polar
61
What are the functions of water?
1. superb solvent and suspending medium
2. used to eliminate wastes
3. Participates in chemical reactions (synthesis & hydrolysis; produced during oxidation of nutrients)
4. Absorbs and releases heat slowly (temperature regulation)
5. Serves as a lubricant (mucus, synovial fluid)
62
What is calcium used for?
1. bone and teeth formation
2. muscle contraction and enzyme activities
3. blood clotting
4. effect exocrine and endocrine secretion
63
What is Calcemia?
concentration of calcium in the blood (normal 9-11 mg/dl)
64
Hypercalcemia
>normal
65
Hypocalcemia
66
Calcium Rigor
tetany (sustained muscle contraction caused by hypocalcemia)
67
Osteoporosis
low bone mineral density
68
Osteomalacia
soft bones in adults
69
What are the Functions of Phosphate?
1. formation of bones and
2. component of cell membrane (phospholipid bi-layer)
3. to make ATP
4. essential to organic compounds
5. act as a buffer
70
Chronic disorders vs. Acute Disorders
Chronic - occur in the bone
| Acute - affect muscle and nerves
71
What is functional iron?
1. hemoglobin: in RBC - most of the FE
2. myoglobin: in muscle - small amount
3. enzymes: in cells - catalase
72
What are the functions of stored iron?
1. ferritin: soluble - in liver and spleen
2. hemosiderin: insoluble - in liver and spleen
3. transferrin: protein that carries Fe - in blood (small amount of Fe/protein) - usually carried to bones.
73
What are the functions of iron?
1. Carrier of O2 & CO2
2. Role in blood formation: cells and plasma (ex. part of Hb in rbc's)
3. To produce Vitamin A (Part of Lactoferrin)
74
Who is Microcytic Anemia common in?
Females
75
If there is too much Fe in the system what can it cause?
Cancer
76
What trace element is found in Vitamin B12?
Cobalt
77
What is Macrocytic Anemia (pernicious anemia) caused by?
a Cobalt or Vitamin B12 deficiency
78
The breakdown of Copper:
- part of cytochrome oxidase system in mitochondria
- in tyrosinase: tyrosine - melanin
- needed to break down superoxides and other O2 free radicals
79
T/F: Cu deficiencies are rare in adults but more common in infants because they have low Cu storage.
TRUE
80
What is the trace element Iodine part of?
Thyroxin
81
What are the functions of Zinc?
- regulation of blood sugar
- maintenance of skin & wound healing
- necessary for sexual maturity
- cell mediated immunity
- cofactor for enzymes
82
What trace element has a glucose tolerant factor and enhances insulin binding to receptors on target cells?
Chromium
83
What are the general functions of salts and ions?
1. Regulation of osmotic pressure in the cell
2. Regulate acid-base balances in cells
3. Act as cofactors in many enzyme reactions
4. Chief supplier of ATP (chemical energy)
5. Bioelectric properties depend on electrolytes
84
What macromolecule mostly has C, H, O, N and sometimes S and P included in its makeup?
Proteins
85
What are the functions/facts of proteins?
1. Major structural materials
2. All enzymes are proteins
3. Proteins are responsible for movement
4. Transport of materials through circulatory system and across cell membranes
5. Antibodies are proteins
6. Clotting of blood requires many proteins
7. Proteins are food reserves
86
What is it called when there is high protein in the urine?
Proteinuria
87
Why are carbohydrates an important macromolecule?
- main energy source
| - structural component for cells
88
What is the primary energy source for most cells?
glucose
89
What are the 2 exceptions to the rule of glucose being the primary energy source?
- liver cells: fat supply for energy
| - heart cells - 70% energy from fat and 30% energy from carbs.
90
Type 1 diabetes can be abbreviated IDDM. What does IDDM stand for?
Insulin Dependent Diabetes Mellitus
91
What abbreviation can be used for Type 2?
NIDDM: non-insulin dependent diabetes mellitus
92
What is gestational diabetes? Is it permanent?
Glucose intolerance during pregnancy. Sometimes permanent
93
What does HbA1c stand for?
A test that measures the amount of glycated hemoglobin in the blood.
94
What type of diabetes (1 or 2) :
a. relies on supplemental insulin?
b. can be controlled with diet and exercise?
A. 1
| B. 2
95
In general, a diet lacking in ________ can lead to ketoacidosis?
Carbs
96
What is ribose found in ?
RNA
97
What is deoxyribose found in?
DNA
98
What are disaccharides created by?
dehydration synthesis
99
What are polysaccharides created by?
dehydration synthesis of 3 or more monomers
100
What are the 3 types of complex polysaccharides?
1. Neutral Polysaccharides
2. Acidic Mucopolysaccharides
3. Glycoproteins
101
proteins covalently bonded with carbs are called?
Glycoproteins
102
What are the 2 types of Glycoproteins?
1. Cellular
| 2. Secretory
103
What are the 2 functions of Glycoproteins?
1. Physiochemical properties ( ex in mucin)
| 2. Membrane interaction and recognition ( ex in glycocalyx)
104
What is Carbohydrate-deficient glycoprotein syndrome?
- cause a deficient and defective molecule
| - often serious or fatal
105
This macromolecule is hydrophobic:
Lipids
106
2 parts to the chemical composition of Lipids, they are:
1. Glycerol - 3 carbon alcohol
| 2. Fatty acids: hydrocarbons with 4-22 carbons
107
A fatty acid with no double bonds; mainly in animal fats and causes CV problems is which type?
Saturated Fatty Acids
108
A fatty acid with 1 or more double bonds; mainly in veggies and seeds; good for health
Unsaturated Fatty Acids
109
The body cannot make this type of fatty acid:
Essential Fatty Acid
110
2 Functions of Essential Fatty Acids:
1. Prevent dermatitis
| 2. Promote healing
111
What are the 3 types of glycerides?
1. Monoglyceride 1:1 FA
2. Diglyceride: 1:2 FA
3. Triglyceride: 1:3 FA
112
What are the functions of lipids?
1. Production and storage important part of energy metabolism
2. Used to make other compounds (membranes)
3. Insulation
4. To perform biological functions (transmit chemical signals into and within a cell)
113
In nucleic acids DNA is found in the _____ and RNA is found mostly in the _____.
Nucleus
| Cytoplasm
114
What are the functions of DNA?
1. Heredity
| 2. Control of cell functions
115
ATP's main function is:
Primarily an energy storage compound
116
Cyclic Adenosine Monophosphate's main function is:
Second messenger in the hormonal system
117
What is the first messenger?
Hormones
118
What are the types of inclusions of the cell?
1. Granules
2. Pigments
3. Crystals
119
Where are glycogen granules stored? Are they surrounded by a membrane? What is their function?
Stored: muscle & liver
NOT surround by a membrane
Their function is for homeostatic regulation of blood sugar
120
Where are lipid granules stored? Are they surround by a membrane? What is their function?
Stored: adipose & liver
NOT surround by a membrane
Their functions are for energy source and synthesis of membranes, structural components and steroid hormones.
121
Are secretion granules surrounded by a membrane?
Yes
122
What is a Zymogen Granule?
- contains inactive enzymes
| ex. stomach and pancreas
123
What is a Renin Granule?
- found in renal tubule cells of the kidney
124
What are the 3 types of pigments?
1. Melanin
2. Lipofuscin
3. Ferritin
125
Melanin:
- dark brown pigment stored in melanocytes
| - protects from UV radiation
126
Lipofuscin:
- light brown pigment in skin cells
| - responsible for "age spots"
127
Ferritin:
- gold-brown pigment stored in liver and spleen.
| - Iron containing storage protein is its function
128
What are the two types of Crystals?
1. Solid Crystals
- part of inorganic bony matrix
2. Liquid Crystals
- part of myelin sheath of nerves.
129
Describe the outer membrane of Mitochondria:
phospholipid bi-layer with proteins
130
Describe the intermembrane space:
between inner and outer membranes
131
Describe the inner membrane:
phospholipid bi-layer with proteins
132
Describe the cristae:
the in-foldings of the inner membrane
133
Describe the matrix
material inside the inner membrane
134
Mitochondria does something that other organelles do not...what is that?
- makes its own DNA and can also make some of the needed proteins
(still seem to obtain most of what is needed from the cell however)
135
The outer membrane contains a large number of integral membrane proteins called?
Porins
136
What do Porins allow the molecules to do?
molecules are able to pass into and out of the mitochondrion through porins.
(small molecules can diffuse freely. Large molecules (proteins) can pass if they have a specific signaling sequence which will allow transfer across the outer membrane)
137
Intermembrane Space has concentration of small molecules, this concentration is found in?
Cytoplasm
| Large membrane concentration in intermembrane space can be very different than in the cytoplasm
138
Which space contains many H+ ions?
Intermembrane Space
139
What membrane has:
- no porins
- high impermeable membrane
- transporter to enter and leave matrix
- location of ATP synthase
- Location of ETS and oxidative phosphorylation & Stage II the intermediary stage (hub reaction)
- Contain mitochondrial fusion and fission protein
Inner Membrane
140
Which membrane has folds in the inner mitochondrial membrane?
Cristae
141
What is the function of the Cristae?
1. Increase surface area to receive respiratory enzymes
| 2. Provide sites for electron transport in making ATP
142
Would you expect a high or low number of cristae in a muscle cell?
High # of cristae because they are very folded.
143
Cristae contain respiratory stalks with "studs."
| "studys"= F1 Particle= ____
Oxysome
144
What enzyme adds a Pi to ADP to make ATP
ATP synthase
145
What are the two components to ATP synthase?
Fo portion - within membrane
F1 portion - above membrane; inside the matrix
(There function is to carry products necessary for ETS)
146
What does the matrix contain?
1. Enzymes
2. Ribosomes
3. tRNA
4. Mitochondrial DNA
5. Matrix granules
147
What are the functions of the Mitochondria?
1. "Power Plants" of the cell ( converts food to chemical energy)
2. Protein Synthesis
3. Can divide by binary fission
148
What is the Symbiotic Hypothesis of Mitochondrial Origin?
- Mitochondria were once prokaryotic cells capable of oxidative mechanisms that eukaryotes could not perform. These prokaryotes became endosymbionts within eukaryotic cells.
149
Similarities between mitochondria and prokaryotes are :
1. can divide independently of cell division
2. have their own DNA and it is circular
3. DNA replicates in both
4. ribosomes in mitochondria resemble those in prokaryotes
150
What is the Autogenous hypothesis?
Mitochondria developed by the splitting of nuclear DNA at the time of eukaryotic cells "branched" from prokaryotic cells.
151
What are the sources of needed material and energy for Metabolism and Energy Transduction?
1. Carbs
2. Proteins (8 of the 20 a.a.s)
3. Lipids (certain unsaturated fats must be consumed)
4. Some vitamins (~8 or more)
152
When an energy-rich molecule is broken down into simpler molecules that are energy poor this is called?
Catabolism
153
Energy is releases so this reaction is...
Exergonic
154
When a complex molecule is built from smaller, simpler molecules this is called?
Anabolism
155
Energy is used/consumed so these reactions are...
Endergonic
156
What are the 2 types of Human Respiration?
1. External Respiration
(breathing - getting 02 into the body and C02 out of the body)
2. Cellular Respiration
(using 02 from the air to release energy from food. C02 is an end product of releasing energy in food)
157
When polysaccharides are broken down into monosaccharides this is known as:
Carb Metabolism
158
What is the Fate of Absorbed Glucose?
1. ATP production (1g produces 4 kilocalories)
2. Glycogenesis: glucose converted to glycogen in the liver
3. Lipogenesis= excess glucose being transformed in glycerol and fatty acids. ( can be used to synthesize triglycerides & occurs in liver cells and adipocytes)
4. Amino Acid Synthesis
5. Excretion in urine ( a meal high in carbs but no triglycerides)
159
Glucose is transported from blood to most cells by?
Carrier-mediated diffusion
160
What increases the rate of facilitated diffusion into most body cells (except neurons and hepatocytes)?
Insulin
161
What is it called when there is a complete oxidation of glucose?
Cellular Respiration
162
Why is this such an important process within cells? (Cellular Respiration)
- this process is the chief source of cellular energy
163
What is the 4 stage process of Glucose Oxidation?
1. Glycolysis
2. Intermediary Stage
3. Krebs Cycle
4. Oxidative Phosphorylation and Electron Transport System
164
Important points about Glycolysis:
- aerobic process can occur in cells/tissue
a. w/o mitochondria
b. w/limited 02
c. rapidly growing tumors
- 1 Glucose converted to 2 pyruvates: 10 enzymatic rxns
- If 02 present, glucose goes to the Krebs Cycle
- If 02 is not present, glucose is converted to lactate.
- Net gain of 2 ATP's: 4 produced but 2 used
- Occurs in cell cytoplasm
165
Important points about the Intermediary Stage:
- Pyruvate is converted to acetyl CoA
- 2 C02 are generated*
- H+ transferred to NAD+
- No ATP produced
- Occurs in the matrix of mitochondria
- Aerobic rxn
166
Important points about the Krebs Cycle:
-Aerobic rxn
-Occurs in the matrix of mitochondria
-2 GTP's produced (1GT/acetyl CoA)
GTP+ADP GDP+ATP
-4 CO2 produced as a final end product ( 2 C02/ acetyl CoA)
-6 NADH+6H+ & 2 FADH2 (for both acetyal CoA's) produced and will be used to transport H+ to stage 4 (ETS)
-2 turns/ 1 glucose molecule
167
Important points about the Oxidateive Phosphorylation and Electron Transport System:
- Aerobic rxn
- occurs in inner membrane of mitochondria
- Needed enzymes embedded w/in inner membrane: 2 groups
1. those that transfer H+ to 02
- most contain Fe or Cu: cytochromes
- important b/c they form the ETS (H+ initially transferred from NADH + H+ or DADH2: will finally go to 02 to get H20)
2. those that make ATP
- Electrons are shuttled between FAD, coenzyme Q and cytochromes
- 26 ATP's produced
- 12 H20 produced as an end product: results from H+ being initially transferred from NADH + H+ or FADH2 and finally combined to 02.
- Each step releases small amounts of energy so it can be used to make ATP
- Protein complexes form within inner membrane (separate from ATP synthase) function: allows H+ movement
168
What is it called when you add a phosphate to something?
Phosphorylation
169
What are the 2 methods of phosphorylation?
1. Substrate level phosphorylation
| 2. Oxidative Phosphorylation
170
Substrate level phosphorylation makes a total of ___ATP
4
171
This type of phosphorylation occurs within the ETS, requires 02
Oxidative Phosphorylation
172
How many ATP are made in Oxidative Phosphorylation?
26 ATP
| - Sum Total for ATP produced from 1 glucose = 30 ATP!!!
173
What is it called when glucose is converted to glycogen?
Glycogenesis
174
What is it called when there is a conversion of fats and protein into glucose
Gluconeogenesis
175
In Lipid Metabolism what is an example of Catabolism?
Gluconeogenesis- glycerol to glucose; 16-carbon fatty acid yields 106 ATP's
176
What process happens in Anabolism during Lipid Metabolism?
Lipogenesis- synthesis of lipids from glucose
177
During Catabolism in Protein Metabolism before a.a.s can go through the Kreb's cycle in must be "converted by what processes?
1. Deamination= removal or transfer or an amine group
2. Dehydration= removal of a hydrogen from a protein
3. Decarboxylation= removal of a carboxyl group
- Ketogenic a.a.s can be transformed into ketone bodies.
178
What are 2 examples that would prompt the formation of ketone bodies?
Uncontrolled diabetes & fasting
179
During Anabolism in Protein Metabolism protein synthesis directed by ____ ,_____ and ____ participation.
DNA, RNA, Ribosome
180
Signaling Molecules and Cell membrane receptor reactions can regulate:
1. Metabolism
2. Cellular movement
3. Proliferation
4. Differentiation
5. Survival
181
What are the 3 methods of cell signaling?
1. Endocrine Signaling
2. Paracrine Signaling
3. Autocrine Signaling
182
Signaling molecules are released into the blood stream known as:
Endocrine Signaling
183
Hormones, chemicals, growth factors, and neuropeptides are what type of molecules?
Signaling Molecules
184
What type of signaling molecule diffuse locally through extra cellular fluid to reach a near-by target?
Paracrine Signaling
185
What type of signaling cell signals itself?
Autocrine Signaling
186
Could abnormal autocrine signaling factor into cancer cell numbers increasing?
Yes
187
What has a specialized integral membrane protein ( can have 2 or more protein subunits)
Membrane Receptors
188
What is signal transduction?
extracellular ligand attaches to receptor and triggers changes in the cells functioning
189
Ligand binding outside of the cell causes what?
causes the chemical reactions/changes inside the cell
190
If the ligand is hydrophilic is the cell membrane hydrophilic or hydrophobic?
hydrophobic
191
What is a G Protein-linked Receptor?
Many types of GPLR's involved in many physiological processes.
Different types include visual sensing, taste & smell, behavioral regulation, regulation of immune functions, many ANS functions, homeostasis, various cellular activities
192
Which function of GPLR's transmit light into cellular signals?
Visual Sensing
193
What function of GPLR's deals with neurotransmitters
Behavioral regulation
194
Which function of GPLR's deals with inflammation?
Regulation of immune functions
195
Which function of GPLR's deals with blood pressure, heart rate digestion
ANS functions
196
What function of GPLR's deals with water balance
homeostasis
197
What function of GPLR's deals with enzyme activities, secretion, membrane permeability
Various Cellular Activities
198
What is an N-terminus
A GPLR structure exposed to ISF with receptor for the signaling ligand
199
Which protein contains 7 helical loops and is part of/within the cell membrane?
Integral Protein
200
What structure extends into the cytoplasm, and at the tail end we can find 3 GPLR subunits including G alpha: with a GDP/GTP binding site G beta & G gamma?
C-terminus
201
What is an enzyme-linked receptor called?
Catalytic Receptor
202
What will an integral membrane protein do?
will cause enzyme activity within the cell when a stimulatory ligand binds to the extracellular portion.
203
What type of catalytic receptor has a kinase enzyme attach a phosphate group from high energy molecules to specific target molecules?
Tyrosine-specific protein kinases
204
Insufficient signaling of epidermal growth factor receptors is accociated with ________ diseases like _____ _____ & _______ disease.
Neurodegenerative
Multiple Sclerosis
Alzheimer's
205
What is the 1st step of general signaling mechanism?
ligan binds to extracellular receptor to cause conformational change in the 2 part protein inside of cell.
206
What is the 2nd step of general signaling mechanism?
2 part protein becomes a dimer (that is unphosphorylated) - dimerization
207
What is the 3rd step of general signaling mechanism?
- Tyrosines in the catalytic receptor protein are phosphorylation using ATP's.
- Phosphorylation within the protein kin as will generally increase protein kinase activity.
208
What is the 4th step of general signaling mechanism?
-Relay proteins attach to phosphorylated dimer causing a structural change.
209
What is the 5th step of general signaling mechanism?
- Cellular response follow
- There can be many responses and they can be quite different
- Not of Interest: G proteins typically have 1 cellular response.
210
Where are channel proteins found?
in the plasma membrane and completely span the plasma membrane.
211
T/F- Channel proteins do not have receptor sites for ligands?
False; they do have receptor sites for ligands.
212
T/F - Channel proteins remain closed without ligands attached to receptors?
True
213
T/F - Channel proteins will open with ligand attachment to receptor?
True; channel typically remains open for a short time, then ligand dissociates, then channel closes.
214
What is programmed cell death called?
Apoptosis
215
What is regulated by signal transduction, involves a series of events such as nuclear and cell break up, and also has debris phagocytized?
Apoptosis
216
What are the processes in which Apoptosis occurs?
- balancing cell proliferation
- removal of webbing between digits
- Resorption of tadpole tail
- "Pruning" of neurons during infant development
- Removing dead RBC's
- Damaged DNA and other serious cell damage
217
What induces apoptosis in infected cells?
NK lymphocytes
218
What are the 4 key evens during viral infection involving apoptosis?
1. NK cells Fas protein binds to infected cells FAS receptor.
2. Receptor binding results in pro-caspases
3. Caspases cascade is initiated. proteins are cleaved.
4. Cell dies by apoptosis.
219
What is a Fas Ligand
- a transmembrane protein
- binding of Fas ligand/receptor leads to apoptosis
- play role in regulation of immune system and cancer growth.
