cells and immune system Flashcards
(300 cards)
1
Q
Eukaryotic cells - .
A
Cells that contain membrane-bound organelles and have DNA enclosed in a nucleus
2
Q
Cell-surface membrane -
A
Selectively permeable membrane that controls the passage of substances in and out of the cell.
3
Q
Nucleus -
A
Holds genetic information which codes for polypeptides
site of DNA replication and transcription.
4
Q
Ribosome -
A
Made of ribosomal RNA and protein site of protein synthesis (translation).
5
Q
Rough endoplasmic reticulum (rER) -
A
Has ribosomes on its surface synthesises proteins
6
Q
Smooth endoplasmic reticulum (sER) -
A
Synthesises and processes lipids including cholesterol and steroid hormones.
7
Q
Golgi apparatus -
A
Modifies proteins and lipids
packages them into vesicles
8
Q
Golgi vesicles -
A
Transports proteins and lipids to their required destination such as the cell-surface membrane.
9
Q
Lysosomes -
A
Release hydrolytic enzymes to break down pathogens or worn-out cell components.
10
Q
Mitochondria -
A
Site of aerobic respiration
produces ATP for energy release.
11
Q
Chloroplasts -
A
Absorb light energy for photosynthesis
producing organic substances.
12
Q
Cell recognition - Involves molecules
A
Involves molecules receptors
13
Q
Transport across cell membranes -
A
Refers to the movement of substances in and out of cells through the cell membrane.
14
Q
Pathogens -
A
Microorganisms that can cause disease.
15
Q
Hydrolytic enzymes -
A
Enzymes that catalyze the breakdown of compounds by adding water.
16
Q
ATP -
A
Adenosine triphosphate the energy currency of the cell.
17
Q
Polypeptides -
A
Chains of amino acids that make up proteins.
18
Q
Transcription -
A
The process of copying a segment of DNA into RNA.
19
Q
Translation -
A
The process of synthesising proteins from mRNA.
20
Q
Nucleolus -
A
A structure within the nucleus that makes ribosomes and rRNA.
21
Q
Vesicles -
A
Small membrane-bound sacs that transport materials within the cell.
22
Q
Glycoproteins -
A
Proteins that have carbohydrates attached to them modified in the Golgi apparatus.
23
Q
Glycolipids -
A
Lipids that have carbohydrates attached to them also modified in the Golgi apparatus.
24
Q
Cell wall in plants -
A
Composed mainly of cellulose (a polysaccharide) in plants / algae.
25
Cell wall in fungi -
Composed of chitin (a nitrogen-containing polysaccharide) in fungi.
26
Function of the cell wall -
Provides mechanical strength to cell and prevents cell changing shape or bursting under pressure due to osmosis.
27
Function of the cell vacuole in plants -
Maintains turgor pressure in cell (stopping plant wilting) and contains cell sap that stores sugars amino acids
28
Tissue -
Group of specialised cells with a similar structure working together to perform a specific function often with the same origin.
29
Organ -
Aggregations of tissues performing specific functions.
30
Organ system -
Group of organs working together to perform specific functions.
31
Prokaryotic cells -
Cytoplasm lacking membrane-bound organelles so genetic material not enclosed in a nucleus.
32
Eukaryotic cell -
Has membrane-bound organelles such as mitochondria and endoplasmic reticulum.
33
Prokaryotic cell -
No membrane-bound organelles such as no mitochondria or endoplasmic reticulum.
34
Nucleus in eukaryotic cells -
Contains DNA.
35
DNA in prokaryotic cells -
DNA is free in cytoplasm.
36
DNA structure in eukaryotic cells -
DNA is long & linear and associated with histone proteins.
37
DNA structure in prokaryotic cells -
DNA is short & circular and not associated with proteins.
38
Ribosomes in eukaryotic cells -
Larger (80S) ribosomes (in cytoplasm).
39
Ribosomes in prokaryotic cells -
Smaller (70S) ribosomes.
40
Cell wall in eukaryotic cells -
Only present in plants algae and fungi.
41
Cell wall in prokaryotic cells -
Present in all prokaryotic cells containing murein
42
Plasmids in eukaryotic cells -
Plasmids / capsule never present.
43
Plasmids in prokaryotic cells -
Plasmids flagella and a capsule sometimes present.
44
Size comparison of eukaryotic and prokaryotic cells -
Eukaryotic cells are larger overall size; prokaryotic cells are much smaller overall size.
45
Viruses -
Described as acellular and non-living because they are not made of cells have no metabolism
46
Structure of a virus particle -
General structure includes a protein coat and genetic material.
47
Acellular -
Not made of cells no cell membrane / cytoplasm / organelles
48
Non-living -
Have no metabolism cannot independently move / respire / replicate / excrete
49
General structure of a virus particle -
1. Nucleic acids surrounded by a capsid (protein coat) 2. Attachment proteins allow attachment to specific host cells 3. No cytoplasm ribosomes
50
Larger ribosomes -
80S ribosomes found in eukaryotic cells in the cytoplasm
51
Smaller ribosomes -
70S ribosomes found in prokaryotic cells
52
Cell wall
in plants and algae
53
Cell wall in prokaryotic cells -
Cell wall present in all prokaryotic cells containing murein a glycoprotein
54
Plasmids -
Small circular DNA molecules that may be present in some prokaryotic cells
55
Capsule -
A protective layer found in some bacteria that helps with adhesion
56
Flagella -
A tail-like structure that aids in the movement of some prokaryotic cells
57
DNA in prokaryotic cells -
DNA is short & circular and not associated with proteins
58
DNA in eukaryotic cells -
DNA is long & linear and associated with histone proteins
59
Common mistake:
Prokaryotes and plasmids - Not all prokaryotic cells have plasmids capsules
60
difference in bacterial capsules and viral capsules
Bacterial capsules provide protection while viral capsids protect genetic material
61
Common mistake: Prokaryotic cells and mitochondria -
Prokaryotic cells have no membrane-bound organelles including mitochondria
62
Common mistake: Viruses and reproduction -
Viruses are acellular and cannot reproduce on their own
63
Common mistake: Lipid envelope in viruses -
Not all viruses have a lipid envelope; HIV does but others may not
64
Overall size of eukaryotic cells -
Larger overall size compared to prokaryotic cells
65
Overall size of prokaryotic cells -
Much smaller overall size compared to eukaryotic cells
66
Magnification -
number of times greater image is than size of the real (actual) object
67
Resolution -
minimum distance apart 2 objects can be to be distinguished as separate objects
68
Optical microscope -
Light focused using glass lenses
69
Transmission electron microscope (TEM) -
Electrons focused using electromagnets
70
Scanning electron microscope (SEM) -
Electrons focused using electromagnets
71
Optical microscope image generation -
Light passes through specimen different structures absorb different amounts & wavelengths appear darker
72
TEM image generation -
Electrons pass through specimen denser parts absorb more and appear darker
73
SEM image generation -
Electrons deflected / bounce off specimen surface
74
Optical microscope resolution limitation -
Low resolution due to long wavelength of light
75
TEM resolution advantage -
Very high resolution due to short wavelength of electrons
76
SEM resolution advantage -
High resolution due to short wavelength of electrons
77
Optical microscope specimen requirement -
Specimen = thin
78
TEM specimen requirement -
Specimen = very thin
79
SEM specimen requirement -
Specimen does not need to be thin
80
Optical microscope magnification -
Low magnification (x 1500)
81
TEM magnification -
High magnification (x 1)
82
SEM magnification -
High magnification (x 1)
83
Optical microscope living specimen capability -
Can view living organisms
84
TEM living specimen capability -
Can only view dead / dehydrated specimens as uses a vacuum
vacuum as electrons travel very slowly in air
85
SEM living specimen capability -
Can only view dead / dehydrated specimens as uses a vacuum
86
Optical microscope preparation
- Simple preparation
87
TEM preparation complexity -
Complex preparation so artefacts often present
88
SEM preparation complexity -
Complex preparation so artefacts often present
89
Optical microscope color capability -
Can show colour
90
TEM color capability -
Does not show colour
91
SEM color capability -
Does not show colour
92
Steps in magnification calculation -
1. Note formula / rearrange if necessary (I = AM)
93
Steps in magnification calculation -
2. Convert units if necessary - image and actual size must be in same unit
94
Steps in magnification calculation -
3. Calculate answer and check units required or if standard form etc. is required
95
Unit conversion for centimetre -
1/100 m / 0.01 m
96
Unit conversion for millimetre -
1/1000 m / 0.001 m
97
Unit conversion for micrometre -
1/1000000 m / 0.000001 m
98
Unit conversion for nanometre -
1/1000000000 m / 0.000000001 m
99
Eyepiece graticule measurement -
1. Line up (scale of) eyepiece graticule with (scale of) stage micrometre
2. Calibrate eyepiece graticule - use stage micrometre to calculate size of divisions on eyepiece graticule
3. Take micrometre away and use graticule to measure how many divisions make up the object
4. Calculate size of object by multiplying number of divisions by size of division
5. Recalibrate eyepiece graticule at different magnifications
100
Cell fractionation principle -
1. Homogenise tissue / use a blender
101
Cell fractionation purpose -
Disrupts cell membrane breaking open cells and releasing contents / organelles
102
Cold solution -
Place in a cold isotonic
103
Isotonic solution -
Isotonic so water doesn't move in or out of organelles by osmosis.
104
Buffered solution -
Buffered to keep pH constant to prevent enzymes from denaturing.
105
Filter homogenate -
Remove large unwanted debris such as whole cells and connective tissue.
106
Ultracentrifugation -
Separates organelles in order of density/mass by centrifuging homogenate at high speed.
107
Centrifuge process -
Remove pellet of heaviest organelle and respin supernatant at a higher speed.
108
Increasing speeds in centrifugation -
Repeat at increasing speeds until separated out each time pellet made of lighter organelles.
109
Stages of cell cycle -
1. Interphase: DNA replicates
2. Mitosis: Nucleus divides
110
Interphase -
DNA replicates semi-conservatively leading to 2 chromatids joined at a centromere.
111
Mitosis -
Nucleus divides to produce 2 nuclei with identical copies of DNA.
112
Cytokinesis -
Cytoplasm and cell membrane divide to form 2 new genetically identical daughter cells.
113
Prophase -
Chromosomes condense and become visible as 2 sister chromatids joined by a centromere.
114
Metaphase -
Spindle fibres attach to chromosomes by their centromeres and align along the equator.
115
Anaphase -
Spindle fibres shorten centromere divides
116
Telophase -
Chromosomes uncoil nuclear envelopes reform
117
Importance of mitosis -
Mitosis is important for growth repairing damaged tissues
118
Eukaryotic cells and the cell cycle -
Not all eukaryotic cells undergo the cell cycle; only those that retain the ability to divide do.
119
Tumours and cancers formation -
Tumours and cancers form when mitosis is uncontrolled.
120
Eyepiece graticule -
The eyepiece graticule spans the full field of view and requires calibration at different magnifications.
121
Stage micrometer -
A micrometre has units and is used to calibrate the eyepiece graticule.
122
why do electron microscopes provide clearer images
Electron microscopes produce clearer images due to higher resolution.
123
Resolution in microscopy -
Resolution is explained in terms of the wavelength of light/electrons.
124
Scanning Electron Microscope (SEM) -
SEM produces 3D images while all electron microscope images are black and white.
125
Mutations in DNA -
Changes in DNA / genes controlling mitosis that can lead to uncontrolled cell division.
126
Tumour -
A mass of abnormal cells formed due to uncontrolled cell division.
127
Malignant tumour -
A cancerous tumour that can spread (metastasis).
128
Benign tumour -
A non-cancerous tumour.
129
Cancer treatments -
Methods that control the rate of cell division including disrupting spindle fibre activity.
130
cancer treatment of disrupting
Spindle fibre activity -
Disruption that prevents chromosomes from attaching to the spindle by their centromere.
131
Chromatids -
Identical halves of a chromosome that are separated during anaphase.
132
Interphase -
The phase in which DNA replication occurs before mitosis.
133
Binary fission -
The method by which prokaryotic cells replicate involving replication of circular DNA and plasmids followed by division of cytoplasm.
134
Viral replication -
The process by which viruses replicate involving attachment to host cells
135
Centromere -
The region that joins sister chromatids which divides during anaphase.
136
Cytokinesis -
The cytoplasmic division that may not occur in some cells such as muscle cells
137
Mitotic index -
A calculation used to measure the proportion of cells undergoing mitosis.
138
Staining cells -
The process of applying a dye to distinguish chromosomes as they are not visible without stain.
139
Squashing cells -
The technique of pressing down on a cover slip to create a single layer of cells for visibility.
140
Root tips -
The areas where dividing cells are found and mitosis occurs.
141
Hydrochloric acid in cell preparation -
Used to soak root tips to soften the tissue before staining.
142
Toluidine blue -
A stain used for visualizing DNA in cells.
143
Apparent size of cells -
The size of cells as seen under a microscope which can be converted to actual size using the formula: actual size = size of image / magnification.
144
Centrioles -
Organelles involved in spindle formation distinct from centromeres.
145
Chromosomes -
Structures that consist of DNA and proteins which are replicated during cell division.
146
Plasmids -
Small circular DNA molecules that can be replicated independently of chromosomal DNA in prokaryotic cells.
147
Host cell -
The cell that is infected by a virus and replicates virus particles.
148
Viral proteins -
Proteins produced by the infected host cell that are necessary for assembling new virus particles.
149
Separate cells / cell walls during slide preparation -
To allow stain to diffuse into cells
To allow cells to be more easily squashed
To stop mitosis
150
Optical microscope setup -
Clip slide onto stage and turn on light
151
Optical microscope setup -
Select lowest power objective lens (usually x 4)
152
Optical microscope setup -
Use coarse focusing dial to move stage close to lens
153
Optical microscope setup -
Turn coarse focusing dial to move stage away from lens until image comes into focus
Adjust fine focusing dial to get clear image
Swap to higher power objective lens then refocus
154
Rules of scientific drawing -
Look similar to specimen / image
No sketching / shading - only clear continuous lines
Include a magnification scale (eg. x 400)
Label with straight uncrossed lines
155
Mitosis stages identification - In interphase (not mitosis)
chromosomes aren't visible but nuclei are.
156
Mitosis stages identification - In mitosis
chromosomes are visible.
157
Prophase -
Chromosomes visible / distinct →because condensing
But randomly arranged →because no spindle activity / not attached to spindle fibre
158
Metaphase -
Chromosomes lined up on equator →because attaching to spindle
159
Anaphase -
Chromatids (in two groups) at poles of spindle
160
Anaphase -
Chromatids V shaped →because being pulled apart at their centromeres by spindle fibres
161
Telophase -
Chromosomes in two sets one at each pole
162
Mitotic index -
Proportion of cells undergoing mitosis (with visible chromosomes)
163
Mitotic index formula -
Mitotic index = number of cells undergoing mitosis / total number of cells in sample
164
Reliable MI determination -
Count cells in mitosis in field of view
Count only whole cells / only cells on top and right edges →standardise counting
Divide this by total number of cells in field of view
Repeat with many / at least 5 fields of view selected randomly →representative sample
Calculate a reliable mean
165
Calculating time in mitosis phase -
Identify proportion of cells in named phase at any one time
Number of cells in that phase / total number of cells observed
Multiply by length of cell cycle
166
Fluid-mosaic model -
Molecules free to move laterally in phospholipid bilayer
167
Cell membrane structure -
Many components - phospholipids, proteins, glycoproteins and glycolipids
168
Phospholipid bilayer arrangement -
Phospholipids form a bilayer - fatty acid tails face inwards, phosphate heads face outwards
169
Intrinsic proteins -
Span bilayer eg. channel and carrier proteins
170
Extrinsic proteins -
On surface of membrane
171
Glycolipids -
Lipids with polysaccharide chains attached found on exterior surface
172
Glycoproteins -
Proteins with polysaccharide chains attached found on exterior surface
173
Cholesterol in membranes -
Restricts movement of other molecules making up membrane So decreases fluidity (and permeability) / increases rigidity
174
Cell membrane adaptation -
Phospholipid bilayer is fluid →membrane can bend for vesicle formation / phagocytosis
Glycoproteins / glycolipids act as receptors / antigens →involved in cell signalling / recognition
175
Simple diffusion process
Lipid-soluble (non-polar) or very small substances eg. O2, steroid hormones
Move from an area of higher conc. to an area of lower conc. down a conc.
176
Phospholipid Bilayer -
A double layer of phospholipids that forms the basic structure of cell membranes, restricting movement of water-soluble and larger substances.
177
Passive Transport -
Movement of substances across a membrane without the use of energy from ATP, relying solely on the kinetic energy of the substances.
178
Facilitated Diffusion -
The process by which water-soluble or slightly larger substances move down a concentration gradient through specific channel or carrier proteins.
179
Carrier Proteins -
Proteins that facilitate the diffusion of slightly larger substances by changing shape to transport the substance after a complementary substance attaches to a binding site.
180
Channel Proteins -
Proteins that facilitate the diffusion of water-soluble substances through a hydrophilic pore that may be gated.
181
Osmosis -
The movement of water from an area of high to low water potential through a partially permeable membrane.
182
Water Potential (ψ) -
A measure of how likely water molecules are to move out of a solution, with pure water having the maximum potential of 0 kPA.
183
Active Transport -
The movement of substances from an area of lower to higher concentration against a concentration gradient, requiring hydrolysis of ATP and specific carrier proteins.
184
Co-Transport -
The simultaneous movement of two different substances via a co-transporter protein, where one substance moves against its concentration gradient coupled with another moving down its gradient.
185
Example of Co-Transport -
Absorption of sodium ions and glucose by epithelial cells in the mammalian ileum, where sodium is actively transported out and glucose is co-transported in.
186
Sodium-Potassium Pump -
A pump that actively transports sodium ions out of epithelial cells, establishing a concentration gradient.
187
Concentration Gradient -
The difference in the concentration of a substance across a space, affecting the rate of diffusion.
188
Surface Area -
The area of the cell membrane that can affect the rate of movement across membranes; increasing surface area increases the rate.
189
Channel Saturation -
A condition where increasing concentration gradient increases the rate of facilitated diffusion until all channel or carrier proteins are in use
190
Water Potential Gradient - .
The difference in water potential across a membrane, where increasing the gradient increases the rate of osmosis
191
Hydrolysis of ATP -
The process of breaking down ATP into ADP and Pi, releasing energy necessary for active transport.
192
Epithelial Cells -
Cells lining the mammalian ileum that absorb nutrients through various transport mechanisms.
193
Hydrophilic Pore -
A channel within channel proteins that allows the passage of water-soluble substances.
194
Gated Channels -
Channel proteins that can open or close to regulate the passage of substances.
195
Binding Site -
A specific location on a carrier protein where a complementary substance attaches before transport.
196
Limiting Factor -
A condition that restricts the rate of a process, such as the saturation of channel or carrier proteins during facilitated diffusion.
197
Specialised Cells Adaptations -
Structural modifications in certain cells that enhance the rate of transport across their membranes, such as increased surface area.
198
Kinetic Energy -
The energy that substances possess due to their motion, which drives passive transport.
199
Concentration Gradient in Active Transport -
The movement of substances against their concentration gradient, requiring energy input.
200
Microvilli in ileum -
Increase in surface area
201
Protein channels / carriers -
For facilitated diffusion (or active transport - carrier proteins only)
202
Large number of mitochondria -
Make more ATP by aerobic respiration for active transport
203
Thin cell membranes -
Cell membranes are less than 5nm wide and vary very little in thickness. A thin layer of cells increases the rate of diffusion
204
Small molecules in simple diffusion -
The key marking point here is that these molecules are lipid-soluble / non-polar.
205
Active transport proteins -
Active transport only uses carrier proteins.
206
Cholesterol in membranes -
Cholesterol decreases fluidity / increases rigidity, but this is not the same as increasing strength.
207
Osmosis definition -
Osmosis at A Level should be described in terms of water potential.
208
Diffusion definition -
Diffusion is movement from high concentration to low concentration, not gradient to gradient.
209
Adaptation for fast facilitated diffusion -
For a membrane to be adapted for rapid transport, it must have more of these proteins, rather than them just being present.
210
Dilution calculation formula -
Use the formula: C1 x V1 = C2 x V2
C1 - Concentration of stock solution
C2 - Concentration of solution you are making
V1 - Volume of stock solution used to make new concentration
V2 - Volume of new solution you are making
211
Worked example for dilution -
Volume of stock solution required, V1 = (C2/C1) x V2
212
Blotting dry plant tissue
Blot dry to remove excess water before weighing
Solution on surface will add to mass (only want to measure water taken up or lost).
213
Calculate % change in mass
(final - initial mass)/ initial mass
214
Graph plotting -
Plot a graph with concentration on x axis and percentage change in mass on y axis (calibration curve)
215
Identifying water potential -
Identify concentration where line of best fit intercepts x axis (0% change)
216
Finding water potential -
Use a table in a textbook to find the water potential of that solution.
217
Why calculate % change in mass?
Enables comparison / shows proportional change as plant tissue samples had different initial masses.
218
Water moved into cells by osmosis when
when water potential of solution is higher than inside cells.
219
Water moved out of cells by osmosis when
when water potential of solution is lower than inside cells.
220
No net gain/loss of water by osmosis when
when water potential of solution equals water potential of cells.
221
Semi-quantitative measurement -
Use a known concentration of extract & distilled water to prepare a dilution series (colour standards).
222
Quantitative measurement -
Measure absorbance (of light) of known concentrations using a colorimeter.
223
High absorbance on colorimeter
More permeable / damaged as more pigment leaks out making surrounding solution more concentrated (darker).
224
Effect of temperature on permeability
As temperature increases, permeability increases due to phospholipids gaining kinetic energy and fluidity increasing.
225
Effect of high temperatures on proteins
Transport proteins denature at high temperatures as hydrogen bonds break, changing tertiary structure.
226
Effect of low temperatures on permeability
At very low temperatures, permeability increases due to ice crystals forming which pierce the cell membrane.
227
Effect of pH on permeability -
High or low pH increases permeability as transport proteins denature as hydrogen / ionic bonds break, changing tertiary structure.
228
Effect of lipid-soluble solvents
As concentration increases, permeability increases; ethanol may dissolve phospholipid bilayer, forming gaps.
229
Antigen -
Foreign molecule / protein / glycoprotein / glycolipid that stimulates an immune response leading to production of antibody.
230
.
Cell-surface membrane -
.
Cell-surface membrane - A membrane that surrounds the cell and contains specific molecules that identify the cell.
231
Cell wall -
A rigid layer that provides structural support and protection to the cell.
232
Pathogens -
Disease causing microorganisms such as viruses, fungi, and bacteria.
233
Phagocytosis -
A non-specific immune response where a phagocyte engulfs a pathogen
234
Phagocyte -
A type of cell that engulfs and digests foreign particles and pathogens.
235
Lysosome -
An organelle that contains hydrolytic enzymes for digesting cellular waste and pathogens.
236
Antigen presenting cells -
Cells that display foreign antigens on their surface to stimulate an immune response.
237
T lymphocytes -
A type of white blood cell that plays a central role in the cellular immune response.
238
Cytotoxic T cells -
T cells that kill infected or tumor cells by producing perforin.
239
B lymphocytes -
A type of white blood cell that is responsible for the humoral immune response.
240
Clonal selection -
The process by which specific B lymphocytes are activated and proliferate in response to an antigen.
241
B plasma cells -
B cells that secrete large amounts of antibodies in response to an antigen.
242
B memory cells -
B cells that remain in the blood for a faster response during a secondary immune response.
243
Antibodies -
Quaternary structure proteins secreted by B lymphocytes that bind specifically to antigens.
244
Antigen-antibody complex -
A complex formed when an antibody binds to its specific antigen.
245
Agglutination -
The clumping of pathogens caused by antibodies binding to multiple antigens.
246
Primary immune response -
The immune response upon first exposure to an antigen, characterized by slow antibody production.
247
Secondary immune response -
The immune response upon subsequent exposure to an antigen, characterized by rapid and high concentration antibody production.
248
Vaccine -
An injection of antigens from attenuated pathogens that stimulates the formation of memory cells.
249
Specific B lymphocyte -
A B cell that has a receptor complementary to a specific antigen.
250
T helper cell -
A type of T cell that helps activate B cells and cytotoxic T cells.
251
Cytokines -
Signaling molecules released by T helper cells to stimulate B cells.
252
Mitosis -
The process of cell division that results in two identical daughter cells.
253
B memory cells -
Cells that rapidly divide by mitosis to produce B plasma cells upon secondary exposure to an antigen.
254
B plasma cells -
Cells that release antibodies faster and at a higher concentration.
255
Herd immunity -
A large proportion of the population vaccinated, reducing the spread of a pathogen.
256
Active immunity -
Immunity resulting from initial exposure to an antigen, such as a vaccine or primary infection.
257
Passive immunity -
Immunity acquired without exposure to an antigen, such as antibodies introduced from another organism.
258
Antibody production -
The process where B plasma cells produce and secrete antibodies.
259
Antibody introduction -
The transfer of antibodies from another organism, such as through breast milk or across the placenta.
260
Antigen variability -
The change in shape or tertiary structure of antigens on pathogens due to gene mutations, creating new strains.
261
HIV particle structure -
The composition of a virus that includes proteins and genetic material necessary for infection.
262
HIV replication in helper T cells -
The process by which HIV attaches to helper T cells, releases its genetic material, and uses the host cell's machinery to replicate.
263
Symptoms of AIDS -
Result from HIV infecting and killing helper T cells, leading to a deteriorated immune system.
264
Antibiotics and viruses -
Antibiotics are ineffective against viruses because viruses lack metabolic processes and structures that antibiotics target.
265
Monoclonal antibody -
An antibody produced from genetically identical or cloned B lymphocytes or plasma cells.
266
Medical treatment with monoclonal antibodies -
Monoclonal antibodies bind to specific cells, delivering therapeutic drugs attached to them.
267
Blocking antigens with monoclonal antibodies -
Monoclonal antibodies designed to block antigens or receptors on specific cells.
268
Medical diagnosis with monoclonal antibodies -
Monoclonal antibodies used to detect specific receptors or proteins associated with a diagnosis.
269
Antigen-antibody complex - .
The formation that occurs when an antibody binds to its specific antigen
270
Vaccine -
A substance used to stimulate the production of antibodies and provide immunity against one or several diseases.
271
Opportunistic infections -
Infections that occur more frequently and are more severe in individuals with weakened immune systems
272
.
Cytotoxic T cells -
.
A type of T cell that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.
273
Phagocytes -
Cells that engulf and digest pathogens and debris.
274
Antibody hydrolysis -.
The breakdown of antibodies by enzymes such as endopeptidases, exopeptidases, or dipeptidases
275
New flu vaccines -
Vaccines developed annually to combat the changing strains of the influenza virus.
276
HIV mRNA -
The messenger RNA that is transcribed from viral DNA and translated into new HIV proteins.
277
Direct ELISA -
A method where a sample with potential antigens is attached to a well, followed by the addition of complementary monoclonal antibodies with enzymes attached, which bind to antigens if present.
278
Sandwich ELISA -
A method where specific monoclonal antibodies are attached to a well, followed by the addition of a sample with potential antigens, then complementary monoclonal antibodies with enzymes attached are added to bind to antigens if present.
279
Indirect ELISA -
A method where specific antigens are attached to a well, followed by the addition of a sample with potential antibodies, then complementary monoclonal antibodies with enzymes attached are added to bind to antibodies if present.
280
Control Well Purpose -
To compare to the test to show only the enzyme causes the colour change and to ensure all unbound antibodies have been washed away
281
Ethical Issues in Vaccines -
Concerns include pre-clinical testing on animals, potential stress or harm, clinical trials on humans with potential side effects, and the risk of vaccines leading to high-risk activities.
282
Sample Size Consideration -
Was the sample size large enough to be representative?
283
Diversity of Participants -
Were participants diverse in terms of age, sex, ethnicity, and health status?
284
Placebo Control Groups -
Were placebo/control groups used for comparison?
285
Study Duration -
Was the duration of the study long enough to show long-term effects?
286
Double-Blind Trial -
Was the trial double-blind to reduce bias?
287
Observed Side Effects -
What side effects were observed, and how frequently did they occur?
288
Statistical Test Usage -
Was a statistical test used to see if there was a significant difference between start and final results?
289
Standard Deviation Importance
- Was the standard deviation of final results large, showing some people did not benefit?
290
Dosage Evaluation -
What dosage was optimum? Does increasing dose increase effectiveness enough to justify extra cost?
291
Cost of Production -
Was the cost of production and distribution low enough?
292
Lysosomes vs Lysozymes -
Lysozymes are enzymes found in lysosomes.
293
Phagocytosis Terminology -
During phagocytosis, pathogens are contained in a vacuole, which is sometimes referred to as a vesicle or phagosome.
294
Lysosomes Function --
Lysosomes fuse with the phagosome that contains the pathogen.
295
B and T Lymphocytes Specificity -
B and T lymphocytes are highly specific due to the wide range of receptors found on their cell-surface membranes
296
.
Antibody vs Enzyme -
An antibody has a binding site, while an enzyme has an active site.
297
HIV Replication -
HIV replicates using the T helper cells' transcription and translation machinery.
298
Monoclonal Antibody Definition -
A monoclonal antibody is produced by a clone of a plasma cell.
299
endopeptidase
Break peptide bonds in the middle of polypeptides to produce smaller polypeptides
300
exopeptidase
breaks peptide bonds at the ends of polypeptide to produce dipeptides or individual amino acids
