A LEVEL BIO REVISION Flashcards
Number
Question
1
What is a light microscope used for?
2
What are the pros and cons of a light microscope?
3
What is a laser scanning confocal microscope used for?
4
Whatis a transmission electron microscope be used for?
5
What is a scanning electron microscope used for?
6
What are the pros and cons of an electron microscope?
7
What is the difference between a transmission and an scanning electron microscope?
8
What is the difference between light and electron microscopes?
9
What is an eye piece graticule?
10
What is a stage micrometer?
11
Why do we stain specimens?
12
What is differential staining?
13
What is the formula to calculate magnification?
14
What is the formula to calculate actual object size?
15
How do we work out image size?
16
What is magnification?
17
What is resolution?
18
What are the maximum resolutions of the different microscopes?
19
What is the maximum magnification of the different microscopes?
20
What are the main structures of all eukaryotic cells?
21
What is the structure and function of the nucleus?
22
What is the structure and function of the nucleolus?
23
What is the structure and function of the nuclear envelope?
24
What is the structure and function of the rough endoplasmic reticulum (RER)?
25
What is the structure and function of the smooth endoplasmic reticulum (SER)?
26
What is the structure and function of the Golgi apparatus?
27
What is the structure and function of the ribosomes?
28
What is the structure and function of the mitochondria?
29
What is the structure and function of the lysosomes?
30
What is the structure and function of the chloroplasts?
31
What is the structure and function of the plasma membrane?
32
What is the structure and function of the centrioles?
33
What is the structure and function of the cell wall?
34
What is the structure and function of the flagella?
35
What is the structure and function of the cillia?
36
Which structures are involved in the production of proteins?
37
What is the structure and function of the cytoskeleton?
38
What do prokaryotic and eukaryotic cells have in common?
39
What is different between prokaryotic and eukaryotic cells?
40
How do prokaryotes divide?
41
List out the elements that make up proteins.
42
Explain the polar nature of water.
43
What allows water molecules to have cohesive and adhesive properties?
44
Describe the structure of amylose, including the bonds involved and the shape.
45
Describe the structure of amylopectin, including the bonds involved and the shape.
46
State the two structures that make up starch.
47
State the reaction that breaks down maltose.
48
What is the reaction to join monosaccharides together?
49
What are the 3 types of polysaccharides that α-glucose can form?
50
What are the two monosaccharides that join up to make sucrose?
51
1,6 glycosidic bonds are found on ……..
52
β-glucose can only be found in ……..
53
How are the monosaccharides in cellulose arranged?
54
Based on the arrangement of cellulose molecules, explain why cell walls provide strength and support to plant cells.
55
What does the Benedict’s test test for?
56
Explain how a positive result is formed in Benedict’s test.
57
How can we test for starch?
58
How can we use a colorimeter to do a quantitative Benedict’s test?
59
What are the two parts that make up a carboxylic acid?
60
How many water molecule(s) is/are needed when breaking down a triglyceride?
61
What is another term for the condensation reaction that makes lipids?
62
What is the difference in structure between saturated and unsaturated lipids?
63
Why do oils contain unsaturated triglycerides rather than saturated?
64
What is the difference in structure between triglyceride and phospholipid?
65
Describe the phospholipid bilayer arrangement.
66
Describe 2 similarities and 1 difference between phospholipids and sterols.
67
Describe the steps in identifying lipids and state the positive result.
68
State the monomer of a protein.
69
What are the components that make up an amino acid?
70
Name the bond formed between two amino acids.
71
What is the primary structure of a protein?
72
What is the secondary structure of a protein?
73
What is the tertiary structure of a protein?
74
What is the quaternary structure of a protein?
75
State the bond involved in the primary structure of a protein.
76
Stat the bond involved in the secondary structure of a protein
77
State the bond involved in the tertiary structure of a protein.
78
State the bond involved in the quaternary structure of a protein.
79
Name the reaction that breaks down proteins.
80
What is the solution used to test for the presence of proteins?
81
Describe a positive result for proteins.
82
What is thin layer chromatography?
83
Based on what principles are the amino acids separated in TLC?
84
Why should the chromatography plate be only handled by the edges?
85
What are the three types of proteins?
86
Explain why insulin is soluble in blood.
87
What are prosthetic groups?
88
Give an example of a conjugated protein.
89
Compare the haem groups in haemoglobin and catalase.
90
How many haem groups do a haemoglobin contain?
91
Explain why keratin is relatively strong, inflexible and insoluble.
92
Briefly describe the structure of collagen.
93
What bonds do DNA/RNA polymerase catalyse?
94
Name the monomer of a nucleic acid.
95
State the five possible bases of a nucleotide.
96
State the three components to a DNA nucleotide.
97
The two strands of the double helix are …………. to each other.
98
Thymine, cytosine and uracil belong to a group of bases. Name the group.
99
Adenine and guanine belong to a group of bases. Name the group.
100
State the complementary base pairings.
101
State the number of hydrogen bonds formed between adenine and thymine/uracil.
102
State the number of hydrogen bonds formed between cytosine and guanine.
103
Why is DNA replication described as semi-conservative?
104
State the enzymes involved in DNA replication.
105
State the function of DNA polymerase.
106
State the function of DNA helicase.
107
The free nucleotides pair up with the exposed bases on the DNA strands based on …… (which principle?)
108
DNA polymerase can only build phosphodiester bonds on the daughter strand in a particular direction. What is this direction?
109
In which direction of the template strand does the DNA polymerase move in?
110
Define ‘genetic code’.
111
The genetic code is described as ‘degenerate’. What does that mean?
112
Define ‘gene’.
113
What is a codon?
114
What are the two differences between DNA and RNA?
115
Name the enzymes involved in transcription.
116
Why is the antisense strand needed even though it does not code for proteins?
117
What type of bond does mRNA have?
118
Even though DNA codes for proteins directly, why is mRNA needed to be made for making proteins?
119
How is rRNA involved in catalysing translation?
120
Which part of tRNA binds to the mRNA?
121
Name the amino acid that is always at the start of a protein.
122
Describe what happens to the amino acid chain to make it a fully functional protein.
123
State the two stages of protein synthesis.
124
Name the product of transcription.
125
Name the product of translation.
126
State the location where translation occurs.
127
What are the three main types of activities in cells that require energy?
128
What does ‘ATP’ stand for and what is it?
129
Draw the structure of ATP.
130
How does ATP release energy?
131
State 3 properties of ATP.
132
What are metabolic reactions?
133
What are anabolic reactions?
134
What are catabolic reactions?
135
What are enzymes?
136
Name the energy that is required to start a reaction.
137
What are enzymes’ effect on the activation energy of a reaction?
138
Name the area on the enzyme that binds to and reacts with the substrate.
139
The active site has a _____ shape to the substrate.
140
Name the two models used to illustrate enzyme actions.
141
Name the structure where the enzyme and substrate are bound together.
142
What is the difference between the lock-and-key model and the induced fit model?
143
Name an intracellular enzyme.
144
Name an extracellular enzyme.
145
Define the term ‘denaturation’.
146
Explain how an increase of temperature increases enzyme activity.
147
Explain how high temperatures can denature enzymes.
148
What is the temperature coefficient (Q10)?
149
How are the enzymes in organisms that live in cold environments adapted?
150
How are the enzymes in organisms that live in hot environments adapted?
151
How does a change in pH affect enzyme structure?
152
Explain why an increase in substrate concentration increases rate of reaction.
153
What does it mean by a ‘reversible’ inhibitor?
154
Most competitive inhibitors are reversible or irreversible?
155
Explain how Vmax of the enzyme can be unchanged in competitive inhibition.
156
What types of inhibitor does aspirin belong to?
157
Explain the difference between competitive and non-competitive inhibition mechanisms.
158
Explain how an increase in substrate concentration affects the rate of reaction in non-competitive inhibition.
159
State two examples of irreversible, non-competitive inhibitors for human use.
160
What is end-product inhibition?
161
How does ATP regulate its own production by end-product inhibition?
162
State the difference between cofactors and coenzymes.
163
From which chemical are cofactors derived from?
164
From which chemical are coenzymes derived from?
165
Name the cofactor found in amylase.
166
Name the cofactor invovled in photosynthesis.
167
Name the cofactor invovled in respiration.
168
State the difference between cofactors and prosthetic groups.
169
Name the prosthetic group in haemoglobin.
170
Name the prosthetic group in carbonic anhydrase.
171
What are the three ways that an enzyme can be activated by changing the tertiary structure?
172
Why is it important that some enzymes are produced in its inactive form?
173
What is an apoenzyme?
174
What is a holoenzyme?
175
What is the fluid mosaic model?
176
What is a glycolipid?
177
What is a glycoprotein?
178
State four functions of membranes at the surface of cells
179
State 3 functions of membranes within cells
180
The principal design of the plasma membrane consists of two layers; what name is given to these two layers?
181
Explain the orientation of phospholipids within the bilayer
182
Describe the function of glycoproteins and glycolipids in the phospholipid bilayer
183
Give 3 examples of intrinsic proteins
184
Channel proteins and carrier proteins have what main role within the membrane?
185
Describe the position and role of cholesterol in the membrane
186
Describe the structure of a phospholipid
187
Describe the effects of temperature on membrane structure
188
Describe the effects of ethanol on membrane structure
189
Explain why alcohol is used in antiseptic wipes.
190
Define the term diffusion.
191
Define the term facilitated diffusion
192
What is a channel protein?
193
What is a carrier protein?
194
What types of molecules can diffuse directly across the phospholipid bilayer?
195
Describe the movement of water across the phospholipid bilayer
196
State 5 factors that affect the rate of simple diffusion
197
Define the term active transport
198
Describe how carrier proteins are used in active transport
199
Define bulk transport and give two examples
200
Define and describe phagocytosis
201
Define and describe pinocytosis
202
Define and describe exocytosis
203
Describe the role of ATP in bulk transport
204
What is the main difference between active transport and facilitated diffusion?
205
Define the term osmosis
206
What is water potential?
207
What substance has the highest possible water potential of 0 kPa?
208
State the equation that links water potential, solute potential and pressure potential
209
As more solute is added to a solution, what happens to the solute potential and hence the water potential?
210
Describe what would happen to a red blood cell placed in a solution with a more negative water potential than that of its cytoplasm
211
Describe what would happen to a liver cell placed in a solution with a more positive WP than its own cytoplasm
212
Describe what would happen to a root hair cell placed in a solution with lower WP than its own cytoplasm/vacuole
213
Describe what would happen to a guard cell placed in a solution of less negative WP than its own cytoplasm
214
State three events that occur in G1 phase of the cell cycle
215
What happens during the S phase of the cell cycle?
216
What happens during the G2 phase?
217
Describe what may happen in G0 phase of the cell cycle
218
State three cell cycle checkpoints and briefly describe what is being checked for at each
219
State three purpose of mitosis in life cycles
220
Describe the main events of phophase
221
Describe the main events of metaphase
222
Describe the main events of anaphase
223
Describe the main events of telophase
224
Describe how cytokinesis differs between dividing animal cells and plant cells
225
Why would we use the root tip for investigating mitosis?
226
Explain why we warm the root tips in hydrochloric acid when preparing a root tip squash
227
Which stain would we use to stain chromosomes in a root tip squash?
228
What is meiosis?
229
Describe how meiosis produces genetic variation in the gametes produced
230
Describe the difference between anaphase I and anaphase II
231
In which stage of meiosis is the chromosome number halved
232
Explain why genetic variation is important for a population of organisms
233
What is differentiation?
234
Describe and explain how erythrocytes are adapted for their function
235
Explain why a neutrophil contains many lysosomes
236
Describe and explain how sperm cells are adapted for their function
237
Describe how guard cells open in sunny conditions
238
Describe the purpose of cytoskeleton threads and motor proteins in palisade cells
239
Describe how a root hair cell plasma membrane is adapted for transport of mineral ions
240
Describe how cartilage is adapted for its function
241
Define the term tissue
242
State three types of muscle tissue, giving an example of where each is found
243
Give four features of meristematic cells that means they can differentiate easily
244
Describe the differences between multipotent, pluripotent and totipotent stem cells
245
State three characteristics of stem cells
246
State the three main factors that affect the need for an exchange system
247
Explain why smaller organisms have a lower demand for oxygen than larger organisms
248
Describe and explain three features of a good exchange surface
249
Describe how human alveoli are adapted to reduce diffusion distances
250
Describe the role of surfactant in alveoli
251
Describe the mechanism of inspiration
252
Why do alveolar walls contain elastic fibres?
253
Which tissue type comprises alveolar walls?
254
The trachea is lined with ciliated epithelial tissue and goblet cells. Describe the functions of these.
255
The trachea and bronchi are lined with cartilage. Describe why.
256
Describe how the nasal cavity is adapted for exchange
257
Describe the roles of smooth muscle and elastic tissue in the airways
258
Describe precautions that must be taken when using a spirometer
259
Describe what is meant by ‘vital capacity’ and state the factors that it depends upon
260
State the usual range for vital capacity
261
Describe what is meant by ‘inspiratory reserve volume’.
262
Describe what is meant by ‘expiratory reserve volume’.
263
Describe what is meant by ‘residual volume’ and state the standard volume
264
Describe what is meant by ‘tidal volume’ and state a typical figure
265
What is the difference between ‘ventilation rate’ and ‘breathing rate’?
266
State the equation for ventilation rate
267
The normal breathing rate of a healthy 50 year old woman is 18 breaths per minute and her tidal volume is 500 cm3. During strenuous exercise, her ventilation rate increases to 45 000 cm3min-1 and she is breathing 30 times a minute. Calculate her tidal volume during this exercise and state how much higher than normal this figure is.
268
Most bony fish have 5 pairs of gills which are covered by a bony flap, known as the …? What is the function of this bony flap?
269
Describe the structure of gills in bony fish
270
Describe ventilation in bony fish
271
How is air supplied to respiring tisses in an insect?
272
How does air enter the tracheal system in an insect?
273
The ends of tracheoles in insects are filled with tracheal fluid. What is the function of this fluid?
274
When an insect is active, what changes occur in the insect to increase their oxygen supply?
275
Describe three features of an effective transport system
276
Describe three disadvantages of single circulatory systems, as seen in fish
277
Explain why fish do not need as much energy as mammals
278
Describe what is meant by the term open circulation
279
State two disadvantages of open circulatory systems
280
State four advantages of closed circulation over open circulation
281
What is the inner tissue lining of a blood vessel called? What is its role?
282
Describe the three structural layers of an artery
283
What is the role of arterioles?
284
Describe how capillaries are adapted for exchange
285
Describe the function of a venule
286
Describe how veins are adapted to carry blood back to the heart
287
Where is hydrostatic pressure created of the blood created?
288
What is oncotic pressure?
289
What substances might affect the oncotic pressure of the blood?
290
State the cell types that are most likely to be found in blood plasma, tissue fluid and lymph
291
Why can proteins known as plasma proteins not leave the blood plasma?
292
Why can neutrophils enter the tissue fluid but erythrocytes cannot?
293
Describe the role of the lymph fluid
294
How does tissue fluid facilitate exchange of substances to body cells?
295
Describe the simple structure of haemoglobin
296
What is the process known as by which oxyhaemoglobin releases its oxygen to respiring cells?
297
What is the main difference between foetal haemoglobin and adult haemoglobin?
298
Describe three ways in which carbon dioxide is transported
299
Describe the formation of hydrogencarbonate ions
300
Describe how the charge inside a RBC is maintained when hydreogencarbonate ions diffuse into the plasma
301
Describe how the pH inside a RBC is buffered as hydrogen ions build up inside, making the RBC very acidic
302
What is the net result of the Bohr effect?
303
With reference to protein structure, explain how increasing hydrogen ion levels affects haemoglobin.
304
What is the purpose of semilunar valves?
305
Why is the left ventricular wall so much thicker than the right ventricular walls?
306
Why are there so many mitochondria in cardiac muscle?
307
What is the purpose of intercalated discs between adjacent muscle cells?
308
Briefly outline the events of atrial systole
309
Briefly outline the events of ventricular systole
310
Briefly outline the events of diastole
311
What is meant by the term myogenic?
312
What tissue is responsible for initiating the heartbeat?
313
What tissue propagates the electrical signal from the atria to the ventricles, resulting in ventricular systole?
314
Why is there a delay before the AVN depolarises the ventricular walls?
315
Describe the role of the Purkyne tissue
316
What do the letters PQRST indicate in an ECG?
317
What terms describe a slow and a fast heart rate?
318
What happens in atrial fibrillation?
319
What is an ectopic heart beat?
320
Plant transport systems consist of 2 major specialised vascular tissues. Name these, state their transport material and the direction of transport
321
What tissue is found in between the xylem and phloem? What is its function?
322
What is the purpose of parenchyma cells in xylem tissue?
323
What is the purpose of lignin in xylem vessels?
324
How do bordered pits form and what is their purpose?
325
Describe three adaptations of xylem vessels that relate structure to function
326
What two components of phloem tissue are concerned with transport?
327
Why do sieve tube elements contain no nucleus and very little cytoplasm?
328
How are companion cells adapted for active loading?
329
Describe 2 major pathways taken by water to move between cells
330
What allows water to move through cells via the symplast pathway, and by which mechanism of movement?
331
What allows water to move continuously via the apoplast pathway?
332
Why does the presence of starch in the endodermis suggest that an active process is involved?
333
What is the Casparian strip?
334
Explain the significance of the Casparian strip
335
Describe how water is lost via stomata (refer to gradients)
336
Describe the effects of light intensity, humidity and wind speed on the rate of transpiration
337
State two precautions that should be taken to ensure no air bubbles are in the potometer setup
338
The distance moved by the meniscus in a potometer is 45mm in 5 minutes. The radius of the capillary tube is 0.5 mm. Calculate the rate of transpiration.
339
Describe how water moves up the stem via the transpiration pull
340
What property of water causes cohesion?
341
Define the term translocation
342
State two sinks (for translocation) in a plant
343
What is the difference between active loading and active transport?
344
Describe the role of hydrogen ions in active loading
345
Why is sucrose transported in phloem and not glucose?
346
How does sucrose move from the companion cells into the sieve tube elements?
347
Based on what principle does mass flow work in sieve tubes?
348
Based on what principles does phloem unloading work?
349
Describe 3 adaptations of marram grass (xerophyte) and explain their importance
350
Cacti are succulents. What does this mean?
351
Why is it advantageous for some xerophytes to have a low water potential inside their leaf cells?
352
Describe two adaptations of roots that could help a plant survive in arid conditions
353
What is classification?
354
Why do scientists classify organisms?
355
What is taxonomy?
356
What are the eight taxonomic groups in order of largest to smallest?
357
What is the binomial naming system?
358
Why is the binomial naming system important?
359
What are the 5 kingdoms in classification?
360
What are the general features of prokaryotae?
361
What are the general features of protoctista?
362
What are the general features of fungi?
363
What are the general features of plantae?
364
What are the general features of animalia
365
What are the 3 domains of classification?
366
Why are 3 domains preferred to 5 kingdoms?
367
What is the difference between eukarya, bacteria and archaea in terms of ribosomes?
368
What is the difference between eukarya, bacteria and archaea in terms of RNA polymerase?
369
In the new system of classification, what are the 6 kingdoms?
370
Which group has been divided to form eubacteria and archaebacteria?
371
What is the difference between the habitats of archaebacteria and eubacteria?
372
What is phylogeny?
373
What are phylogenetics?
374
What is a phylogenetic tree?
375
What are the advantages of phylogenetic classification over hierarchical / Linnean classification?
376
What is evolution?
377
What did Darwin observe to support his thory of evolution through natural selection?
378
What did Darwin notice about the finches of the Galapagos?
379
What did Darwin determine about the shape of the Galapagos finchs’ beaks and their environment?
380
Who was Alfred Wallace?
381
When Darwin published “On the Origin of Species” describing the theory of evolution through natural selection, why was it originally extremely controversial?
382
What are the 3 main sources of evidence for evolution?
383
What is paleontology?
384
What evidence for evolution is shown in the fossil record?
385
Why is the fossil record not complete?
386
What is comparative anatomy?
387
What is a homologous structure?
388
What do homologous structures provide evidence for?
389
What is divergent evolution?
390
What is comparative biochemistry?
391
How are molecules used in comparative biochemistry?
392
Which molecules can be used in comparative molecular biochemistry?
393
What are the two types of variation between organisms?
394
What is interspecific variation
395
What is intraspecific variation?
396
What are the causes of variation?
397
What are the causes of genetic variation?
398
How do alleles cause genetic variation?
399
How do mutations cause genetic variation?
400
How does meiosis cause genetic variation?
401
How does sexual reproduction (2 partners) cause genetic variation?
402
How does chance cause genetic variation?
403
Why is there much more variation in sexually reproductive organisms than those which reproduce asexually?
404
Are animals or plants more likely to be affected by the environment and cause variation? Why
405
Give an example of a purely environmental variation.
406
In most cases, what causes variation within a population?
407
Give an example of a charachteristic that can be affected by both genetic and environmental factors.
408
It is hard to separate genetic and environmental factors from causing variation. What investigations are done to allow better understanding between nature and nurture?
409
Into which 2 groups can data on characteristic variation be sorted?
410
What is another term for discontinuous variation?
411
What is discontinuous variation?
412
Give an example of discontinuous variation.
413
What causes discrete variation?
414
How is discontinuous variation displayed graphically?
415
What is continuous variation?
416
What is an example of continuous variation?
417
What causes continuous variation?
418
How is continuous variation displayed graphically?
419
Continuous variation typically show what distribution?
420
What is normal distribution?
421
What are the characteristics of normal distribution?
422
What is standard deviation?
423
What does the variation look like if there is a high standard deviation?
424
What does the variation look like if there is a low standard deviation?
425
In normal distribution, what are the typical values for the first 3 standard deviations?
426
What What do the symbols in the standard deviation formula stand for?
427
What is the Student’s t test used for?
428
What is Spearman’s rank correlation coefficient used for?
429
What are the purpose of statistical tests?
430
What is a null hypothesis in a Student’s t test?
431
What is a null hypothesis in a Spearman’s rank?
432
What are the degree of freedom in a Student’s t test?
433
How do you determine significance in a Studen’t t test?
434
What do the probability values in the significance tables mean?
435
How do you determine significance in a Spearman’s rank?
436
What are adaptations?
437
What are the 3 types of adaptation?
438
What is an anatomical adaptation?
439
What is a behavioural adaptation?
440
What is a physiological adaptation?
441
Give an example of an anatomical adaptation.
442
How is Marram grass adapted to stop transpiration?
443
Give an example of a behavioural adaptation.
444
What are the two main types of behavioural adaptation?
445
What is an innate behaviour?
446
What is a learned behaviour
447
Give an example of physiological adaptations.
448
What is convergent evolution?
449
Why does convergent evolution occur?
450
What is natural selection?
451
What are the steps involved in natural selection?
452
What is a selection pressure?
453
What are examples of selection pressures?
454
What are modern examples of evolution?
455
How does anti-biotic resistant bacteria show modern evolution?
456
How do peppered moths show modern evolution?
457
How do sheep blowflies show modern evolution?
458
How do Flavobacterium show modern evolution?
459
What is biodiversity?
460
Why is biodiversity important?
461
Why do humans rely on balanced ecosystems?
462
How can human activities lead to a reduction in biodiversity?
463
What are the 3 ways of measuring biodiversity?
464
Why is it important to measure biodiversity?
465
What is habitat biodiversity?
466
What is species biodiversity?
467
What is species richness?
468
What is species evenness?
469
What is a community?
470
What is genetic biodiversity?
471
Why is genetic variation important?
472
What is sampling?
473
Why is sampling important?
474
What is sampling used for?
475
What are the 2 ways sampling can be carried out?
476
What is random sampling?
477
How is random sampling carried out?
478
What is non-random sampling?
479
What are the 3 main types of non-random sampling?
480
What is opportunistic sampling?
481
What is stratified sampling?
482
What is systematic sampling?
483
What are two techniques that could be used in systematic sampling?
484
What is a line transect?
485
What is a belt transect?
486
What is an interupted belt transect?
487
What is reliability?
488
What can decrease the reliability of the sampling being done?
489
What is sampling bias?
490
What is chance?
491
What are the techniques used in collecting live animal samples?
492
How is a pooter used?
493
How are sweep nets used?
494
How are pitfall traps used?
495
How is tree beating used?
496
How is kick sampling used?
497
How are plants generally sampled?
498
What is a point quadrat and how is it used?
499
What is a frame quadrat?
