Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

68 Cards in this Set

  • Front
  • Back
Some metabolic reactions become less efficientin cold weather so the organism generates moreheat to keep warm


Sheep learn to ignore sounds that have noimportance to them


The ears of African elephants are larger thanthose of Asian elephants, due to differences inthe environment


Formation of a sun tan when human skin isexposed to sunlight


Suggest how you could investigate the antimicrobial properties of pine needles.
1. Filter paper is soaked in extract and pine needles is placed on agar plate.

2. with bacterial

3. Using aseptic conditions, appropriate sealing methods.

4. Left in incubation for 24 hours.

5. Incubate at a temp of 25 c

6. (looking for) {clear area / inhibition zone /loss of cloudiness /reduced cell number/ eq}(around pine needles, extract / filter paper /wells)

7. (clear area ) shows no bacteria

8. Suitable control

Name the bond that is broken to convert starch into its monosaccharidebuilding blocks.


Name the monosaccharide formed when the bonds in starch are broken.

Alpha glucose

Suggest why bioplastic is described as a more sustainable form of packagingthan oil-based plastics.

1. Bioplastic comes from plants.

2. Plants are renewable.

3. Oil-based plastic is from a non-renewable source.

Bioplastic is biodegradable. Suggest one environmental advantage of usingbiodegradable packaging.

1. Will not contribute to landfill.

2. Can be decomposed.

Suggest why a drug can be tested on rats before testing on humans.

1. No harm to human.

2. Rats have similar metabolic rate.

3. Ethical issues.

4. Looking for toxicity effect.

State what is done during each of the following phases of testing on humans.

Phase 1

Idea of drug tested on {a small number /healthy} individuals

2. ref to low concentration / monitor safety

Phase 2

1. idea that drug tested on small number ofpatients

2. monitor effectiveness of treatment

Describe and explain how this tissue is adapted for the transport of water andsupport in a plant.

Water transport:

1. hollow tubes / no living contents / end wallsbroken down 2. idea of allow movement of water e.g.columns of water / vertical movement

3. Waterproof material 4. idea that keeps water in the vessel e.g. lesswater lost

5. (pores / eq} 6. to allow sideways movement of water


1. Ligin for strength

2. Rings/spirals for strength ad flexibility.

Suggest two reasons why the seeds need to be dried and then stored in coldconditions.

1. Inhibits germination.

2. Slows down biochemical reactions.

3. Prolongs seed survival.

4. Drying reduces freezing effect.

Suggest why seed germination is tested at regular intervals.
1. idea that checking {seed viability /germination success

2. allows new seeds to be produced

3. idea that stored seeds may need replacinge.g. due to decay / death

Give two ways in which zoos help to conserve endangered species.

1. maintaining the endangered species from poachers/ predation

2. (captive) breeding programmes

3. reintroduction into the wild

4. scientific research / example given /

5. education / example given

Suggest the form in which the nitrogen was supplied in the watering solution.


Explain why clear zones are found

The substance diffused out

Killed the bacteria.

Explain the function of a disc with nothing

To act as a control

Suggest how you would calculatethe mean diameter of this clear zone.

1. Record several measurements

2. Divide by number of measurements to obtain a mean.

Suggest one reason why it was good safety practice to incubate the Petri dish at25°C rather than at 37°C.
1. 37°C is (human) body temperature

2. (this temp) allows growth of {pathogenic /eq} bacteria / encourages more rapid {growth/reproduction

Give the name of one of the other two domains.
Bacteria / Eubacteria / Archaebacteria / Archaea
Describe the structure of a plant cell wall.

1. Cellulose

2. As microfibrils.

3. Held together by hydrogen bonds.


Site where there was no cell wall and thecytoplasm linked the two adjacent cells


Dark line that is the boundary between one celland the next cell

Middle Lamella

Starch is a polymer of one monosaccharide.Name this monosaccharide.

Alpha glucose

Describe two ways in which the structure of starch is related to its function.
1. Made up of many glucose monomers.

2. Energy storage / glucoseis the respiratory substrate

3. Large

4. Insoluble.

5. Compact

6. Can be stored.

7. Branches

8. Increased mobilisation

What do low alleles mean?

1. Low genetic diversity.

2. Selective advantage/ lack of adaptation.

3. Less likely to survive.

4. More risk at extinction.

A female cheetah often mates with several different males and gives birth totwo or three cubs at a time, each having a different father. Suggest why this may be advantageous to cheetahs.
1. {greater / eq} genetic diversity (amongst thelitter) /

2. greater chance that will {survive / eq}

3. increased chance of fertilisation / pregnancy/ 4. increase in population size

Suggest what effect transferring Rafa from one zoo to another had on geneticdiversity in this species.
1. increases genetic diversity

2. (because it) allows {outbreeding / mating /eq} with (genetically) different individuals /eq ;3. stop/reduces {inbreeding / mating withparents / siblings}

4. (which) reduces genetic diversity

Describe an experiment to find the optimum nitrate ion concentration for thegrowth of wheat seedling roots.

1. 3+ sensible nitrate concentrations.]

2. Repeat each concentration.

3. All seedlings, same age, same plant.

4. Solution used should contain other mineral ions.

5. Temperature, light, volume of mineral solution variable kept constant.

6. Measure growth of root to measure otimum rate of nitrate ion concentration.

Give one similarity and two differences, other than the use of a placebo, betweenthese two protocols.


Extracting drug from plant/try to find a suitable dose/ used patients

Difference 1:

Idea that only contemporary testing will useanimals

2. idea that only contemporary testing will {test onhealthy people / have phase 1}

3. idea that only contemporary testing will payvolunteers

4. idea that only contemporary testing may involvedouble-blind trials

5. idea that only contemporary testing will {usestatistical analysis / reference to phase 3 / uselarge number }

6. idea of more regulation

7. idea of controlling {factors /variables / eq} intested cohort e.g. age, lifestyle

Suggest two reasons why it is better to store seeds rather than to store wholeplants.
1. take {less / smaller} space

2. can have more individuals

3. reference to {greater / more} genetic variety ;4. idea of less {maintenance / cost}

5. likely to survive longer

6. can freeze seeds

Suggest why it is better to store seeds from several individual plants of onespecies rather than seeds from one individual plant.

1. Less chance of inbreeding.

2. Maintain genetic diversity.

3. Reduce chance of storing seeds with disease.

Suggest how seeds from these Encholirium species may need to be treated toensure their long term survival in a seedbank.

1. Drying

2. Sterilisation

3. Low oxygen

4. Absence of light.

5. Low temp

Compare the structure of a cellulose molecule with the structure of starch.

1. Both made up of glucose.

2. Both have glycosidic bonds

3. Starch is a glucose Cellulose is b glucose.

4. Starch (Amylose + Amylopectin)

5. All monomers are the same orientation in starch. Inverted in cellulose.

6. Straight chain in cellulose. Branched in starch.

Explain how the arrangement of cellulose microfibrils contributes to thephysical properties of plant fibres.

1.Strength, flexibility

2. Hydrogen bonding/several layers/criss cross links of microfibrils.

Give two functions of xylem vessels

1. Transport water.

2. Support/stability.

3. Transport of minerals

Suggest three factors that would need to be kept constant in thisinvestigation (Tensile strength)
1. length (of fibre)

2. diameter (of fibre)

3. temperature

4. fibre came from the same source

5. stored for the same length of time

6. same way of applying the {masses / knots /

7. same humidity

8. water content of fibre / level of drying

Describe how the results obtained would be processed to produce a mean.

Add sets all together and divide by number of sets.

Suggest why a smaller mass would increase accuracy.

Smaller percentage error

Suggest why the use of oil-based plastic fibres such as nylon, rather thanplant fibres, does not contribute to sustainability.
1. oil is a {non-renewable / finite (resource)

2. (plant fibres) can be regrown / replanted / eq(so is sustainable)

3. ref to time scale

Describe how zoos use these programmes to help conserve rare species

1. to increase numbers/population size

2. to {maintain / increase} genetic diversity/reduce genetic drift /

3. protect from {predators / poachers

Captive Breeding:

1. Selection of mates/records kept (stud books)

2. Inter zoo animal movement


1. Raise awareness through education of local population.

2. Select habitat

All the seedlings were grown from seeds from the samewheat plant. Suggest why this would improve the validity of the results.

Seeds are the same age and are under the same conditions.

Reduced effect of genotype.

Suggest two factors, other than the time for growth and the source of theseeds, that should have been kept constant in this investigation.
1. volume of solution

2. light

3. temperature

4. concentration of other mineral ions

5. pH

6. initial status of seedlings e.g. height

Describe how the bacteria should be added to the Petri dish.

1. Aseptic technique, use sterile equipment.

2. Spread bacteria law, spread over agar.

Explain why the lid was secured in this way

1. Reduces contamination of culture.

2. Allows entry of oxygen eg. aerobic conditions.

3. Reduces growth of harmful bacteria.

Suggest why an incubation temperature of 37°C should not be used in aschool or college laboratory.

Encourages growth of bacteria that are harmful to humans.

Describe and explain why asexual reproduction results in low genetic diversity.

1. Less alleles in the gene pool.

2. Asexual reproduction leads to offspring being genetically identical.

3. No recombination of genetic material (no meiosis)

4. Variation is only possible by mutation.

The effect of varying nitrate ion concentration on the growth of one plant speciescan be investigated in a laboratory. Describe how this investigation can be carried out to produce reliable results

1. 5 different nitrate concentrations.

2. Repeat of each concentration.

3. Measure increase in mass/length/height

4. Use plants that are the same age

5. A biotic factors (Temp, light, water, pH, CO2 concn)

6. Control variable (no nitrate)

Explain why his paper was checked by scientists at this stage.

Peer review / conclusions drawn from data are { logical /valid / eq } / data are {acceptable / reliable} / check forplagiarism ;
Suggest two ways, other than publication in a journal, that scientists can useto present their data to the scientific community.
1. (scientific) conference/ poster / presentation/ seminar/ lecture

2. internet / eq, e.g. websites – blogs

3. book / scientific magazine

Explain what is meant by the phrase ‘allowed critical evaluation of his data bythe scientific community’ in stage 3.
idea of {checking his methods / repeating experiments/ eq} ;2. to collect more data /review his data / test his results/ eq ;3. to see if his results could be replicated / checkreliability of data
Explain why it may be better to make packaging from starch rather than fromoil-based products.
1. plants can be {re-grown / sustainable / eq} OR starch {renewable / sustainable} oil is { non- sustainable / non-renewable eq}

2. idea of biodegradability ;3. idea of cheapness

Suggest why the discs should be sterilised before being soaked in the extract

1. So there is no bacteria on them.

2. That could be harmful.

3. Or that could compete with other bacteria.

Describe what the seedbank will do with these seeds to ensure the long-termconservation of the species.

1. Clean seeds.

2. Dry seeds.

3. Store at low temperatures.

4. idea of regularly testing viability (during storage ofseed)

5. idea of what to do if viability decreases, e.g. if lessthan 75% germinate collect fresh seed for storage

Suggest advantages of selecting seeds of different sizes for long-term storage.
1. idea of maintaining or increasing {genetic diversity/ size of gene pool / genetic variation} 2. idea of more chance of having beneficial alleles

3. increases chance of future survival {ifenvironment changes / due to higheradaptability

4. less chance of all being susceptible to a disease

Explain why placebos are used to test the efficiency of new drug treatments.
1. inactive substance / no drug /

2. idea that it is used as a control e.g.comparison with the actual drug

3. idea of psychological effect of takingeither a drug or a placebo

Suggest how you would use this apparatus to enable a valid comparison of thetensile strength of fibres from two different plants.

1. Control variables: length/age/source

2. Environmental variable: Temperature, humidity.

3. Size of masses used

4. Add masses until fibre breaks.

5. Repeat and find the mean.

6. Take out anomalous result.

7. Safety procedure.

Name the three domains.




Explain how organisms can be classified into taxonomic groups.

1. Organisms with shared/common characteristics

2. , similarities in DNA,molecular phylogeny, similaries in behaviour.

Suggest how Woese’s idea was critically evaluated.

1. Peer reviewed.

2. Published in scientific journal.

3. Presented at a scientific conference.

4. Other scientists repeat experiments to test reliability.

Suggest how this captive breeding programme in the six zoos ensures thatgenetic diversity is maintained in this species.

1. Prevent inbreeding.

2. Select mates.

3. Captive inbreeding will increase population.

4. Studbooks: records of breeding programme.

5. Avoiding genetic drift.

6. Measuring genetic diversity.

7. Exchange animals for breeding.

Suggest three factors that could affect the survival chances of black-footedferrets when they are reintroduced to the sites shown on the map.

1. Loss of habitat

2. Availability of prey

3. Competition with other species.

4. Predators

5. Disease

Describe and explain the procedures that must be followed before these drugscan be tested on patients.
1. idea of testing on non-humans e.g. animals,tissue culture ;2. to test for toxicity / eq ;3. idea of testing on healthy volunteers ;4. to test for side effects
Explain how a double blind trial is used to test a new drug.
1. Idea of tested on two groups ofpatients (with the condition) ;2. reference to use of placebo ;3. (placebo) used as a {control /comparison} with the actual drug ;4. reference to psychological effect ofplacebo / eq ;5. idea that neither testers nor patientsknow if the treatment contains thedrug or not ;6. idea that this removes bias ;7. idea of testing to find out if drug iseffective
Describe how you could use the equipment in this experiment to compare thetensile strength of nettle fibres with that of nylon fibres.
1. named fibre variable controlled e.g.length, width, mass ;2. environmental variable controlled, e.g.temperature, humidity ;3. named procedural variable controlled, e.g.size of masses used ;4. idea of adding masses until fibre breaks /eq ;5. repeat and find the { mean / average } ;6. reference to action taken in case of{ anomalous result / outlier } ;7. reference to safety procedure
Woese suggested that organisms could be placed in taxonomic groups based onmolecular phylogeny. Explain what is meant by this statement.
idea that organisms with { specific /particular / shared / common / similar/ eq } { characteristics / features /traits / eq } are placed in a group ;2. idea that taxonomic groups havespecific differences ;3. idea that phylogeny describes{evolutionary / genetic} relationship ;4. idea that molecular phylogeny basedon similarities in { DNA / DNAsequence / proteins