Download B32008 answers - Glan Afan School

2008 B3: Answers
FOUNDATION TIER
1. (a) (i) vena cava, atrium, ventricle, aorta [4]
(ii) Arrow line continued on left into aorta [1]
(iii) Valve [2]
prevent backflow (of blood)/ blood going the wrong way
(not: stop blood flowing back out of heart)
(b) Muscle; pump; arteries; veins [4]
Question total [11]
2. (a) (i) B [1]
(ii) Urine (not: urea) [1]
(b) (i) Urea [1]
(ii) Protein; glucose (not: sugar) [2]
Question total [5]
3. (a) Phosphate Poor root growth/ too few roots/roots smaller [1]
Nitrate stem shorter/poor stem growth (not: its short) [1]
(b) From water in the soil [1]
Question total [3]
4. (a) (i) Kills (unwanted) microbes/bacteria/ sterilise the wire; [1]
(not: removes microbes/kills germs)
(ii) Keeps microbes away from gel/out/ prevent microbes entering; [1]
(iii) Prevents lid being removed/stop dish being opened [1]
(not: keeping microbes out)
(b) Plotting correct (+/- 0.5 square) -1 per error; [2]
Line drawn with ruler joining centre of plots [1]
(c) (i) Correct graph reading/138 (not: if oC); [1]
(ii) Grow faster at 25ºC than at 15ºC [1]
(iii) Slows/prevents growth / multiplication of bacteria [1]
(not: kills bacteria/less bacteria
Question total [9]
5. (a) Contains living bacteria [1]
(b) Kills/destroys microbes/sterilise [1]
(not: remove/denature/pasteurise)
(c) (i) 30ºC [1]
(ii) 43ºC [1]
(no double penalty for units)
(d) 8 – 10 hours [1]
(e) (i) Bacteria [1]
(ii) Proteins solidify/sets yogurt/milk [1]
(not: acids act on protein)
Question total [7]
FOUNDATION AND HIGHER TIER
6/1. (a) (i) Tube A 1.9 (allow: between 1.8 to 2.0) [1]
Tube B 3.6 [1]
(ii) Shoot in tube B has more / larger leaves / larger surface area [1]
(not: reference to cuticle/stomata numbers)
Loses more water/mass by [1]
transpiration / transpires more [1]
(not: evaporation)
[ORA]
(iii) Prevent evaporation (not: transpiration/water loss)) [1]
(iv) Air directed at the leaves by a fan [1]
(b) Stoma(ta)/guard cells [1]
Question total [8]
7/2. (a) outer membrane completed [1]
( allow if pseudopodia drawn touching)
bacteria in vacuole [1]
(b) blood clot is formed/scab/ platelets seal wound [1]
(not: platelets unqualified)
(intact) skin/prevents entry of bacteria [1]
Question total [4]
8/3. (a) (i) glucose / sugar / amino acids / mineral salt / named salt/minerals [1]
(ii) to provide oxygen for respiration / mixing [1]
(not: stirring/reference to fermentation)
(b) fungi / moulds [1]
Question total [3]
HIGHER TIER
4. (a) (i) 55 (ºC) [1]
(ii) enzymes are denatured/destroyed (not: killed) [1]
(iii) substrate / pulped apple used up / all juice extracted/ all pectin broken
down/maximum working of pectinase [1]
( not: reference to limiting factor unqualified)
(iv) pH / volume / concentration of enzyme/variety or type of apple [1]
(not: amount/quantity/temperature)
(b) pre-digestion of baby foods / biological washing powders/cheese making/soft
centred chocolates/lactose free milk (not: beer making) [1]
Question total [5]
5. to lungs/alveoli [1]
*pulmonary vein [1]
*left atrium [1]
*left ventricle [1]
correct reference to (functioning of ) valve (preventing backflow) [1]
(* mark for 2 structures in correct link)
6. (a) A Bowmans capsule [1]
B collecting duct [1]
(b) On capillary knot [1]
(c) protein � x x [1]
water � � � [1]
urea � � � [1]
glucose � � x [1]
(d) (i) (I) 80
(II) 6 [2 × 1]
(ii) More people are able to work (full time) /ORA [1]
(iii) Relatives will have similar tissue types /
genes /DNA/ less chance of rejection [1]
(not: similar blood groups)
Question total [11]
7. (a) Made the bacteria resistant (to the antibiotic) / caused mutation [1]
(b) As a control / fair test / to show the antibiotic was needed to kill bacteria [1]
(c) Bacteria mutate (not: change unqualified by genes) [1]
Mutations cause resistance [1]
Resistance is passed on via genes/reproduction [1]
(not: bacteria become resistant)
[Any 3 × 1]
Question total [5]
8. (a) (i) Mitosis / cloning/cell division [1]
(not: reproduction/division/meiosis)
(ii) Antigen [1]
(iii) Antibody [1]
(iv) Memory cell (not: wbc/leucocyte) [1]
Triggers/causes a rapid/immediate response when the virus infects
again [1]
(b) (i) (I) 120 [1]
(II) 160 [1]
(ii) There is no link / ending MMR vaccinations does not halt rise in
autism [1]
(c) Vaccination prevents disease spreading/reduces number of cases of
measles/evidence shows MMR doesn’t cause autism. [1]
Question total [9]