Year 11 Paper 5: Biology Focus
Covers cell biology, organisation, infection and response, bioenergetics, atomic structure and bonding.
Year 11 here means a typical teaching order, not a syllabus rule. No exam board defines what belongs to Year 11, and schools sequence the course differently. Check it against your own scheme of work before using it to decide what a class has covered.
Questions
Question 1 [4 marks]
Atomic Structure and the Periodic Table
An ion of oxygen, O2-, has a mass number of 16 and an atomic number of 8.
State the number of protons, neutrons and electrons in this ion of oxygen.
Question 2 [5 marks]
Cell Biology
A student investigates the effect of hydrogen peroxide concentration on the rate of the reaction catalysed by catalase in celery extract, measuring the volume of oxygen gas produced in 60 seconds.
Using 1% hydrogen peroxide, 18 cm^3 of oxygen gas is collected in 60 seconds. Using 3% hydrogen peroxide, 54 cm^3 of oxygen gas is collected in 60 seconds.
Calculate the percentage increase in the rate of reaction caused by using the higher concentration of hydrogen peroxide.
Question 3 [5 marks]
Organisation
A sample of blood has a total volume of 5.0 cm^3.
The sample contains 2.2 cm^3 of red blood cells, white blood cells and platelets, and the rest of the sample is plasma.
Calculate the percentage of the blood sample's volume that is plasma.
Question 4 [5 marks]
Infection and Response
In an antibiotic sensitivity test, a bacterial lawn is grown on agar with an antibiotic disc placed on the surface.
The clear zone (zone of inhibition) around the disc is a circle of diameter 18 mm.
Calculate the area of the zone of inhibition. Give your answer to 3 significant figures.
State what a larger zone of inhibition indicates about the antibiotic.
Question 5 [5 marks]
Cell Biology
A student places identical potato chips into salt solutions of different concentrations to investigate osmosis.
One potato chip has a mass of 5.20 g before the experiment. After 24 hours in a 0.4 mol/dm^3 salt solution, the potato chip has a mass of 4.68 g.
Calculate the percentage change in mass of the potato chip, and state whether this is an increase or a decrease. Give your answer to 1 decimal place.
Question 6 [6 marks]
Bonding, Structure and the Properties of Matter
A sample of a nanoparticle catalyst has a total volume of 6.0 x 10^-6 cm^3.
Each spherical nanoparticle in the sample has a volume of 4.0 x 10^-19 cm^3.
Calculate the number of nanoparticles in the sample, giving your answer in standard form.
Question 7 [6 marks]
Bioenergetics
During vigorous exercise, muscle cells need to respire faster to release more energy.
Explain, in terms of the processes taking place in cells, why an athlete's breathing rate and heart rate increase during vigorous exercise.
Question 8 [6 marks]
Organisation
Cardiac output is the volume of blood pumped by the heart in one minute.
A patient has a cardiac output of 4.8 dm^3 per minute and a heart rate of 80 beats per minute.
Calculate the patient's stroke volume, in cm^3. Use cardiac output = heart rate x stroke volume.
Question 9 [6 marks]
Atomic Structure and the Periodic Table
An ion of an element has the electronic structure 2,8 and an overall charge of 2+.
Deduce the atomic number of this element, state its identity, and state the group of the periodic table it belongs to.
Question 10 [6 marks]
Organisation
The heart has four chambers: the left atrium, right atrium, left ventricle and right ventricle.
Explain why the wall of the left ventricle is thicker and more muscular than the wall of the right ventricle.
Question 11 [6 marks]
Bioenergetics
A green plant carries out both photosynthesis and respiration continuously.
Explain how the plant's net exchange of gases with the atmosphere differs between a bright day and at night.
Model solutions
| Question 1[4 marks] | |
|---|---|
| Answer or working | Marks |
| protons = atomic number = 8 | M1 |
| neutrons = mass number - atomic number, 16 - 8 | M1 |
| 8 neutrons | A1 |
| electrons = 10, since a 2- ion has 2 more electrons than protons | B1 |
| Final answer: 8 protons, 8 neutrons, 10 electrons | |
| Question 2[5 marks] | |
|---|---|
| Answer or working | Marks |
| finding the rate with 1% hydrogen peroxide, 18 / 60 = 0.3 cm^3 per second | M1 |
| finding the rate with 3% hydrogen peroxide, 54 / 60 = 0.9 cm^3 per second | M1 |
| finding the increase in rate, 0.9 - 0.3 = 0.6 cm^3 per second | M1 |
| (0.6 / 0.3) x 100 | M1 |
| 200% | A1 |
| Final answer: 200% increase in the rate of reaction | |
| Question 3[5 marks] | |
|---|---|
| Answer or working | Marks |
| plasma volume = 5.0 - 2.2 | M1 |
| 2.8 cm^3 | A1 |
| using percentage = (plasma volume / total volume) | M1 |
| substituting (2.8 / 5.0) x 100 | M1 |
| 56% | A1 |
| Final answer: 56% of the blood sample's volume is plasma | |
| Question 4[5 marks] | |
|---|---|
| Answer or working | Marks |
| radius = diameter / 2 = 9 mm | M1 |
| using area = pi r^2 | M1 |
| correct evaluation before rounding | M1 |
| 254 mm^2 (3 sf) | A1 |
| stating a larger zone of inhibition indicates the antibiotic is more effective | B1 |
| Final answer: 254 mm^2 (3 sf); a larger zone indicates the antibiotic is more effective | |
| Question 5[5 marks] | |
|---|---|
| Answer or working | Marks |
| finding the change in mass, 4.68 - 5.20 = -0.52 g | M1 |
| dividing the change in mass by the original mass | M1 |
| multiplying by 100 | M1 |
| -10.0% | A1 |
| stating this is a decrease (loss of mass) | B1 |
| Final answer: -10.0% (a decrease in mass) | |
| Question 6[6 marks] | |
|---|---|
| Answer or working | Marks |
| using number of nanoparticles = total volume / volume of one nanoparticle | M1 |
| substituting (6.0 x 10^-6) / (4.0 x 10^-19) | M1 |
| correctly combining the powers of ten, -6 - (-19) = 13 | M1 |
| 1.5 x 10^13 | A1 |
| stating individual nanoparticles are typically between 1 and 100 nm in size, much smaller than particles in a bulk sample of the material | B1 |
| explaining this huge number of tiny particles per gram is what gives nanoparticle materials their very large total surface area | B1 |
| Final answer: 1.5 x 10^13 nanoparticles; this huge number of tiny particles per gram gives nanoparticle materials their very large total surface area | |
| Question 7[6 marks] | |
|---|---|
| Answer or working | Marks |
| muscle cells respiring more to release more energy for contraction | B1 |
| increased respiration requiring more oxygen and producing more carbon dioxide | B1 |
| breathing rate and depth increasing to take in more oxygen and remove more carbon dioxide | B1 |
| heart rate increasing to pump blood faster around the body | B1 |
| this increasing the rate of delivery of oxygen and glucose to the muscle cells | B1 |
| this increasing the rate of removal of carbon dioxide (and lactic acid) from the muscles | B1 |
| Final answer: Breathing and heart rate increase to supply more oxygen and glucose and remove carbon dioxide faster, for increased respiration | |
| Question 8[6 marks] | |
|---|---|
| Answer or working | Marks |
| converting cardiac output to cm^3, 4.8 x 1000 | M1 |
| 4800 cm^3 per minute | A1 |
| rearranging to stroke volume = cardiac output / heart rate | M1 |
| substituting 4800 / 80 | M1 |
| 60 cm^3 | A1 |
| stating the unit as cm^3 (per beat) | B1 |
| Final answer: 60 cm^3 stroke volume | |
| Question 9[6 marks] | |
|---|---|
| Answer or working | Marks |
| finding the number of electrons in the ion, 2 + 8 = 10 | M1 |
| recognising a 2+ ion has 2 fewer electrons than protons | M1 |
| atomic number = 10 + 2 | M1 |
| atomic number 12 | A1 |
| identifying the element as magnesium | B1 |
| stating the element is in Group 2 (it loses its 2 outer electrons to form a stable ion) | B1 |
| Final answer: Atomic number 12; magnesium; Group 2 | |
| Question 10[6 marks] | |
|---|---|
| Answer or working | Marks |
| the left ventricle pumping blood around the whole body (the systemic circulation) | B1 |
| the right ventricle only pumping blood to the lungs (the pulmonary circulation), a much shorter distance | B1 |
| blood needing to be pumped at a higher pressure to reach the whole body than to reach only the lungs | B1 |
| the left ventricle therefore needing to contract with more force than the right ventricle | B1 |
| a thicker, more muscular wall allowing the left ventricle to contract with greater force | B1 |
| this generating the higher pressure needed to pump blood all the way around the body | B1 |
| Final answer: The left ventricle pumps blood around the whole body, much further than the right ventricle pumps to the lungs, so it needs a thicker wall to generate higher pressure | |
| Question 11[6 marks] | |
|---|---|
| Answer or working | Marks |
| respiration taking place continuously in the plant, day and night, using oxygen and producing carbon dioxide | B1 |
| photosynthesis only taking place in daylight, using carbon dioxide and producing oxygen | B1 |
| the rate of photosynthesis being greater than the rate of respiration on a bright day | B1 |
| stating that overall, the plant takes in carbon dioxide and releases oxygen as a net exchange during the day | B1 |
| no photosynthesis occurring at night, so respiration is the only gas exchange process taking place | B1 |
| stating that overall, the plant releases carbon dioxide and takes in oxygen as a net exchange at night | B1 |
| Final answer: By day, photosynthesis exceeds respiration so the plant is a net absorber of CO2 and releaser of oxygen; at night, with no photosynthesis, respiration alone makes it a net releaser of CO2 | |