Year 10 Paper 2: Organisation and Energy
Covers cell structure and transport, digestion and the circulatory system, pathogens and communicable disease, the body's defence systems and how disease is treated, photosynthesis, and respiration and exercise.
Year 10 here means a typical teaching order, not a syllabus rule. No exam board defines what belongs to Year 10, 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 [2 marks]
Human Defence Systems and Treating Disease
State what an antibiotic is, and state what type of pathogen antibiotics are effective against.
Question 2 [2 marks]
Digestion and the Circulatory System
State the function of the stomach in digestion, and state two things the stomach does to food.
Question 3 [2 marks]
Respiration and Exercise
State the word equation for aerobic respiration in humans, and state one place in a cell where it occurs.
Question 4 [3 marks]
Digestion and the Circulatory System
State the function of bile in digestion, and state which organ produces bile and which organ stores it.
Question 5 [3 marks]
Human Defence Systems and Treating Disease
Describe the difference between how a painkiller and an antibiotic help a patient with a bacterial infection.
Question 6 [3 marks]
Pathogens and Communicable Disease
Chlamydia is a sexually transmitted infection caused by bacteria, which often causes no symptoms.
Describe why this makes chlamydia easily spread, and describe one way its spread can be reduced.
Question 7 [3 marks]
Respiration and Exercise
After vigorous exercise, lactic acid that has built up in the muscles needs to be removed.
State where in the body lactic acid is transported to be broken down, and state what happens to it there.
Question 8 [3 marks]
Photosynthesis
A student tests a variegated leaf (part green, part white) that has been in daylight for several hours, using iodine solution to test for starch.
State the result you would expect in the green part of the leaf and in the white part of the leaf, and explain why.
Question 9 [3 marks]
Cell Structure and Transport
Bacteria are prokaryotic organisms. Animal and plant cells are eukaryotic organisms.
Describe three differences between a prokaryotic cell and a eukaryotic cell.
Question 10 [4 marks]
Pathogens and Communicable Disease
A school recorded the number of pupils absent with a flu-like illness.
On Monday, 18 out of 600 pupils were absent with symptoms. By Friday, 54 out of 600 pupils were absent with symptoms.
Calculate the percentage of pupils absent on each day, then calculate the percentage change in absence over the week.
Question 11 [4 marks]
Respiration and Exercise
At rest, a person takes 16 breaths per minute, and each breath takes in 250 cm^3 of air, of which 4% is absorbed as oxygen into the blood.
Calculate the volume of oxygen absorbed into the blood per minute, in cm^3.
Question 12 [4 marks]
Photosynthesis
A student measures the volume of oxygen gas collected from pondweed using a gas syringe. In 5 minutes, 20 cm^3 of oxygen was collected.
Calculate the mean rate of photosynthesis in cm^3 of oxygen per minute, then calculate how long it would take to collect 50 cm^3 of oxygen at this rate.
Question 13 [4 marks]
Respiration and Exercise
Before exercise, a student's resting heart rate was 68 beats per minute.
Immediately after five minutes of running, their heart rate was 119 beats per minute.
Calculate the percentage increase in the student's heart rate.
Question 14 [5 marks]
Cell Structure and Transport
A red blood cell placed in a beaker of pure water will swell and may burst. A red blood cell placed in a concentrated salt solution will shrink.
Explain, in terms of osmosis, why the red blood cell behaves differently in each solution.
Question 15 [5 marks]
Respiration and Exercise
Yeast is a single-celled fungus that can respire anaerobically in the absence of oxygen, a process used in bread-making and brewing.
Describe the process of anaerobic respiration in yeast, including the word equation, and explain why this process is useful in bread-making.
Question 16 [5 marks]
Digestion and the Circulatory System
Describe how you could test a food sample to find out whether it contains starch, and describe how you could test a different food sample to find out whether it contains a reducing sugar such as glucose.
Question 17 [5 marks]
Cell Structure and Transport
A row of 40 root hair cells absorbs a total of 0.008 mm^3 of water by osmosis in one minute.
Calculate the mean volume of water absorbed by one root hair cell per minute, and calculate how many minutes it would take one root hair cell to absorb 0.0006 mm^3 of water at this rate.
Model solutions
| Question 1[2 marks] | |
|---|---|
| Answer or working | Marks |
| an antibiotic is a medicine/drug that kills bacteria (or prevents their growth) inside the body | B1 |
| antibiotics are effective against bacterial pathogens (not viruses) | B1 |
| Final answer: An antibiotic kills bacteria (or stops them growing) inside the body; antibiotics are effective against bacteria, not viruses | |
| Question 2[2 marks] | |
|---|---|
| Answer or working | Marks |
| the stomach digests protein (using the enzyme protease/pepsin) | B1 |
| the stomach churns/mixes food with digestive juices, and produces hydrochloric acid, which kills bacteria in the food and gives the right pH for protease to work | B1 |
| Final answer: The stomach digests protein (using protease) and churns food with acid, which kills bacteria and gives the right pH for the enzyme to work | |
| Question 3[2 marks] | |
|---|---|
| Answer or working | Marks |
| glucose + oxygen -> carbon dioxide + water | B1 |
| the mitochondria | B1 |
| Final answer: Glucose + oxygen -> carbon dioxide + water; occurs in the mitochondria | |
| Question 4[3 marks] | |
|---|---|
| Answer or working | Marks |
| bile neutralises stomach acid entering the small intestine and emulsifies fats, increasing the surface area for lipase to act | B1 |
| bile is produced by the liver | B1 |
| bile is stored in the gall bladder | B1 |
| Final answer: Bile neutralises stomach acid and emulsifies fats to increase surface area for lipase; it is produced by the liver and stored in the gall bladder | |
| Question 5[3 marks] | |
|---|---|
| Answer or working | Marks |
| a painkiller relieves/treats the symptoms of the infection, such as pain or fever | B1 |
| a painkiller does not kill the pathogen causing the infection, or cure the disease | B1 |
| an antibiotic kills the bacteria causing the infection (or stops them growing), treating the underlying cause of the disease | B1 |
| Final answer: A painkiller relieves symptoms like pain but does not kill the pathogen; an antibiotic kills the bacteria causing the infection, treating the cause | |
| Question 6[3 marks] | |
|---|---|
| Answer or working | Marks |
| many infected people show no symptoms, so do not know they are infected | B1 |
| this means they can pass on the infection to sexual partners without realising, allowing it to spread through the population | B1 |
| a valid prevention method, e.g. using a condom during sexual contact, or being screened/tested regularly | B1 |
| Final answer: Because chlamydia often has no symptoms, infected people can unknowingly pass it on; using a condom or regular screening reduces its spread | |
| Question 7[3 marks] | |
|---|---|
| Answer or working | Marks |
| lactic acid is carried in the blood to the liver | B1 |
| in the liver, lactic acid is converted back into glucose | B1 |
| this conversion requiring oxygen (this is part of the oxygen debt repaid during recovery) | B1 |
| Final answer: Lactic acid is transported in the blood to the liver, where it is converted back into glucose, using oxygen as part of the oxygen debt | |
| Question 8[3 marks] | |
|---|---|
| Answer or working | Marks |
| the green part of the leaf turns blue-black with iodine, showing starch is present | B1 |
| the white part of the leaf stays orange/brown with iodine, showing no starch is present | B1 |
| the white part of the leaf lacking chlorophyll, so it cannot photosynthesise (or produce/store glucose as starch), even in the light | B1 |
| Final answer: The green part turns blue-black (starch present), but the white part stays orange/brown (no starch), because the white part lacks chlorophyll and so cannot photosynthesise | |
| Question 9[3 marks] | |
|---|---|
| Answer or working | Marks |
| prokaryotic cells are much smaller than eukaryotic cells | B1 |
| prokaryotic cells have no nucleus, and their DNA is a single circular strand loose in the cytoplasm rather than in a nucleus | B1 |
| prokaryotic cells may contain one or more small rings of DNA called plasmids, which eukaryotic cells do not have | B1 |
| Final answer: Prokaryotic cells are smaller, have no nucleus (DNA is a loose circular strand), and may contain plasmids; eukaryotic cells have a nucleus and no plasmids | |
| Question 10[4 marks] | |
|---|---|
| Answer or working | Marks |
| Monday percentage = (18/600) x 100 = 3% | M1 |
| Friday percentage = (54/600) x 100 = 9% | M1 |
| percentage change = ((9 - 3)/3) x 100 | M1 |
| a 200% increase | A1 |
| Final answer: Monday 3%, Friday 9%, a 200% increase over the week | |
| Question 11[4 marks] | |
|---|---|
| Answer or working | Marks |
| volume of air per minute = 16 x 250 | M1 |
| 4000 cm^3 | A1 |
| oxygen absorbed = 4% of 4000 | M1 |
| 160 cm^3 | A1 |
| Final answer: 160 cm^3 of oxygen is absorbed into the blood per minute | |
| Question 12[4 marks] | |
|---|---|
| Answer or working | Marks |
| using rate = volume / time | M1 |
| substituting 20 / 5 | M1 |
| 4 cm^3 per minute | A1 |
| time = 50 / 4 = 12.5 minutes | A1independent |
| Final answer: Rate = 4 cm^3 of oxygen per minute; it would take 12.5 minutes to collect 50 cm^3 | |
| Question 13[4 marks] | |
|---|---|
| Answer or working | Marks |
| finding the increase = 119 - 68 = 51 beats per minute | M1 |
| using percentage change = (increase / original) x 100 | M1 |
| substituting (51/68) x 100 | M1 |
| 75% (to 2 significant figures) | A1 |
| Final answer: 75% increase | |
| Question 14[5 marks] | |
|---|---|
| Answer or working | Marks |
| osmosis is the movement of water molecules from a dilute solution to a concentrated solution through a partially permeable membrane | B1 |
| pure water is more dilute (has a higher water concentration) than the cytoplasm inside the cell | B1 |
| water moves into the cell by osmosis down this concentration gradient, causing the cell to swell and potentially burst | B1 |
| the concentrated salt solution has a lower water concentration than the cytoplasm | B1 |
| water moves out of the cell by osmosis, causing it to shrink | B1 |
| Final answer: In pure water, water moves into the cell by osmosis (higher water concentration outside), causing it to swell/burst; in concentrated salt solution, water moves out of the cell by osmosis (lower water concentration outside), causing it to shrink | |
| Question 15[5 marks] | |
|---|---|
| Answer or working | Marks |
| anaerobic respiration in yeast is called fermentation | B1 |
| the word equation: glucose -> ethanol + carbon dioxide | B1 |
| fermentation releasing a smaller amount of energy than aerobic respiration, because the glucose is not fully broken down | B1 |
| the carbon dioxide gas produced becoming trapped in the dough, forming bubbles | B1 |
| this causing the dough/bread to rise before or during baking | B1 |
| Final answer: Yeast ferments glucose anaerobically into ethanol and carbon dioxide (releasing less energy than aerobic respiration); the carbon dioxide produced makes bread dough rise | |
| Question 16[5 marks] | |
|---|---|
| Answer or working | Marks |
| to test for starch, add a few drops of iodine solution to the food sample | B1 |
| a blue-black colour indicates starch is present (it stays orange/brown if absent) | B1 |
| to test for a reducing sugar, add Benedict's solution to a sample and heat it in a water bath | B1 |
| a colour change from blue towards green, yellow, orange or brick-red indicates a reducing sugar is present | B1 |
| the solution remaining blue indicates no reducing sugar is present | B1 |
| Final answer: Starch: add iodine solution, a blue-black colour shows starch is present. Reducing sugar: add Benedict's solution and heat, a colour change from blue to green/orange/brick-red shows a reducing sugar is present | |
| Question 17[5 marks] | |
|---|---|
| Answer or working | Marks |
| using mean volume per cell = total volume / number of cells | M1 |
| substituting 0.008 / 40 | M1 |
| 0.0002 mm^3 per cell per minute | A1 |
| using time = volume required / rate per minute | M1 |
| 0.0006 / 0.0002 = 3 minutes | A1 |
| Final answer: Mean volume absorbed = 0.0002 mm^3 per cell per minute; it would take 3 minutes to absorb 0.0006 mm^3 | |