Science: Full Practice Paper 4 Worksheet with Answers

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CE.S-T4 Science: Full Practice Paper 4

ISEB COMMON ENTRANCE CE.S-T4 · Calculator allowed · about 60 minutes

Total Marks

Name: _______________________________ Date: ____ / ____ / ______

Answer ALL questions. Show all your working.

1

Which gas is needed by human body cells to release energy from glucose during respiration?

A) Carbon dioxide
B) Oxygen
C) Nitrogen
D) Hydrogen

(Total for Question 1 is 1 mark)

2

Which of these animals is a vertebrate?

A) Spider
B) Earthworm
C) Salmon
D) Snail

(Total for Question 2 is 1 mark)

3

Leah is investigating whether the number of hours of sleep pupils get affects their reaction time the next day. She asks ten pupils how many hours they slept the previous night, then measures each pupil's reaction time using a ruler-drop test.

(a)State the independent variable in Leah's investigation.(1)

(b)State the dependent variable in Leah's investigation.(1)

(Total for Question 3 is 2 marks)

4

Complete the two missing words in these sentences about microorganisms that cause disease.

(a)A pathogen that can only reproduce inside a living host cell, and cannot survive independently, such as the one that causes flu, is called a ______.(1)

(b)A pathogen that is a single-celled living organism with its own cell wall, cytoplasm and genetic material, such as MRSA, is called a ______.(1)

(Total for Question 4 is 2 marks)

5

Describe the job of each of these three parts of a plant involved in transporting water and nutrients: the roots, the xylem, and the phloem.

(Total for Question 5 is 3 marks)

6

Explain why individuals of the same species, such as pupils in a class, often show variation in characteristics such as height. Give one genetic cause and one environmental cause of this variation.

(Total for Question 6 is 3 marks)

7

A reflex action, such as pulling a hand away from something hot, happens automatically and very quickly. Describe the job of each of these four parts of the pathway (the reflex arc): the receptor, the sensory neurone, the relay neurone (in the spinal cord), and the motor neurone.

(Total for Question 7 is 4 marks)

8

Freya investigates how storage temperature affects the growth of mould on bread. She takes identical pieces of bread, sprays each with the same small amount of water, seals each in an identical bag, and stores them at four different temperatures for one week. She then estimates the percentage of each sample's surface covered in visible mould.

Storage temperature (degC): 4	20	30	37
Surface covered in mould (%): 2	35	58	20

(a)Identify the independent variable in Freya's investigation.(1)

(b)State one variable Freya kept the same to make this a fair test.(1)

(c)Describe the relationship between storage temperature and mould growth shown by the results, for temperatures between 4 degC and 30 degC.(1)

(d)Suggest why storing bread in a fridge (at about 4 degC) helps to keep it fresh for longer, referring to the results.(1)

(Total for Question 8 is 4 marks)

9

A food chain in a UK woodland is: oak leaves -> caterpillar -> blue tit -> sparrowhawk.

(a)Identify the primary consumer in this food chain.(1)

(b)Name the trophic level of the sparrowhawk in this food chain.(1)

(c)Give one reason why not all of the energy in the caterpillar's body is transferred to the blue tit that eats it.(1)

(d)The caterpillars in this woodland contain a total of 5000 kJ of energy. Only 10% of this energy is transferred to the blue tits that eat them. Calculate the energy available to the blue tits.(1)

(Total for Question 9 is 4 marks)

10

A hazel flower is pollinated by wind, while a foxglove flower is pollinated by insects.

(a)State two features of a wind-pollinated flower, such as hazel.(2)

(b)State two features of an insect-pollinated flower, such as foxglove.(2)

(Total for Question 10 is 4 marks)

11

Which change of state describes a liquid turning into a gas at any temperature, not just at its boiling point?

A) Boiling
B) Evaporation
C) Condensation
D) Sublimation

(Total for Question 11 is 1 mark)

12

Which of these substances is a compound?

A) Oxygen gas
B) Water
C) Iron
D) Gold

(Total for Question 12 is 1 mark)

13

Daniel investigates whether the type of metal (magnesium, zinc or copper) affects how quickly it reacts with the same dilute hydrochloric acid, judging the rate by timing how long it takes for bubbling to stop.

(a)State the independent variable in Daniel's investigation.(1)

(b)State the dependent variable in Daniel's investigation.(1)

(Total for Question 13 is 2 marks)

14

Complete the two missing words in these sentences about acids and reaction rates.

(a)A solution with a pH greater than 7 is described as ______.(1)

(b)A substance that speeds up a chemical reaction without being used up itself is called a ______.(1)

(Total for Question 14 is 2 marks)

15

When magnesium reacts with dilute hydrochloric acid, a gas is produced. Name this gas, describe a test (including the positive result) that would confirm its identity, and state the two types of products formed whenever a metal reacts with an acid.

(Total for Question 15 is 3 marks)

16

Marble is a metamorphic rock formed from limestone, a sedimentary rock. Explain how this happens, referring to heat, pressure and melting.

(Total for Question 16 is 3 marks)

17

Amara investigated the rate of reaction between marble chips (calcium carbonate) and dilute hydrochloric acid. In each experiment she reacted the same volume of acid with an excess of marble chips, and measured the total volume of gas produced every 30 seconds. She repeated the experiment using acid at two different concentrations.

Time (s): 0	30	60	90	120	150
Volume of gas with 1 mol/dm³ acid (cm³): 0	12	22	29	33	33
Volume of gas with 2 mol/dm³ acid (cm³): 0	20	32	36	36	36

(a)Identify the independent variable in Amara's investigation.(1)

(b)Name the gas produced in this reaction.(1)

(c)State how the graph of these results would show that the reaction with 2 mol/dm³ acid has finished.(1)

(d)Explain, using ideas about particle collisions, why the reaction with 2 mol/dm³ acid produces gas faster than the reaction with 1 mol/dm³ acid.(1)

(Total for Question 17 is 4 marks)

18

Dry air is approximately 78% nitrogen, 21% oxygen, with small amounts of other gases including carbon dioxide.

(a)Calculate the percentage of dry air made up of gases other than nitrogen and oxygen.(1)

(b)State one human activity that increases the amount of carbon dioxide in the atmosphere.(1)

(c)Name one process, carried out by plants, that removes carbon dioxide from the atmosphere.(1)

(d)Explain why increasing carbon dioxide in the atmosphere is linked to the Earth warming up.(1)

(Total for Question 18 is 4 marks)

19

Magnesium burns in oxygen to form magnesium oxide. A student burns 4.8 g of magnesium completely in oxygen and obtains 8.0 g of magnesium oxide.

(a)Write a word equation for this reaction.(1)

(b)Write the balanced symbol equation for this reaction, including state symbols.(1)

(c)Calculate the mass of oxygen that reacted with the magnesium, using the law of conservation of mass.(1)

(d)Explain, in terms of atoms, why the law of conservation of mass applies to this reaction.(1)

(Total for Question 19 is 4 marks)

20

Classify each of the following, giving a reason for each: oxygen gas (O2), carbon dioxide (CO2), and air.

(a)State whether oxygen gas (O2) is an element or a compound, and explain your answer.(1)

(b)State whether carbon dioxide (CO2) is an element or a compound, and explain your answer.(1)

(c)State whether air is an element, a compound or a mixture, and explain your answer.(1)

(d)Explain one way that the gases in air could be separated back into their individual substances.(1)

(Total for Question 20 is 4 marks)

21

Which quantity is measured in newtons (N)?

A) Force
B) Energy
C) Mass
D) Electric current

(Total for Question 21 is 1 mark)

22

Sound waves are an example of which type of wave?

A) Transverse wave
B) Longitudinal wave
C) Electromagnetic wave
D) Standing wave only

(Total for Question 22 is 1 mark)

23

Ethan investigates whether the colour of a beaker's surface affects how quickly water inside it cools. He fills two identical beakers, one painted matt black and one shiny silver, with the same volume of water at the same starting temperature, and records the temperature of each every minute.

(a)State the independent variable in Ethan's investigation.(1)

(b)State the dependent variable in Ethan's investigation.(1)

(Total for Question 23 is 2 marks)

24

Complete the two missing words in these sentences about electricity.

(a)A component that resists the flow of electric current, transferring electrical energy to thermal energy, is called a ______.(1)

(b)The rate of flow of electric charge around a circuit is called ______.(1)

(Total for Question 24 is 2 marks)

25

A cyclist travels along a flat road at a constant speed. Explain, in terms of forces, why this constant speed means the forces acting on the cyclist must be balanced.

(Total for Question 25 is 3 marks)

26

Describe the job of each of these four parts of a simple electrical circuit: the cell (battery), the switch, the resistor (or lamp), and the connecting wires.

(Total for Question 26 is 4 marks)

27

A student has a bar magnet and a plotting compass.

(a)Name the two poles of a magnet.(1)

(b)State what happens when the north pole of one magnet is brought close to the north pole of another magnet.(1)

(c)Describe how the student could use the plotting compass to find the shape of the magnetic field around the bar magnet.(1)

(d)Explain why the magnetic field lines drawn around a bar magnet are closer together near its poles than further away.(1)

(Total for Question 27 is 4 marks)

28

The Earth rotates on its own axis once approximately every 24 hours, and orbits the Sun once approximately every 365.25 days. The Moon takes about 27 days to orbit the Earth.

(a)State what causes day and night on Earth.(1)

(b)State what causes the four seasons on Earth.(1)

(c)Explain why the Moon appears to shine, even though it does not produce its own light.(1)

(d)Explain why the appearance of the Moon (its phase) changes throughout its orbit of the Earth.(1)

(Total for Question 28 is 4 marks)

29

Zara investigated how the extension of a spring depends on the force applied. She hung different masses on the spring and measured its length each time. The spring's natural (unstretched) length was 10.0 cm.

Force (N): 0	1	2	3	4	5
Length of spring (cm): 10.0	12.0	14.0	16.0	18.0	21.0

(a)Calculate the extension of the spring when a force of 3 N is applied.(1)

(b)Describe the relationship between force and extension shown by the results between 0 N and 4 N.(1)

(c)Explain how the results show that the spring no longer obeys Hooke's law between 4 N and 5 N.(1)

(d)Suggest one way to improve the accuracy of measuring the length of the spring.(1)

(Total for Question 29 is 4 marks)

30

A cyclist freewheels (does not pedal) down a long, straight hill. Her speed increases at first, but after a while she reaches a steady, constant speed for the rest of the hill, even though the slope has not changed.

Explain, in terms of forces, why the cyclist's speed increases at first and then becomes constant.

(Total for Question 30 is 6 marks)

Mark scheme · CE.S-T4 Science: Full Practice Paper 4

Question 1

B1 B cao
Answer: B) Oxygen

Question 2

B1 C cao
Answer: C) Salmon

Question 3

(a) B1 the number of hours of sleep oe
(a) Answer: The number of hours of sleep each pupil got the previous night.
(b) B1 reaction time (measured with the ruler-drop test) oe
(b) Answer: Reaction time, measured using the ruler-drop test.

Question 4

(a) B1 virus cao
(a) Answer: Virus
(b) B1 bacterium (accept bacteria/bacterial cell)
(b) Answer: Bacterium

Question 5

B1 roots: absorb water and dissolved minerals from the soil oe
B1 xylem: transports water (and dissolved minerals) from the roots up to the leaves oe
B1 phloem: transports sugars (made by photosynthesis) to other parts of the plant that need them oe
Answer: The roots absorb water and dissolved minerals from the soil; the xylem transports this water and minerals up from the roots to the leaves; the phloem transports sugars made in photosynthesis to other parts of the plant.

Question 6

B1 variation means the differences that exist between individuals of the same species oe
B1 genetic cause: individuals inherit different alleles (genes) from their parents oe
B1 environmental cause: e.g. differences in diet, exercise, or health during growth affect characteristics such as height oe
Answer: Variation is the differences between individuals of the same species. It can be caused genetically, because individuals inherit different alleles from their parents, and environmentally, for example differences in diet or exercise during growth.

Question 7

B1 receptor: detects the stimulus (e.g. heat) and generates a nerve impulse oe
B1 sensory neurone: carries the nerve impulse from the receptor to the spinal cord (central nervous system) oe
B1 relay neurone: connects the sensory neurone to the motor neurone within the spinal cord oe
B1 motor neurone: carries the nerve impulse from the spinal cord to the effector (muscle), causing the response oe
Answer: The receptor detects the stimulus and generates a nerve impulse; the sensory neurone carries this impulse to the spinal cord; the relay neurone connects the sensory neurone to the motor neurone within the spinal cord; the motor neurone carries the impulse to the effector (muscle), causing the response.

Question 8

(a) B1 storage temperature oe
(a) Answer: Storage temperature.
(b) B1 any one of: the amount of water sprayed on each sample; the type/size of bread used; the length of time stored (one week) oe
(b) Answer: For example, the amount of water sprayed onto each bread sample.
(c) B1 as storage temperature increases (from 4 degC to 30 degC), the percentage of the surface covered in mould increases oe
(c) Answer: As storage temperature increases from 4 degC to 30 degC, the amount of mould growth increases.
(d) B1 very little mould grew at 4 degC (only 2%) compared with warmer temperatures, showing that a low temperature slows down the mould's growth/reproduction, keeping the bread fresher for longer oe
(d) Answer: At 4 degC only 2% of the surface grew mould, far less than at warmer temperatures, showing that a low temperature slows down the mould's growth, which keeps the bread fresher for longer.

Question 9

(a) B1 caterpillar cao
(a) Answer: Caterpillar
(b) B1 tertiary consumer (accept top predator)
(b) Answer: Tertiary consumer (top predator).
(c) B1 any one of: energy is lost as heat (thermal energy) through respiration; energy is lost in waste/faeces (egested, undigested material); energy is used for movement; not all of the caterpillar's body is eaten oe
(c) Answer: Some energy is lost as heat through the caterpillar's respiration (or in its faeces, or used for its movement).
(d) B1 500 kJ cao (working: 5000 * 0.10)
(d) Answer: 500 kJ

Question 10

(a) B1 small, dull petals (or no petals), and/or no nectar or scent oe
(a) B1 large amounts of small, light, smooth pollen, and/or a large, feathery stigma to catch pollen from the air oe
(a) Answer: For example: small, dull petals with no nectar or scent; large amounts of small, light, smooth pollen; a large, feathery stigma.
(b) B1 brightly coloured and/or scented petals, and/or nectar produced oe
(b) B1 pollen produced in smaller amounts, often sticky or spiky (to attach to insects), and/or stigma inside the flower oe
(b) Answer: For example: brightly coloured, scented petals that produce nectar; smaller amounts of sticky or spiky pollen; a stigma located inside the flower.

Question 11

B1 B cao
Answer: B) Evaporation

Question 12

B1 B cao
Answer: B) Water

Question 13

(a) B1 the type of metal (magnesium, zinc or copper) oe
(a) Answer: The type of metal.
(b) B1 the time taken for bubbling (the reaction) to stop oe
(b) Answer: The time taken for the bubbling to stop.

Question 14

(a) B1 alkaline (accept alkali)
(a) Answer: Alkaline
(b) B1 catalyst cao
(b) Answer: Catalyst

Question 15

B1 gas produced: hydrogen cao
B1 test: hold a lit splint to the mouth of the (test) tube; positive result is a squeaky pop oe
B1 products of metal + acid: a salt and hydrogen oe
Answer: The gas produced is hydrogen. Holding a lit splint to the mouth of the test tube gives a squeaky pop if hydrogen is present. Whenever a metal reacts with an acid, the two products formed are a salt and hydrogen.

Question 16

B1 limestone is subjected to intense heat and/or pressure deep underground oe
B1 this happens without the rock melting oe
B1 the limestone recrystallises, forming marble, a metamorphic rock with a different (interlocking crystal) structure from the original limestone oe
Answer: Limestone is subjected to intense heat and pressure deep underground, without melting. This causes it to recrystallise, forming marble, a metamorphic rock with a different, interlocking crystal structure from the original limestone.

Question 17

(a) B1 concentration of (hydrochloric) acid oe
(a) Answer: The concentration of the hydrochloric acid.
(b) B1 carbon dioxide cao
(b) Answer: Carbon dioxide
(c) B1 the line becomes flat/horizontal (levels off) - no more gas is produced oe
(c) Answer: The line on the graph becomes flat (horizontal), showing that no more gas is being produced.
(d) B1 the more concentrated acid has more acid particles in the same volume, so collisions between acid and marble (carbonate) particles happen more frequently, increasing the rate of reaction oe
(d) Answer: The 2 mol/dm³ acid has more acid particles in the same volume of solution, so collisions between the acid particles and the marble happen more often, making the reaction faster.

Question 18

(a) B1 1% cao (working: 100 - 78 - 21)
(a) Answer: 1%
(b) B1 burning fossil fuels (combustion), or deforestation oe
(b) Answer: Burning fossil fuels (combustion).
(c) B1 photosynthesis cao
(c) Answer: Photosynthesis
(d) B1 carbon dioxide is a greenhouse gas that traps some outgoing thermal (infrared) radiation from the Earth's surface, enhancing the greenhouse effect and warming the planet oe
(d) Answer: Carbon dioxide is a greenhouse gas: it traps some of the thermal radiation leaving the Earth's surface, enhancing the natural greenhouse effect and causing the planet to warm.

Question 19

(a) B1 magnesium + oxygen -> magnesium oxide cao
(a) Answer: Magnesium + oxygen -> magnesium oxide
(b) B1 2Mg(s) + O2(g) -> 2MgO(s) cao (correct formulae, balanced, correct state symbols all required)
(b) Answer: 2Mg(s) + O2(g) -> 2MgO(s)
(c) B1 3.2 g cao (working: 8.0 - 4.8)
(c) Answer: 3.2 g
(d) B1 no atoms are created or destroyed in a chemical reaction, they are only rearranged (joined together differently), so the total mass of reactants equals the total mass of products oe
(d) Answer: In a chemical reaction, atoms are never created or destroyed, only rearranged into new substances, so the total mass of the reactants (magnesium and oxygen) always equals the total mass of the product (magnesium oxide).

Question 20

(a) B1 element - it contains only one type of atom (oxygen atoms only) oe
(a) Answer: Element, because oxygen gas contains only oxygen atoms.
(b) B1 compound - it contains atoms of two different elements (carbon and oxygen) chemically joined together oe
(b) Answer: Compound, because carbon dioxide contains carbon and oxygen atoms chemically joined together.
(c) B1 mixture - it contains different substances (e.g. nitrogen, oxygen, carbon dioxide) that are not chemically joined together oe
(c) Answer: Mixture, because air contains several different substances, such as nitrogen and oxygen, that are not chemically bonded together.
(d) B1 since the gases in air are not chemically bonded, they can be separated by physical means, e.g. fractional distillation of liquefied air (cooling air until it liquefies, then separating the gases as they boil off at their different boiling points) oe
(d) Answer: Because the gases in air are not chemically bonded, they can be separated by physical means, such as cooling the air until it becomes a liquid and then separating the different gases as they boil off at their different boiling points (fractional distillation).

Question 21

B1 A cao
Answer: A) Force

Question 22

B1 B cao
Answer: B) Longitudinal wave

Question 23

(a) B1 the colour/surface of the beaker (matt black or shiny silver) oe
(a) Answer: The colour (surface finish) of the beaker.
(b) B1 the temperature of the water (as it cools over time) oe
(b) Answer: The temperature of the water in each beaker.

Question 24

(a) B1 resistor cao
(a) Answer: Resistor
(b) B1 (electric) current cao
(b) Answer: Current

Question 25

B1 travelling at a constant speed means the resultant (overall) force on the cyclist is zero oe
B1 this happens when the driving force (from pedalling, pushing the bike forward) is equal in size to the total resistive forces (friction and air resistance) acting backward oe
B1 if the driving force were greater than the resistive forces, there would be a resultant force forward and the cyclist would accelerate instead of staying at a constant speed oe
Answer: A constant speed means the resultant force on the cyclist is zero, so the forces are balanced: the forward driving force from pedalling must equal the backward resistive forces (friction and air resistance). If the driving force were greater, there would be a resultant force and the cyclist would accelerate instead.

Question 26

B1 cell (battery): provides the energy (potential difference/voltage) needed to push current around the circuit oe
B1 switch: opens or closes the circuit, turning the current on or off oe
B1 resistor (or lamp): resists the flow of current, usefully transferring electrical energy (e.g. to light or thermal energy) oe
B1 connecting wires: conduct current between the components, completing the circuit oe
Answer: The cell provides the energy that pushes current around the circuit; the switch opens or closes the circuit to turn the current on or off; the resistor or lamp resists current flow and usefully transfers electrical energy; the connecting wires conduct current between the components, completing the circuit.

Question 27

(a) B1 north (pole) and south (pole) - both needed
(a) Answer: North pole and south pole.
(b) B1 they repel (push apart/move away from each other) oe
(b) Answer: They repel each other.
(c) B1 place the compass near the magnet, mark the direction the needle points, move the compass to that new position and mark again; repeat to trace a full field line, and repeat from several starting points oe
(c) Answer: Place the compass near the magnet and mark the direction the needle points; move the compass to that new position and mark the direction again; repeat this to trace a complete field line, then repeat from several different starting points.
(d) B1 the magnetic field is strongest near the poles, and field lines drawn closer together represent a stronger magnetic field oe
(d) Answer: The magnetic field is strongest near the poles of the magnet, and field lines are drawn closer together to represent a stronger field, so they are closest together near the poles.

Question 28

(a) B1 the rotation of the Earth on its own axis oe
(a) Answer: The rotation of the Earth on its own axis.
(b) B1 the tilt of the Earth's axis (as it orbits the Sun) oe
(b) Answer: The tilt of the Earth's axis as it orbits the Sun.
(c) B1 the Moon reflects light from the Sun, and this reflected sunlight is what we see oe
(c) Answer: The Moon reflects sunlight, and it is this reflected light that we see from Earth.
(d) B1 as the Moon orbits the Earth, the fraction of its sunlit half that is visible from Earth changes, producing the different phases oe
(d) Answer: As the Moon orbits the Earth, the amount of its sunlit half that is visible from Earth changes, which is what produces the different phases, such as new moon, half moon and full moon.

Question 29

(a) B1 6.0 cm cao (working: 16.0 - 10.0)
(a) Answer: 6.0 cm
(b) B1 extension is directly proportional to force (Hooke's law) oe
(b) Answer: The extension is directly proportional to the force applied (Hooke's law).
(c) B1 the extension for the last 1 N added (from 4 N to 5 N) is 3.0 cm, larger than the constant 2.0 cm extension per 1 N seen at lower forces, showing extension is no longer proportional to force (the spring has passed its elastic limit) oe
(c) Answer: Between 4 N and 5 N the extension increases by 3.0 cm, more than the steady 2.0 cm per newton seen at lower forces, showing the extension is no longer proportional to force, so the spring has passed its elastic limit.
(d) B1 any valid method, e.g. view the scale at eye level to avoid parallax error, use a set square/pointer against the scale, or use a more precise measuring instrument oe
(d) Answer: View the ruler's scale at eye level (or use a set square against the scale) to avoid parallax error when reading the spring's length.

Question 30

Level 1 (1-2): Basic, isolated statement(s) about forces acting on the cyclist, with little or no linking to why she speeds up or why her speed later becomes constant.
Level 2 (3-4): Some relevant forces (e.g. weight, friction, air resistance) are identified and partly linked to the cyclist's changing speed, but the explanation of why the speed becomes constant is incomplete or not fully linked to resultant force.
Level 3 (5-6): A clear, logically linked explanation using the idea of resultant force to explain both the initial increase in speed and the later constant (terminal) speed.
Indicative content:
- At the start, the component of gravity (weight) acting down the slope is greater than the total resistive forces (friction and air resistance) acting on the cyclist.
- This means there is a resultant (unbalanced/net) force acting in the direction of travel, so the cyclist accelerates (speeds up).
- As the cyclist's speed increases, air resistance (and friction) increases.
- Eventually the resistive forces increase until they balance the forward component of gravity acting down the slope.
- When the forces are balanced, the resultant force on the cyclist is zero.
- With zero resultant force there is no further acceleration, so the cyclist travels at a constant (terminal) speed for the rest of the hill.

Science: Full Practice Paper 4 - Worksheets, Questions and Revision

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CE.S-T4 Science: Full Practice Paper 4

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