KUULCHAT
SCIENCE MOCK
OBJECTIVE TEST
THEORY QUESTIONS
1.
a)
State three ways in which crop rotation is important in crop production.
b)
State three properties of the image formed by a plane mirror.
c)
i)
What is photosynthesis?
ii)
Explain briefly why a digestive system is necessary in humans.
d)
Give the systematic name of the following compounds:
i)
α)
MgCl2;
β)
FeS.
ii)
What is an element?
iii)
What is the name given to a solid mixture?
a)
Importance of crop rotation
1. Increases soil fertility/Adds nitrogen to soil
2. Enhances soil structure
3. Prevents soil erosion
4. Improves soil nutrients and nutrient uptake regulation
5. Controls the spread of pests and diseases
6. Controls weed easily
7. There is effective use of the land
8. Harvest of different types of crops on the same piece of land
b)
Properties of image formed by a plane mirror
1. It is virtual
2. It is upright
3. Same size/shape as the object
4. The distance of the object from the plane mirror is the same as the distance of the image from the plane mirror
5. It is laterally inverted
c)
i)
Photosynthesis is the process by which green plant produces their own food/carbohydrate/glucose/starch using carbon dioxide and water with the presence of sunlight and chlorophyll.
ii)
Importance of digestive system
It breaks down food so that it can be used by the body for energy/cell growth or repair
d)
i)
Systematic Names
α)
MgCl2 → Magnesium Chloride
β)
FeS → Iron (II) sulphide
ii)
Element is a simple substance that cannot be broken down into smaller parts or changed into another substance or a substance whose atoms are of the same kind
iii)
The name given to a solid mixture is an alloy
2.
a)
i)
State two physical properties of water.
ii)
Using litmus paper, explain why water is neutral.
b)
Give one function of each of the following nutrients in plants:
i)
Nitrogen;
ii)
Potassium.
c)
i)
State two human activities that disrupt the carbon cycle.
ii)
State two effects of the disruption of the carbon cycle on the environment.
d)
i)
What is density of a body?
ii)
A body of mass 50kg has a density of 2kg/m3. Calculate the volume of the body.
a)
i)
Physical properties of water
1. Odourless
2. Colourless
3. Tasteless/insipid
4. Freezes at 0oC
5. Boils at 100oC
6. Universal solvent
7. Exists in three states
8. Has a density of 1g/cm3 (at 4oC)
9. It is transparent
10. It has a neutral pH/pH = 7
11. High surface tension
ii)
Why water is neutral
When red litmus paper or blue litmus paper is dropped in a sample of water, there is no change in colour.
b)
i)
Functions of nitrogen in plants
1. For plant growth/vegetative growth
2. Increases yield of straw
3. A constituent of organic compound of plants
4. For plant development
5. Increases seed and fruit production
6. To make proteins
7. To make chlorophyll
ii)
Functions of potassium in plants
1. Plays an important role in plant metabolism
2. Plays an important role in translocation of starch to growing parts
3. Plays an important role in carbohydrate formation
4. Neutralization of organic acids
5. Strengthens straw and stalk of plants
6. Aids absorption of nutrients
7. Helps to reduce diseases in plants
8. Helps to produce quality fruit and promotes seed development
9. Activates enzymes for photosynthesis and respiration
10. Helps build proteins
11. Aids absorption of nutrients
c)
i)
Human activities that disrupt the carbon cycle
1. Destruction of forest/cutting of trees/lumbering
2. Bush burning
3. Burning of fossil fuels
ii)
Effects of the disruption of the carbon cycle on the environment
1. Global warming/rise in temperature/greenhouse effect/affects climate
2. Reduction in oxygen
3. Rise in sea level/flooding/melting of ice
4. Animals/plants become endangered/extinct
5. Prolonged drought
6. Reduction in rainfall
d)
i)
Density is the mass per unit volume of a body
OR
Density =
ii)
Density =
Density x Volume = Mass
Divide both sides by Density
Volume =
Mass = 50 kg
Density = 2kg/m3
Volume = = 25 m3
3.
a)
The diagram below is an illustration of a longitudinal section of a canine tooth in humans.
Study the diagram carefully and answer the questions that follow.
i)
Name each of the parts labelled I, II, III and IV.
ii)
What is the function of each of the parts labelled I and III?
iii)
Which of the labelled parts could be affected by tooth decay?
iv)
State three ways by which tooth decay may be prevented.
b)
The diagram below is an illustration of a scientific phenomenom which occurs in nature.
Study the diagram carefully and answer the questions that follow.
i)
What phenomenom does the diagram illustrate?
ii)
Identify each of the parts labelled I, II, III, IV and V.
iii)
Explain why an object at the bottom of a pond appears closer to the surface than it actually is.
c)
The diagram below is an illustration of an experiment performed to separate the components of muddy water.
Study the diagram carefully and answer the questions that follow.
i)
Name each of the parts labelled I, II and III.
ii)
State the function of the part labelled II.
iii)
Name the substance obtained as the filtrate.
iv)
State three physical properties of the filtrate.
v)
Name two other materials that could be used in place of the part labelled II.
d)
The diagram below is an illustrates a farmland on a sloppy area.
Study the diagram carefully and answer the questions that follow.
i)
What process is likely to occur on the farmland when it rains heavily?
ii)
State two farming practices that can also lead to the process mentioned in (i).
iii)
List four farming practices that could be used to control the process mentioned in (i).
iv)
Mention three soil resources that would be depleted from the farmland when it rains heavily.
a)
i)
I → Crown or Enamel
II → Dentine
III → Cement or Periodontal membrane
IV → Jaw bone or Root
V → Pulp Cavity
ii)
Functions of I (Crown or Enamel)
1. Protect teeth from harmful bacteria
2. Enables teeth withstand pressure of chewing
3. Cutting/chewing/protect dentine/protect pulp cavity
Functions of III (Cement or Periodontal membrane)
Holds tooth firmly in socket or jaw bone or supports the tooth
iii)
The part affected by tooth decay is V (Pulp Cavity)
iv)
Prevention of Tooth decay
1. Avoid using sharp-pointed objects
2. Avoid having dry mouth
3. Use water containing flourides to wash teeth/mouth
4. Avoid smoking
5. The teeth should be cleaned regularly after each meal/remove food particles from the teeth/flossing
6. Wash the mouth vigorously after each meal
7. Regular visit the dentist
8. Avoid eating too hot food
9. Avoid eating too much sugary food
10. Avoid eating too cold food
b)
i)
The phenomenon illustrated is refraction of light
ii)
I → Normal
II → Incident ray
III → Angle of incidence
IV → Angle of refraction
V → Refracted ray
iii)
Why object appears closer to surface
Rays from the object at the bottom are bent away from the normal as they come out of the water. In a straight line, these rays appear to come from a point above the bottom
c)
i)
I → Retort/clamp stand
II → filter paper
III → funnel
ii)
Function of II (Filter paper)
1. To filter solid or insoluble particles or residue
2. To separate the mud,solid or insoluble particles from the water
3. To prevent residue/solid/insoluble particles/mud from entering the filtrate
iii)
Name of filtrate is water
iv)
Physical properties of filtrate (Water)
1. It has a density of 1 gcm-3 or 1000 kg m-3
2. It boils at 100 oC
3. It freezes at 0 oC (at 1 atm)
4. It is colourless
5. It is tasteless or insipid
6. It is odourless
7. It has a high surface tension
8. It is a universal solvent
9. It is transparent
10. It has a neutral pH or pH of 7
11. It exists in three states (solid, liquid and gas)
v)
Other materials that could be used instead of filter paper
1. Cotton wool
2. Foam
3. Glass wool
4. Clean/white cloth
d)
i)
Process likely to occur is erosion
ii)
Farming practices that could lead to the process occuring (erosion)
1. Bush burning
2. Deforestation
3. Continuous cropping
4. Crop removal
5. Excessive use of chemicals or inorganic fertilizers
6. Overgrazing
7. Cultivating or ploughing along slope
iii)
Farm practices that could control the process (erosion)
1. Planting cover crops
2. Terracing
3. Cultivating or ploughing slope or contour
4. Heavy mulching
5. Construction of drainage channels
6. Planting trees beside farm
7. Strip cropping
8. Contour bunding
iv)
Soil resources depleted
1. Soil organisms
2. Nutrients
3. Mineral matter
4. Soil particles or mineral matter
5. Growing crops
6. Air
7. Organic matter or humus
4.
a)
i)
What is a mixture?
ii)
Explain why some mixtures are thoroughly stirred before they are used.
b)
i)
What is reflection of light?
ii)
State two characteristics of the images formed by plane mirrors.
c)
i)
What is a fertilizer?
ii)
Give one example of an inorganic fertilizer.
d)
i)
What is indiscriminate sex?
ii)
State two dangers of indiscriminate sex on humans.
a)
i)
Mixture is what is formed when two or more substances are put together/combine physically.
ii)
Why some mixtures are thoroughly stirred before they are used
Mixtures are thoroughly stirred to make a homegenous/uniform mixture
OR
Mixtures are thoroughly stirred to make even/uniform concentration
b)
i)
Reflection of light is the bouncing of light from a surface.
ii)
Characteristics of the images formed by plane mirrors
1. It is erect (upright)
2. It is virtual
3. It is laterally inverted
4. Same distance behind mirror as object is in front of mirror
5. Same size and shape as the object
c)
i)
Fertilizer is any substance which is applied to the soil or plant to supply nutrients for plant growth.
ii)
Examples of an inorganic fertilizer
1. Urea
2. Muriate of potash
3. Single super phosphate (SSP)/sulphate of ammonia
4. NPK
d)
i)
Indiscriminate sex is the act of having sexual intercourse with different/many/multiple partners.
ii)
Dangers of indiscriminate sex on humans
1. Acquiring sexually transmitted diseases
2. Unwanted pregnancy/becoming pregnant
3. Causing abortion
5.
a)
The funnels in the diagram below contain equal amounts of different types of soil labelled K, L and M. Equal volumes of water were poured onto each soil at the same time and allow to drain for 20 minutes.
Study the diagram carefully and answer the questions that follow.
i)
What is the aim of the experiment?
ii)
Which soil has the highest rate of drainage?
iii)
Which soil has the highest water retention capacity?
iv)
Which soil is mostly likely to lose water and dry faster after rainfall?
v)
Which soil is mostly likely to be waterlogged after rainfall?
vi)
Which of the soil types would be suitable for maize cultivation?
b)
The diagram below illustrates hazard symbols labelled I, II, III and IV.
Study the diagram carefully and answer the questions that follow.
i)
What does each of the symbols labelled I, II, III and IV represent?
ii)
Name one substance each that is associated with:
α)
I;
β)
II;
γ)
III.
iii)
Name the place where the symbol labelled IV is often displayed.
iv)
Which of the symbol(s) is/are found on chemical containers?
c)
The diagram below illustrations of devices used to do work easily.
Study the diagram carefully and answer the questions that follow.
i)
Give a general name for the devices.
ii)
Identify each of the devices labelled A, B, C and D.
iii)
Name the parts labelled I, II and III of device A when it is considered as a lever.
iv)
What does the arrow represent in the device labelled B?
v)
Name the type of work done with each of the device labelled:
α)
C;
β)
D.
d)
The diagram below illustrates the digestive system in humans.
Study the diagram carefully and answer the questions that follow.
i)
Name each of the parts labelled I, II, III, IV and V.
ii)
Name the part(s) of the digestive system where:
α)
digestion of food substances occur;
β)
digested food is absorbed into the bloodstream.
iii)
Name the end-products of the digestion that is absorbed into the bloodstream.
a)
i)
To compare the rate of water drainage in different types of soil/compare the water holding capacity of types of soils.
ii)
Soil K/Sandy soil
iii)
Soil M/Clayey soil
iv)
Soil K/Sandy soil
v)
Soil M/Clayey soil
vi)
Soil L/Loamy soil
b)
i)
I → toxic/poisonous
II → corrosive
III → flammable/inflammable
IV → no smoking/no naked flame
ii)
α)
Toxic/poisonous substances (I)
1. Carbon monoxide
2. Hydrogen sulphide
3. Chlorine
4. Sodium
5. Potassium
6. Cyanide compounds
7. Mercury compounds
8. Iodine
9. Carbon tetrachloride
10. Crude oil
11. Bromine
12. Lead compounds
13. Copper sulphate
14. Ammonia
15. Carbon tetrachloride(CCl4)
β)
Corrosive substances (II)
1. Concentrated hydrochloric acid
2. Sodium hydroxide
3. Potassium hydroxide
4. Nitric acid
5. Ammonium hydroxide/Ammonia
γ)
Flammable substances (III)
1. Gasoline/Petrol
2. Ethanol
3. Acetone
4. Liquid nail polish
5. L.P.G.
iii)
Places where no smoking (IV) is displayed
1. Petrol station/filling station
2. Gas station
3. Petrol tankers
4. Gas tankers
5. Public places/Any named public place e.g hospital,hotels etc.
6. Fuel storage areas
iv)
I, II and III
c)
i)
Simple machine
ii)
A → Wheelbarrow
B → Inclined plane
C → Pulley
D → Gear
iii)
I → Effort
II → Load
III → Pivot/Fulcrum
iv)
Effort
v)
α)
Use of pully
Lifting/raising loads up/lowering loads
β)
Use of gear
Change speed/direction/movement
d)
i)
I → Stomach
II → Small intestine/ileum
III → Large intestine/colon
IV → Rectum
V → Oesophagus/gullet
ii)
α)
Stomach/mouth/duodenum/ileum/small intestine
β)
Small intestine/ileum
iii)
End-products of digestion
1. Amino acid
2. Glucose
3. Fatty acids/glycerol
6.
a)
State two precautions that should be taken to prevent the spread of each of the following diseases:
i)
cholera
ii)
smallpox
b)
Describe how you would test for starch in a leaf.
c)
i)
Explain why an inclined plane is classified as a machine.
ii)
Give two reasons why the output energy of a machine is always less than the input energy.
d)
Draw and label the structure of an atom containing three electrons. Indicate the charges of the particles.
a)
i)
Precautions taken to prevent cholera
1. Ensuring refuse/sewage does not contaminate food and water sources
2. Boiling stream/rivers/ground water before drinking
3. Washing hands after visiting the toilet
4. Washing hands/clothing and body after touching cholera patients
5. Keeping environment clean
6. Vaccination
7. Isolating cholera patients
8. Eating hot food
9. Reporting cholera cases to health authorities for action
ii)
Precautions taken to prevent smallpox
1. Living in well ventilated surroundings
2. Avoid spitting in public
3. Wearing neat/clean clothing
4. Avoiding dusty places
5. Vaccination/inoculation
6. Isolating smallpox patients
7. Reporting smallpox cases to health authorities for action
b)
How to test for starch in a leaf
1. Dip the leaf in boiling water for some time
2. Put the boiled leaf in alcohol/methylated spirit
3. Wash in warm water
4. Dip in iodine solution
5. The leaf turns blue black which confirms the presence of starch in the leaf
c)
i)
Why an inclined plane is classified as a machine
1. It enables work to be done easier/faster
2. A heavier load could be overcome with a smaller effort by pushing it up the plane than by lifting it directly upwards
ii)
Reasons why the output energy of a machine is always less than the input energy
1. Part of the input energy is used to overcome friction
2. Part of the input energy is used to overcome inertia
3. Part of the input energy is used to overcome gravitational force
d)
