1
Q
What is movement in the context of living organisms?
A
An action by an organism or part of an organism causing a change of position or place
Movement is one of the key characteristics of living organisms.
2
Q
Define respiration as a characteristic of living organisms.
A
The chemical reactions in cells that break down nutrient molecules and release energy for metabolism
Respiration is essential for energy production in living organisms.
3
Q
What does sensitivity refer to in living organisms?
A
The ability to detect and respond to changes in the internal or external environment
Sensitivity allows organisms to adapt to their surroundings.
4
Q
Define growth in the context of living organisms.
A
A permanent increase in size and dry mass
Growth is a fundamental characteristic of all living organisms.
5
Q
What is reproduction in living organisms?
A
The processes that make more of the same kind of organism
Reproduction is essential for the continuation of a species.
6
Q
Define excretion as a characteristic of living organisms.
A
The removal of waste products of metabolism and substances in excess of requirements
Excretion is crucial for maintaining homeostasis.
7
Q
What does nutrition mean in the context of living organisms?
A
The taking in of materials for energy, growth, and development
Nutrition is vital for sustaining life and supporting growth.
8
Q
List the structures compared between plant cells and animal cells.
A
- Cell wall
- Cell membrane
- Nucleus
- Cytoplasm
- Chloroplasts
- Ribosomes
- Mitochondria
- Vacuoles
Understanding these structures is essential for studying cell biology.
9
Q
Describe the structure of a bacterial cell.
A
- Cell wall
- Cell membrane
- Cytoplasm
- Ribosomes
- Circular DNA
- Plasmids
Bacterial cells differ significantly from plant and animal cells.
10
Q
What is the formula for magnification?
A
magnification = image size / actual size
This formula is used to calculate the size of biological specimens.
11
Q
Describe diffusion.
A
The net movement of particles from a region of higher concentration to a region of lower concentration
Diffusion is a fundamental process in biology for the movement of substances.
12
Q
What is osmosis?
A
The net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane
Osmosis is crucial for maintaining cell turgor and function.
13
Q
Define active transport.
A
The movement of particles through a cell membrane from a region of lower concentration to a region of higher concentration, using energy from respiration
Active transport is essential for nutrient uptake in cells.
14
Q
List the chemical elements that make up carbohydrates.
A
- Carbon
- Hydrogen
- Oxygen
Carbohydrates are essential macromolecules for energy.
15
Q
What is the role of enzymes in biological reactions?
A
Proteins that function as biological catalysts in metabolic reactions
Enzymes speed up chemical reactions without being consumed.
16
Q
State the word equation for photosynthesis.
A
carbon dioxide + water → glucose + oxygen
Photosynthesis is vital for energy production in plants.
17
Q
What are the main organs of the digestive system?
A
- Mouth
- Oesophagus
- Stomach
- Small intestine
- Large intestine
These organs work together to process food and absorb nutrients.
18
Q
Describe physical digestion.
A
The breakdown of food into smaller pieces without chemical change to the food molecules
Physical digestion increases the surface area for enzymes.
19
Q
What is the function of xylem?
A
Transport of water and mineral ions, and support
Xylem is essential for plant hydration and nutrient transport.
20
Q
What is the role of red blood cells?
A
Transporting oxygen, including the role of haemoglobin
Red blood cells are crucial for oxygen delivery throughout the body.
21
Q
Define a pathogen.
A
A disease-causing organism
Pathogens can lead to various diseases in hosts.
22
Q
What is a transmissible disease?
A
A disease in which the pathogen can be passed from one host to another
Understanding transmission is key to controlling outbreaks.
23
Q
Describe the body defences against pathogens.
A
- Skin
- Hairs in the nose
- Mucus
- Stomach acid
- White blood cells
These components work together to protect the body from infections.
24
Q
Explain the importance of a clean water supply in controlling the spread of disease.
A
Prevents waterborne diseases
Access to clean water is crucial for maintaining health and hygiene.
25
True or false: **Hygienic food preparation** is important for controlling the spread of disease.
TRUE
## Footnote
Proper food handling reduces the risk of foodborne illnesses.
26
Fill in the blank: **Active immunity** is gained after an infection by a pathogen or by _______.
vaccination
## Footnote
Vaccination stimulates the immune system to produce antibodies.
27
Identify the parts of the **breathing system**.
* Lungs
* Diaphragm
* Ribs
* Intercostal muscles
* Larynx
* Trachea
* Bronchi
* Bronchioles
* Alveoli
## Footnote
These structures are essential for gas exchange in humans.
28
Describe the features of **gas exchange surfaces** in humans.
* Large surface area
* Thin surface
* Good blood supply
* Good ventilation with air
## Footnote
These features enhance the efficiency of gas exchange.
29
State the word equation for **aerobic respiration**.
glucose + oxygen → carbon dioxide + water
## Footnote
This equation summarizes the process of aerobic respiration.
30
Describe a **drug**.
Any substance taken into the body that modifies or affects chemical reactions
## Footnote
Drugs can have various effects on bodily functions.
31
State that **antibiotics** kill bacteria but do not affect _______.
viruses
## Footnote
Antibiotics are specifically designed to target bacterial infections.
32
Describe **pollination**.
The transfer of pollen grains from an anther to a stigma
## Footnote
Pollination is a crucial step in the reproductive process of flowering plants.
33
Identify the parts of the **male reproductive system**.
* Testes
* Scrotum
* Sperm ducts
* Prostate gland
* Urethra
* Penis
## Footnote
These structures are involved in the production and delivery of sperm.
34
Describe the **carbon cycle**.
* Photosynthesis
* Respiration
* Feeding
* Decomposition
* Formation of fossil fuels
* Combustion
## Footnote
The carbon cycle illustrates the movement of carbon through different environmental compartments.
35
Describe a **food chain**.
Shows the transfer of energy from one organism to the next, beginning with a producer
## Footnote
Food chains illustrate the flow of energy in an ecosystem.
36
Describe a **consumer**.
An organism that gets its energy by feeding on other organisms
## Footnote
Consumers can be classified as primary, secondary, or tertiary.
37
State the **distinguishing properties** of solids, liquids, and gases.
* Solids: fixed shape and volume
* Liquids: fixed volume, shape of container
* Gases: neither fixed shape nor volume
## Footnote
These properties are based on particle arrangement and movement.
38
Define **electrolysis**.
The decomposition of an ionic compound by the passage of an electric current
## Footnote
Electrolysis is used in various applications, including electroplating and the production of chemicals.
39
State that an **exothermic reaction** transfers thermal energy to the surroundings leading to a _______ in temperature.
increase
## Footnote
Exothermic reactions release energy, often in the form of heat.
40
Describe the effect on the **rate of reaction** of changing the concentration of solutions.
Increasing concentration increases the rate of reaction
## Footnote
More reactant particles lead to a higher frequency of collisions.
41
What is the role of a **catalyst** in a chemical reaction?
Increases the rate of a reaction and is unchanged at the end
## Footnote
Catalysts lower the activation energy required for reactions.
42
List practical methods for investigating the **rate of a reaction**.
* Change in mass of a reactant or product
* Formation of a gas
## Footnote
These methods help quantify how quickly reactions occur.
43
Describe **collision theory** in terms of:
(a) number of particles per unit volume
(b) frequency of collisions between particles
(c) kinetic energy of particles
(d) activation energy, Ea.
Collision theory explains how reactions occur based on:
* Number of particles per unit volume
* Frequency of collisions
* Kinetic energy
* Activation energy
## Footnote
Higher energy and more frequent collisions increase reaction rates.
44
Define **redox reactions**.
Involve simultaneous oxidation and reduction
## Footnote
Redox reactions are crucial in various chemical processes.
45
What is **oxidation** defined as?
Gain of oxygen
## Footnote
Oxidation is often accompanied by a loss of electrons.
46
What is **reduction** defined as?
Loss of oxygen
## Footnote
Reduction is often associated with a gain of electrons.
47
Identify the **characteristic properties of acids**.
* React with metals
* React with bases
* React with carbonates
## Footnote
Acids have distinct behaviors that define their chemical nature.
48
What is the effect of acids on **indicators** like litmus and methyl orange?
* Litmus: Turns red
* Methyl orange: Turns red
## Footnote
Indicators change color in response to acidic conditions.
49
What are **bases** defined as?
Oxides or hydroxides of metals; alkalis are soluble bases
## Footnote
Bases neutralize acids and have specific properties.
50
Describe the **characteristic properties of bases**.
* React with acids
* Change color of indicators
## Footnote
Bases are essential in neutralization reactions.
51
Classify **oxides** as either acidic or basic.
* Acidic: SO2, CO2
* Basic: CuO, CaO
## Footnote
The classification relates to metallic and non-metallic character.
52
Describe the **preparation of soluble salts** by reaction of an acid with:
(a) an alkali by titration
(b) excess metal
(c) excess insoluble base
(d) excess insoluble carbonate.
* Acid + alkali by titration
* Acid + excess metal
* Acid + excess insoluble base
* Acid + excess insoluble carbonate
## Footnote
These methods are used to produce various soluble salts.
53
What is the **Periodic Table**?
An arrangement of elements in periods and groups in order of increasing proton number
## Footnote
The table reflects the periodicity of element properties.
54
Describe the **Group I alkali metals**.
* Soft metals
* Decreasing melting point down the group
* Increasing density down the group
* Increasing reactivity with water
## Footnote
These trends are important for understanding alkali metal behavior.
55
What are the **Group VII halogens** at room temperature and pressure?
* Chlorine: Pale yellow-green gas
* Bromine: Red-brown liquid
* Iodine: Grey-black solid
## Footnote
Halogens exhibit distinct physical states and colors.
56
Describe the **transition elements**.
* High densities
* High melting points
* Form colored compounds
* Often act as catalysts
## Footnote
Transition metals have unique properties that make them useful in various applications.
57
What are the **Group VIII noble gases** characterized by?
Unreactive, monatomic gases
## Footnote
Their stability is due to their complete electronic configuration.
58
Compare the general **physical properties of metals and non-metals**.
* Thermal conductivity
* Electrical conductivity
* Malleability and ductility
* Melting points and boiling points
## Footnote
Understanding these properties helps in material selection.
59
What are the **fossil fuels**?
* Coal
* Natural gas
* Petroleum
## Footnote
Fossil fuels are primary energy sources derived from ancient organic matter.
60
Describe the **separation of petroleum** into useful fractions.
By fractional distillation
## Footnote
This process allows for the extraction of various hydrocarbons based on boiling points.
61
What is a **polymer**?
Large molecules built up from many smaller molecules called monomers
## Footnote
Polymers have diverse applications in materials science.
62
What is the **greenhouse effect** caused by carbon dioxide and methane?
Absorption, reflection, and emission of thermal energy
## Footnote
Greenhouse gases trap heat in the atmosphere, contributing to global warming.
63
What conditions are required for the **rusting of iron**?
Presence of oxygen and water
## Footnote
Rusting is an electrochemical process that deteriorates iron.
64
State some common **barrier methods** to prevent rusting.
* Painting
* Greasing
* Coating with plastic
## Footnote
These methods exclude oxygen and water to protect iron.
65
What are the **measurements** included in the measurement of time, temperature, mass, and volume?
* stop-watches
* thermometers
* balances
* burettes
* volumetric pipettes
* measuring cylinders
* gas syringes
## Footnote
These instruments are essential for accurate scientific measurements.
66
Define a **solvent**.
A substance that dissolves a solute
## Footnote
Solvents are crucial in creating solutions.
67
Define a **solute**.
A substance that is dissolved in a solvent
## Footnote
Solutes are the components that change the properties of the solvent.
68
Define a **solution**.
A mixture of one or more solutes dissolved in a solvent
## Footnote
Solutions are homogeneous mixtures that can be liquid, gas, or solid.
69
What is a **saturated solution**?
A solution containing the maximum concentration of a solute dissolved in the solvent at a specified temperature
## Footnote
This indicates that no more solute can be dissolved in the solvent.
70
Define **residue**.
A solid substance that remains after evaporation, distillation, filtration, or any similar process
## Footnote
Residue is often analyzed to determine the composition of the original mixture.
71
Define **filtrate**.
A liquid or solution that has passed through a filter
## Footnote
Filtrate is the result of the filtration process.
72
Describe how **paper chromatography** is used.
To separate mixtures of soluble coloured substances using a suitable solvent
## Footnote
This technique is widely used in laboratories for analysis.
73
What does the **Rf equation** represent?
Rf = distance travelled by substance / distance travelled by solvent
## Footnote
Rf values help in identifying substances based on their movement in chromatography.
74
What are the methods of **separation and purification**?
* suitable solvent
* filtration
* crystallisation
* simple distillation
* fractional distillation
## Footnote
These methods are essential in chemical analysis and preparation.
75
How do you identify the **anions** carbonate, chloride, bromide, and sulfate?
* Carbonate: reaction with dilute acid and test for CO2
* Chloride, Bromide, Iodide: acidify with dilute nitric acid, add aqueous silver nitrate
* Sulfate: acidify with dilute nitric acid, add aqueous barium nitrate
## Footnote
These tests are fundamental in qualitative analysis.
76
What tests are used to identify **cations**?
* Ammonium: using aqueous sodium hydroxide
* Calcium: using aqueous sodium hydroxide
* Copper(II): using aqueous sodium hydroxide
* Iron(II): using aqueous sodium hydroxide
* Iron(III): using aqueous sodium hydroxide
* Zinc: using aqueous sodium hydroxide
## Footnote
These tests help in determining the presence of specific metal ions.
77
What tests are used to identify **gases**?
* Ammonia: using damp red litmus paper
* Carbon dioxide: using limewater
* Chlorine: using damp litmus paper
* Hydrogen: using a lighted splint
* Oxygen: using a glowing splint
## Footnote
These tests are essential for gas identification in laboratory settings.
78
What is the **flame test** used for?
To identify cations such as lithium, sodium, potassium, and copper(II)
## Footnote
The flame color produced helps in identifying the specific metal ions.
79
Define **speed**.
Distance travelled per unit time
## Footnote
Speed is a fundamental concept in physics related to motion.
80
What is the equation for **average speed**?
Average speed = total distance travelled / total time taken
## Footnote
This equation is used to calculate the speed of an object over a period.
81
What does a **distance-time graph** indicate?
* At rest: horizontal line
* Constant speed: straight line
* Accelerating: curve upwards
## Footnote
The shape of the graph provides insights into the motion of the object.
82
What is **acceleration** defined as?
Change in speed per unit time
## Footnote
Acceleration indicates how quickly an object is speeding up or slowing down.
83
What is the approximate value of **gravitational field strength g** near the Earth's surface?
Approximately 9.8 m/s²
## Footnote
This value is crucial for calculations involving weight and gravitational force.
84
Define **density**.
Mass per unit volume
## Footnote
Density is a key property that determines whether an object will float or sink.
85
What is the equation for **density**?
ρ = m / V
## Footnote
This equation is used to calculate the density of various substances.
86
What is the relationship between **mass** and **weight**?
* Mass: quantity of matter in an object
* Weight: gravitational force on an object with mass
## Footnote
Understanding this relationship is fundamental in physics.
87
What does the equation **F = ma** represent?
The relationship between force, mass, and acceleration
## Footnote
This equation is a cornerstone of Newton's second law of motion.
88
What is **thermal conduction**?
Transfer of thermal energy through atomic or molecular lattice vibrations
## Footnote
Good conductors allow heat to pass through easily, while insulators do not.
89
What is **convection**?
An important method of energy transfer in liquids and gases
## Footnote
Convection occurs due to density changes in the fluid.
90
What is the effect of **thermal radiation**?
Transfer of thermal energy that does not require a medium
## Footnote
This process is primarily due to infrared radiation.
91
What is the definition of **power**?
Work done per unit time or energy transferred per unit time
## Footnote
Power is a measure of how quickly work is done or energy is transferred.
92
What is the equation for **pressure**?
p = F / A
## Footnote
Pressure is defined as force applied per unit area.
93
What are the **three basic methods** of heat transfer?
* Conduction
* Convection
* Radiation
## Footnote
These methods describe how heat is transferred in different contexts.
94
True or false: **Waves transfer matter** as they transfer energy.
FALSE
## Footnote
Waves transfer energy without transferring matter.
95
For a **transverse wave**, the direction of vibration is at _______ to the direction of propagation.
right angles
## Footnote
Examples include electromagnetic radiation, water waves, and seismic S-waves.
96
For a **longitudinal wave**, the direction of vibration is _______ to the direction of propagation.
parallel
## Footnote
Examples include sound waves and seismic P-waves.
97
List the **features of a wave**.
* Wavelength
* Frequency
* Crest (peak)
* Trough
* Amplitude
* Wave speed
## Footnote
These features describe the characteristics of waves.
98
What is the equation for **wave speed**?
v = f λ
## Footnote
This equation relates wave speed (v), frequency (f), and wavelength (λ).
99
Define **refraction**.
Change in direction of a light ray passing from one medium to another
## Footnote
Refraction occurs due to a change in speed.
100
What are the characteristics of an **optical image** formed by a vertical plane mirror?
* Same size
* Same distance from mirror
* Laterally inverted
## Footnote
These characteristics describe how images appear in mirrors.
101
What is the **principal focus** of a thin converging lens?
The point where parallel rays of light converge
## Footnote
This is a key concept in optics related to lens behavior.
102
List the **seven colors** of the visible spectrum in order of frequency.
* Red
* Orange
* Yellow
* Green
* Blue
* Indigo
* Violet
## Footnote
These colors represent the dispersion of light.
103
What are the **main regions** of the electromagnetic spectrum?
* Radio
* Microwave
* Infrared
* Visible
* Ultraviolet
* X-ray
* Gamma
## Footnote
These regions are ordered by frequency and wavelength.
104
True or false: All **electromagnetic waves** travel at different speeds in a vacuum.
FALSE
## Footnote
All electromagnetic waves travel at the same high speed in a vacuum.
105
What is the approximate speed of **electromagnetic waves** in a vacuum?
3.0 × 10^8 m/s
## Footnote
This is a fundamental constant in physics.
106
Describe the **longitudinal nature** of sound waves.
Sound waves consist of compressions and rarefactions
## Footnote
Compressions are regions of higher pressure, while rarefactions are regions of lower pressure.
107
What is the approximate range of **frequencies audible to humans**?
20 Hz to 20 kHz
## Footnote
This range defines human hearing capabilities.
108
Define **electric current**.
The flow of charge
## Footnote
Electric current in metals is related to the flow of electrons.
109
What is the unit of **electrical charge**?
Coulombs
## Footnote
Charge is a fundamental property of matter.
110
What is the relationship between **voltage** and electric current?
Voltage is the cause of current in the circuit
## Footnote
Voltage is measured in volts (V).
111
What does the equation **R = V/I** represent?
Resistance
## Footnote
This equation relates resistance (R), voltage (V), and current (I).
112
What is the **heating effect of current**?
The generation of heat due to the flow of electric current
## Footnote
This effect can lead to hazards if not managed properly.
113
What is the purpose of a **fuse** in an electrical circuit?
To protect against excess current
## Footnote
Fuses are designed to break the circuit when current exceeds a safe level.
114
What do **cells and batteries** do?
Transfer chemical energy into electrical energy
## Footnote
This conversion is essential for powering electrical devices.
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