Plant Life
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Photosynthesis process
SubtopicPhotosynthesis process under Plant Life for Grade 7 ICSE.
Preview questions (no answers)
- 1.
What does the word 'synthesis' in photosynthesis mean?
A.To break down
B.To put together
C.To light up
D.To drink
- 2.
Why does a leaf look green when sunlight falls on it?
A.It absorbs all colors of light
B.It reflects the green wavelength of light
C.It contains blue and yellow water
D.It is painted green by the plant
- 3.
How does water reach the leaves from the roots in tall trees?
A.It falls from the sky
B.It travels through the stem via xylem
C.It is absorbed through the leaf surface
D.It moves through the air
- 4.
What is generally considered the first step of photosynthesis?
A.Release of oxygen
B.Absorption of light energy by chlorophyll
C.Formation of starch
D.Absorption of water by roots
- 5.
In the chemical process of photosynthesis illustrated in the flowchart below, which specific raw material provides the carbon atoms necessary to synthesize the glucose () molecule?
A.Carbon Dioxide
B.Water
C.Chlorophyll
D.Solar Energy
- 6.
Which of the following statements about photosynthesis is correct?
A.It is a process where chemical energy is converted to light energy
B.It occurs in all living cells of a plant including roots
C.It is the process of converting inorganic raw materials into organic food
D.It takes place faster at night than during the day
- 7.
A plant is kept in a dark cupboard for three days. What will be the state of its leaves when tested with iodine?
A.The leaves will turn blue-black immediately
B.The leaves will show no change in color (remain brown)
C.The leaves will turn bright green
D.The leaves will turn purple
- 8.
During the evening, if the rate of photosynthesis equals the rate of respiration, what is the net exchange of between the leaf and the air?
A.Net intake
B.Net release
C.Zero net exchange
D.The leaf releases only oxygen
- 9.
Which of these is the most accurate description of the energy conversion that occurs during the process of photosynthesis?
A.Chemical energy is converted into light energy
B.Radiant energy is converted into potential chemical energy
C.Thermal energy is converted into kinetic energy
D.Electrical energy is converted into chemical energy
- 10.
Why does a plant die if its phloem is removed in a ring around the stem (girdling), even if the xylem is intact?
A.The plant cannot absorb water from the soil
B.The leaves cannot get the minerals required for photosynthesis
C.Manufactured food cannot reach the roots, causing them to starve and die
D.Oxygen cannot reach the leaves for photosynthesis
Download the worksheet for Plant Life - Photosynthesis process to practice offline. It includes additional chapter-level practice questions.
Factors affecting Photosynthesis
SubtopicFactors affecting Photosynthesis under Plant Life for Grade 7 ICSE.
Preview questions (no answers)
- 1.
Which of the following is an example of an organism that depends on the products of photosynthesis?
A.Human
B.Lion
C.Rabbit
D.All of the above
- 2.
Where is the oxygen produced during photosynthesis released into?
A.Into the soil
B.Into the roots
C.Into the atmosphere
D.Into the stem
- 3.
In the balanced equation for photosynthesis, how many molecules of carbon dioxide are typically used to produce one molecule of glucose?
A.1
B.6
C.12
D.3
- 4.
What is the typical color of a leaf that is rich in chlorophyll?
A.Red
B.Yellow
C.Green
D.Blue
- 5.
Which of the following describes the effect of very high temperatures (above ) on the enzymes involved in photosynthesis?
A.They work faster to produce more food
B.They become more stable
C.They begin to denature (lose their shape and function)
D.They change their function to help the plant breathe
- 6.
How does the hydration of the protoplasm (water content of the cell) influence the photosynthetic rate?
A.It has no influence as water is only used in the roots
B.Increased hydration generally helps maintain the structure and function of photosynthetic enzymes
C.Dry protoplasm speeds up the reaction to save the plant
D.Excess water in the protoplasm always stops photosynthesis
- 7.
In which part of the chloroplast does the 'Dark Reaction' (light-independent reaction) of photosynthesis take place?
A.Grana
B.Thylakoid
C.Stroma
D.Outer Membrane
- 8.
What would be the effect of increasing the temperature from to on the rate of photosynthesis?
A.The rate would double
B.The rate would increase slightly
C.The rate would drop to zero due to enzyme denaturation
D.The rate would stay the same because the plant is already at maximum capacity
- 9.
A plant is placed in a bell jar with a burning candle. After some time, the candle goes out. Then, the plant is exposed to light. Why can a new candle be lit and burn for longer in the jar afterwards?
A.The plant has absorbed all the heat from the first candle
B.The plant has replenished the oxygen supply via photosynthesis
C.The plant has removed the nitrogen from the air
D.The plant has produced more wax for the candle
- 10.
Which of the following colors of the visible spectrum is least effective for photosynthesis in most green plants?
A.Red
B.Blue
C.Green
D.Violet
Download the worksheet for Plant Life - Factors affecting Photosynthesis to practice offline. It includes additional chapter-level practice questions.
Respiration in Plants
SubtopicRespiration in Plants under Plant Life for Grade 7 ICSE.
Preview questions (no answers)
- 1.
In respiration, the energy stored in the chemical bonds of glucose is released as:
A.Chemical energy (ATP) and Heat
B.Light energy
C.Magnetic energy
D.Only potential energy
- 2.
If we use a delivery tube to pass the gas released by germinating seeds into lime water, the lime water turns:
A.Blue
B.Milky
C.Pink
D.Clear
- 3.
Comparing the two processes, respiration occurs in ______ cells and photosynthesis occurs in ______ cells.
A.All, green
B.Green, all
C.Dead, living
D.Animal, plant
- 4.
What is the primary role of enzymes in respiration?
A.To give green color to plants
B.To act as catalysts for chemical reactions
C.To absorb sunlight
D.To transport water
- 5.
In which part of the plant cell does the process of fermentation (anaerobic respiration) take place?
A.Only in the mitochondria
B.Only in the chloroplast
C.In the cytoplasm
D.Inside the nucleus
- 6.
During cellular respiration, the 'fuel' being oxidized is typically:
A.Water
B.Carbon dioxide
C.Glucose
D.Oxygen
- 7.
Which of the following describes the role of enzymes in plant respiration?
A.They are the main source of energy
B.They act as biological catalysts to speed up the breakdown of glucose
C.They provide the carbon dioxide for the reaction
D.They turn the plant green
- 8.
In the experiment to show is produced, if we use a Thermos flask, why do we plug the mouth with cotton wool instead of a tight rubber cork?
A.To allow the escape of heat so the thermometer doesn't break.
B.To allow some oxygen to enter for the seeds to continue respiring.
C.Cotton wool is a better insulator than rubber.
D.To prevent the seeds from being crushed by the pressure of the cork.
- 9.
Why does a plant die if its leaves are coated with a thick layer of petroleum jelly?
A.The jelly is poisonous and seeps into the phloem.
B.It blocks the stomata, preventing the exchange of gases for both respiration and photosynthesis.
C.It increases the rate of transpiration, leading to dehydration.
D.It prevents the leaf from absorbing sunlight, causing it to freeze.
- 10.
Which of the following chemical reactions represents the summary of what happens inside a plant cell during aerobic respiration?
A.B.C.D.
Download the worksheet for Plant Life - Respiration in Plants to practice offline. It includes additional chapter-level practice questions.
Comparison of Photosynthesis and Respiration
SubtopicComparison of Photosynthesis and Respiration under Plant Life for Grade 7 ICSE.
Preview questions (no answers)
- 1.
Which of the following molecules is NOT a reactant in the process of respiration?
A.Glucose
B.Oxygen
C.Chlorophyll
D.Enzymes
- 2.
Which cell organelle is known as the 'Powerhouse of the Cell' where respiration occurs?
A.Chloroplast
B.Mitochondrion
C.Nucleus
D.Vacuole
- 3.
If a plant is kept in a sealed glass jar in the dark, what gas will increase in concentration over time?
A.Oxygen
B.Carbon dioxide
C.Nitrogen
D.Water vapor
- 4.
What is the main difference between the timing of photosynthesis and respiration?
A.Photosynthesis is continuous, respiration is only at night
B.Respiration is continuous, photosynthesis is only in light
C.Both are only in light
D.Both are only at night
- 5.
The flowchart illustrates the relationship between two vital processes in a plant cell. If a condition occurs that specifically stops 'Process B' while 'Process A' continues to function in the light, which statement correctly describes the outcome for the plant?
A.The plant will stop producing glucose and will immediately lose all its stored food.
B.The plant will continue to synthesize glucose, but it will be unable to release the energy needed for growth and maintenance.
C.Oxygen levels within the plant will decrease rapidly because Process A requires oxygen to produce glucose.
D.Process A will automatically speed up to provide the cell with direct energy, bypassing the need for Process B.
- 6.
Which of the following describes the relationship between the two processes in the global carbon cycle?
A.They both increase carbon dioxide in the air
B.They both decrease oxygen in the air
C.Photosynthesis removes carbon dioxide while respiration adds it back
D.Respiration removes carbon dioxide while photosynthesis adds it back
- 7.
The oxygen required for respiration in plants is obtained through:
A.The xylem only
B.The roots only
C.Stomata and lenticels
D.The flower petals only
- 8.
If you were to graph the 'Net Oxygen Production' of a plant over 24 hours, where would the 'Compensation Points' be located?
A.At the highest point of the graph (Noon).
B.At the lowest point of the graph (Midnight).
C.At the points where the graph crosses the X-axis (zero net production).
D.The graph would never cross the X-axis because plants always produce .
- 9.
Which of these describes the 'Anabolic' nature of photosynthesis?
A.It breaks down large glucose molecules into smaller molecules.
B.It uses energy to build complex glucose molecules from simple and .
C.It releases energy in the form of ATP.
D.It is a spontaneous reaction that occurs without any input of energy.
- 10.
A leaf is placed in a test tube with a solution of Bromothymol Blue (a pH indicator that turns yellow in acidic -rich water). If the tube is kept in the light, the solution stays blue. If kept in the dark, it turns yellow. Why?
A.In the light, the produced by respiration is consumed by photosynthesis.
B.In the light, the plant produces an alkaline substance to neutralize the acid.
C.In the dark, the plant produces more , which is acidic.
D.The light itself changes the color of the chemical, not the plant.
Download the worksheet for Plant Life - Comparison of Photosynthesis and Respiration to practice offline. It includes additional chapter-level practice questions.