FBISE Class 9th (SSC-l)

Explore subjects and practice MCQs

3
Chapters
1,610
Total MCQs

FBISE Class 9th (SSC-l)

1,610 MCQs Page 64 of 81
0
0
/ 1610
0%
A. Glucose
B. Starch
C. ATP
D. Protein
Answer: ATP supplies energy instantly because it can release energy quickly by breaking a phosphate bond.
A. Roots
B. Stomata
C. Xylem
D. Cuticle
Answer: CO2 diffuses into leaves through stomatal pores present on the leaf surface.
A. Proton gradient across the membrane
B. Direct splitting of glucose
C. Absorption of sunlight
D. Sodium pumping
Answer: The proton (H+) gradient built across the inner membrane drives ATP synthase to make ATP.
A. Oxygen
B. Carbon dioxide
C. Nitrogen
D. Hydrogen
Answer: Alcoholic fermentation in yeast releases carbon dioxide along with ethanol.
A. Photosynthetic enzymes are denatured
B. Light becomes weak
C. Carbon dioxide stops entering
D. Stomata close permanently
Answer: High temperature denatures the enzymes of photosynthesis, slowing the reactions even in bright light.
A. Ethanol
B. Lactic acid
C. Acetic acid
D. Citric acid
Answer: Anaerobic respiration in muscles produces lactic acid, which can cause fatigue and cramps.
A. Only at night
B. Only during the day
C. All the time
D. Only in winter
Answer: Respiration is a continuous process and occurs in plants day and night.
A. 1
B. 2
C. 4
Answer: Two ATP are used to phosphorylate glucose before the energy-yielding steps of glycolysis begin.
A. Kinetic energy
B. Chemical energy
C. Electrical energy
D. Mechanical energy
Answer: Light energy is trapped by chlorophyll and converted into chemical energy stored in glucose.
A. Only at night
B. In all cells of the plant
C. Only in light and in green parts
D. Only in roots
Answer: Photosynthesis requires light and chloroplasts, which are present in green parts of the plant.
A. Leaves
B. Roots
C. Flowers
D. Stems
Answer: Roots absorb water from the soil, which is transported to leaves for photosynthesis.
A. Oxidized
B. Reduced
C. Neutralized
D. Condensed
Answer: Glucose loses hydrogen and electrons during respiration, meaning it is oxidized.
A. Photosynthesis stops completely
B. Photosynthesis rate equals respiration rate
C. Respiration stops
D. Stomata close
Answer: At the compensation point the CO2 fixed by photosynthesis equals the CO2 released by respiration.
A. Carbon dioxide
B. Glucose
C. Water
D. Nitrate
Answer: Oxygen comes from the splitting of water during the light reaction, not from carbon dioxide.
A. Gain of electrons
B. Loss of electrons
C. Gain of hydrogen
D. Loss of oxygen
Answer: Oxidation is the loss of electrons, which may also involve loss of hydrogen or gain of oxygen.
A. Biological catalysts
B. Energy stores
C. Genetic material
D. Waste products
Answer: Enzymes are biological catalysts that speed up biochemical reactions without being used up.
A. Loss of electrons
B. Gain of electrons
C. Loss of hydrogen
D. Gain of oxygen
Answer: Reduction is the gain of electrons, which may also involve gain of hydrogen or loss of oxygen.
A. 1
B. 2
C. 3
D. 4
Answer: Each glucose produces two molecules of NADH when it is split into two pyruvate molecules.
A. Absorb
B. Release
C. Destroy
D. Store
Answer: Catabolic reactions break down molecules and release the energy stored in chemical bonds.
A. Reduced
B. Oxidized
C. Condensed
D. Neutralized
Answer: Water loses electrons and hydrogen during photolysis, so it is oxidized to release oxygen.