1 What is the primary function of root hairs in plants? A To anchor the plant in the soil B To increase surface area for water and mineral absorption C To store excess food D To transport sugars to the leaves
2 Which pigment is the main photosynthetic pigment? A Chlorophyll-a B Chlorophyll-b C Carotenoid D Xanthophyll
3 Which process involves the movement of molecules from an area of higher concentration to lower concentration without using energy? A Active transport B Osmosis C Diffusion D Translocation
4 Which micronutrient is essential for the synthesis of chlorophyll in plants? A Iron B Magnesium C Nitrogen D Phosphorus
5 Which part of the ATP molecule stores the energy that is released when ATP is hydrolyzed to ADP? A The adenine ring B The ribose sugar C The bond between the second and third phosphate groups D The bond between adenine and ribose
7 What is the general chemical equation for photosynthesis? A 6CO2 + 6H2O → C6H12O6 + 6O2 B C6H12O6 + 6O2 → 6CO2 + 6H2O C 6CO2 + 6H2O → C6H12O6 + 6O2 + ATP D C6H12O6 → 2C3H4O3 + ATP
8 What is the first stage of aerobic respiration? A Krebs cycle B Glycolysis C Electron transport chain D Fermentation
9 What are the products of the light-dependent reactions of photosynthesis? A Glucose and oxygen B ATP and NADPH C Carbon dioxide and water D Pyruvic acid and ATP
10 Which of the following is a macronutrient required by plants? A Iron B Molybdenum C Calcium D Zinc
11 What are prosthetic groups? A Organic cofactors that are tightly bound to enzymes B Inorganic ions that are loosely attached C Protein subunits of enzymes D Substrates that bind to enzymes
12 Where do the light-independent reactions (Calvin cycle) take place? A Thylakoid membrane B Stroma C Cytoplasm D Mitochondrial matrix
13 How does a non-competitive inhibitor reduce enzyme activity? A It binds to the active site and blocks the substrate. B It binds to the enzyme at a site other than the active site, changing the shape of the active site. C It increases the temperature of the reaction. D It breaks down the substrate before the enzyme can act.
14 Which part of the chloroplast contains chlorophyll? A Stroma B Thylakoid membrane C Outer membrane D Intermembrane space
15 The loss of water vapor from the stomata is called: A Cuticular transpiration B Lenticular transpiration C Stomatal transpiration D Guttation
16 What is the effect of pH on enzyme activity? A Enzymes work best at any pH B Each enzyme has an optimum pH C pH has no effect on enzymes D Enzymes are permanently activated by extreme pH
17 Which model of enzyme action was proposed by Emil Fischer? A Induced fit model B Lock and key model C Fluid mosaic model D Saturation model
18 Which process describes the loss of water vapor from the aerial parts of a plant through stomata? A Respiration B Translocation C Transpiration D Guttation
19 What is the primary role of magnesium in plants? A It is a component of chlorophyll. B It regulates stomatal opening. C It strengthens cell walls. D It aids in protein synthesis.
22 Which of the following factors would increase the rate of transpiration? A High humidity B Low temperature C High wind speed D Closed stomata
23 What is the primary force responsible for the upward movement of water in the xylem? A Root pressure B Transpirational pull C Capillary action D Active transport
24 Which factor does NOT affect the rate of transpiration? A Temperature B Wind speed C Atmospheric humidity D Soil pH
25 Which of the following best describes the 'lock and key' model of enzyme action? A The enzyme changes shape to fit the substrate B The substrate changes shape to fit the enzyme C The active site of the enzyme is complementary to the substrate shape D Enzymes are rigid and do not interact with substrates