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1 : Which part of the Venus fly trap responds to touch?
1
:
Glands
2
:
Lobes
3
:
Tentacles
4
:
Trichomes
2 : Which structure in sundew plants captures insects?
1
:
Hood
2
:
Root hairs
3
:
Dew-covered tentacles
4
:
Lobes
3 : If a plant has interveinal chlorosis, which nutrient may be deficient?
1
:
Copper
2
:
Iron
3
:
Sulfur
4
:
Phosphorus
4 : A plant is grown in soil poor in nitrogen. What symptom is most expected?
1
:
Dark green leaves
2
:
Stunted growth
3
:
Rapid flowering
4
:
Leaf curling
5 : Which statement is true for all insectivorous plants?
1
:
They are heterotrophic
2
:
They don't perform photosynthesis
3
:
They trap insects for energy
4
:
They are autotrophic but use insects for nutrients
6 : Which three nutrients are primarily used to build organic compounds?
1
:
N, K, P
2
:
Fe, Mn, Cu
3
:
C, H, O
4
:
Ca, Mg, S
7 : Which is the correct pair of micronutrient and its deficiency symptom?
1
:
Iron - stunted roots
2
:
Zinc - interveinal chlorosis
3
:
Manganese - leaf drop
4
:
Copper - reduced growth
8 : What is the function of calcium in plants?
1
:
ATP production
2
:
Sugar storage
3
:
Cell wall stability
4
:
Photosynthesis
9 : What type of plants trap and digest insects for nitrogen?
1
:
Autotrophs
2
:
Heterotrophs
3
:
Insectivorous
4
:
Chemotrophs
10 : What are macronutrients?
1
:
Needed in small amounts
2
:
Secondary minerals
3
:
Required in large amounts
4
:
Used for reproduction
11 : Which nutrient forms the central atom in a chlorophyll molecule?
1
:
Iron
2
:
Nitrogen
3
:
Magnesium
4
:
Calcium
12 : Where is palisade tissue found in a leaf?
1
:
Lower epidermis
2
:
Below upper epidermis
3
:
Near veins
4
:
Inside stomata
13 : What is the role of nitrogen in plants?
1
:
Root elongation
2
:
Photosynthesis
3
:
Protein synthesis
4
:
Lignin formation
14 : What happens to stomata at night?
1
:
They open widely
2
:
They close
3
:
They remain unchanged
4
:
They secrete wax
15 : Which cells contain chloroplasts and control stomatal movement?
1
:
Mesophyll cells
2
:
Guard cells
3
:
Root hairs
4
:
Trichomes
16 : Where are guard cells located?
1
:
Xylem vessels
2
:
Leaf cuticle
3
:
Around stomata
4
:
Inside phloem
17 : What is the function of stomata in plants?
1
:
Water conduction
2
:
Nutrient absorption
3
:
Gaseous exchange
4
:
Light reflection
18 : Which nutrient helps regulate water balance in plants?
1
:
Zinc
2
:
Calcium
3
:
Potassium
4
:
Molybdenum
19 : Why are guard cells called hydraulic valves?
1
:
They break water molecules
2
:
They transport glucose
3
:
They open/close using water pressure
4
:
They store ions
20 : How do plants prevent water loss during the night?
1
:
Increase respiration
2
:
Block xylem flow
3
:
Close stomata
4
:
Release K+ into soil
21 : In what condition would stomata likely remain closed during the day?
1
:
Humid morning
2
:
High CO2 levels
3
:
Dry, hot weather
4
:
During rain
22 : What would happen if guard cells lose water rapidly?
1
:
Stomata remain open
2
:
Photosynthesis increases
3
:
Stomata close
4
:
K+ influx increases
23 : Which mechanism enables efficient gas diffusion inside leaves?
1
:
Thick cuticle
2
:
Dense trichomes
3
:
Air spaces in spongy mesophyll
4
:
High sugar concentration
24 : How does palisade mesophyll assist photosynthesis?
1
:
Provides CO₂
2
:
Supports root growth
3
:
Maximizes light absorption
4
:
Opens stomata
25 : What triggers K+ uptake in guard cells?
1
:
Red light
2
:
Blue light
3
:
Darkness
4
:
UV light
26 : Why is the starch-sugar hypothesis insufficient alone?
1
:
It ignores chloroplasts
2
:
It does not explain cell death
3
:
It fails to explain rapid turgor changes
4
:
It excludes role of K+
27 : How does the influx of K+ affect stomata?
1
:
Causes stomata to close
2
:
Reduces cell size
3
:
Increases osmotic pressure
4
:
Enhances chlorophyll breakdown
28 : Why does water enter guard cells during stomatal opening?
1
:
Increased CO₂ concentration
2
:
Active loss of starch
3
:
Decrease in osmotic potential
4
:
Passive light absorption
29 : Which issue would be affected first in wilted herbaceous plants?
1
:
Xylem
2
:
Parenchyma
3
:
Sclerenchyma
4
:
Phloem
30 : Why is lignin important in plants growing in windy areas?
1
:
Helps seed dispersal
2
:
Increases photosynthesis
3
:
Prevents water loss
4
:
Provides mechanical strength
31 : Which plant tissue is best suited for manufacturing ropes?
1
:
Parenchyma
2
:
Xylem
3
:
Collenchyma
4
:
Sclerenchyma
32 : How can knowledge of collenchyma help agriculture?
1
:
Prevents seed loss
2
:
Improves grain color
3
:
Enhances stem flexibility
4
:
Increases flower size
33 : What is the importance of turgor pressure in soft plant parts?
1
:
Absorbs light
2
:
Aids reproduction
3
:
Provides support
4
:
Helps in respiration
34 : How do xylem vessels support the plant body?
1
:
Conduct sugar
2
:
Produce starch
3
:
Transport water
4
:
Make leaves green
35 : Why are sclerenchyma cells mostly dead?
1
:
Thin cell wall
2
:
Lack of chloroplast
3
:
Fully lignified walls
4
:
No vacuoles
36 : Which feature differentiates sclereids from fibers?
1
:
Found in phloem
2
:
Contain chloroplasts
3
:
Smaller in size
4
:
Present in epidermis
37 : How do collenchyma support young plant parts?
1
:
Secondary wall thickening
2
:
Lignin deposition
3
:
Turgor pressure
4
:
Cell wall corner thickening
38 : A plant with delayed flowering and browning of leaves may lack:
1
:
Potassium
2
:
Phosphorus
3
:
Iron
4
:
Boron
39 : A plant shows weak stalks and yellow spots on old leaves. Which nutrient is likely deficient?
1
:
Sulfur
2
:
Magnesium
3
:
Calcium
4
:
Potassium
40 : Where are collenchyma cells usually located?
1
:
Root hairs
2
:
Leaf veins
3
:
Epidermis
4
:
Stem cortex
41 : Which of the following tissues lacks secondary cell walls?
1
:
Sclerenchyma
2
:
Xylem
3
:
Collenchyma
4
:
Phloem
42 : What compound is responsible for the rigidity of sclerenchyma walls?
1
:
Cellulose
2
:
Lignin
3
:
Pectin
4
:
Starch
43 : What happens if external pressure is applied to a solution?
1
:
Ψw decreases
2
:
Ψw increases
3
:
Ψw becomes zero
4
:
Ψw becomes undefined
44 : Which plant tissue helps in maintaining turgor pressure?
1
:
Sclerenchyma
2
:
Collenchyma
3
:
Parenchyma
4
:
Xylem
45 : How does Ψw influence root absorption of water?
1
:
Lower Ψw in roots draws water from soil
2
:
Higher Ψw in roots pushes water out
3
:
Ψw in roots is always constant
4
:
Ψw blocks water uptake
46 : Why is Ψw important for transpiration?
1
:
Helps gas exchange
2
:
Facilitates light absorption
3
:
Drives water upward
4
:
Reduces root uptake
47 : What does a steep water potential gradient indicate?
1
:
Slow water flow
2
:
Faster water flow
3
:
No water flow
4
:
Water moving upward only
48 : In which direction will water move in soil-plant-air continuum?
1
:
From air to soil
2
:
From root to soil
3
:
From high to low Ψw
4
:
From low to high Ψw
49 : What causes pressure potential to build up in plant cells?
1
:
Salt uptake
2
:
Water entry
3
:
Cell division
4
:
Loss of solutes
50 : Why does water move into plant cells by osmosis?
1
:
Lower Ψw inside cell
2
:
Higher Ψw inside cell
3
:
Equal Ψw on both sides
4
:
Random diffusion
51 : Which factor would increase Ψw in a plant cell?
1
:
Increase in solute
2
:
Decrease in ΨP
3
:
Entry of water
4
:
Loss of turgor
52 : How does pressure potential affect Ψw?
1
:
It always decreases Ψw
2
:
It stabilizes Ψw
3
:
It increases Ψw
4
:
It has no role
53 : Why does the addition of solutes lower water potential?
1
:
It increases pressure
2
:
It reduces kinetic energy of water
3
:
It makes Ψs more negative
4
:
It increases volume
54 : What is the value of solute potential (Ψs)?
1
:
Always positive
2
:
Always zero
3
:
Always negative
4
:
Varies randomly
55 : How does water move in terms of Ψw?
1
:
From low to high Ψw
2
:
From high to low Ψw
3
:
Randomly
4
:
Does not move
56 : What determines water potential in plant cells?
1
:
Only solute concentration
2
:
Only pressure
3
:
Solute and pressure potential
4
:
Turgor pressure only
57 : What is the value of water potential for pure water?
1
:
One
2
:
Zero
3
:
Negative
4
:
Infinite
58 : What is water potential symbolized by?
1
:
Ψs
2
:
ΨP
3
:
Ψw
4
:
Ψt
59 : What structural feature makes vessels efficient in water transport?
1
:
Thick walls
2
:
No protoplast
3
:
Perforation plates
4
:
Root hairs
60 : Why is the TACT mechanism considered passive?
1
:
It uses ATP
2
:
It needs carrier proteins
3
:
It depends on root pressure
4
:
It does not use energy directly
61 : In drought conditions, which xylem property helps water stay continuous?
1
:
Diffusion
2
:
Perforation
3
:
Adhesion and cohesion
4
:
Photosynthesis
62 : Why are xylem fibers important in trees?
1
:
They absorb nutrients
2
:
They allow gas exchange
3
:
They provide mechanical strength
4
:
They conduct food
63 : What happens if transpiration stops completely?
1
:
Water moves faster
2
:
Photosynthesis increases
3
:
Upward water flow stops
4
:
More minerals are absorbed
64 : What role do bordered pits play in tracheids?
1
:
Water storage
2
:
Lateral water movement
3
:
Blocking pathogens
4
:
Retaining minerals
65 : Which pathway bypasses both apoplast and symplast?
1
:
Root hair route
2
:
Endodermal flow
3
:
Vacuolar pathway
4
:
Capillary rise
66 : Why is the TACT mechanism important in tall plants?
1
:
Helps in root growth
2
:
Maintains water flow against gravity
3
:
Reduces transpiration
4
:
Increases photosynthesis
67 : Why do parenchyma cells become turgid?
1
:
Due to lignin
2
:
Water moves into vacuole
3
:
Elongation of cell wall
4
:
Thicker walls
68 : Why does the apoplast pathway stop at the endodermis?
1
:
Absence of water
2
:
Casparian strips block it
3
:
No xylem nearby
4
:
Cells die here
69 : Which pathway involves movement through cell walls?
1
:
Apoplast
2
:
Symplast
3
:
Vacuolar
4
:
Endodermal
70 : Which xylem element is dead and provides support?
1
:
Tracheid
2
:
Vessel
3
:
Xylem parenchyma
4
:
Xylem fiber
71 : What are plasmodesmata?
1
:
Xylem fibers
2
:
Cell wall thickenings
3
:
Cytoplasmic strands
4
:
Root hairs
72 : What is the main function of xylem in plants?
1
:
Photosynthesis
2
:
Transport of sugars
3
:
Water and mineral conduction
4
:
Nutrient storage
73 : Which part of the root absorbs most of the water and minerals?
1
:
Root cap
2
:
Root hairs
3
:
Root cortex
4
:
Endodermis
74 : Why is the pressure-flow theory important in agriculture?
1
:
Helps in irrigation systems
2
:
Improves nutrient absorption
3
:
Develops better fertilizers
4
:
Aids in crop yield improvement
75 : How does the sieve tube structure relate to function?
1
:
Thick walls provide strength
2
:
Sieve areas allow nutrient flow
3
:
Narrow structure stores sugars
4
:
Compact structure reduces water loss
76 : What happens if osmotic pressure differences are reduced?
1
:
Water will not move
2
:
Transpiration stops
3
:
Sugar transport is inefficient
4
:
Xylem transports sugars
77 : How does the pressure-flow theory assist in plant growth?
1
:
It explains water transport
2
:
It supports cellular functions with nutrients
3
:
It promotes photosynthesis
4
:
It helps nutrient storage
78 : What surrounds the vacuole and regulates ion transport in parenchyma?
1
:
Cell wall
2
:
Tonoplast
3
:
Cytoplasm
4
:
Plasma membrane
79 : What happens when sucrose is unloaded at the sink?
1
:
Osmotic pressure at the source increases
2
:
Water potential at the sink decreases
3
:
Water moves into xylem
4
:
Turgor pressure increases
80 : Why does water follow sucrose from source to sink?
1
:
Active transport
2
:
Osmosis due to osmotic pressure
3
:
Absorption from surrounding cells
4
:
By diffusion alone
81 : How does the pressure-flow theory explain sucrose movement?
1
:
Through diffusion
2
:
Osmotic pressure differences
3
:
Active transport of water
4
:
Transpiration pull
82 : Why does sucrose move from mesophyll to companion cells?
1
:
To reduce water potential
2
:
To increase sucrose in sieve tubes
3
:
To store sugars
4
:
To promote osmotic pressure
83 : What process moves water into sieve tubes at the source end?
1
:
Active transport
2
:
Diffusion
3
:
Osmosis
4
:
Evaporation
84 : Which component of phloem helps translocate sugars?
1
:
Tracheids
2
:
Sieve tube elements
3
:
Phloem fibres
4
:
Xylem parenchyma
85 : Which tissue in plants transports sucrose?
1
:
Xylem
2
:
Phloem
3
:
Cortex
4
:
Epidermis
86 : What is the role of companion cells in phloem?
1
:
Transport sugars
2
:
Supply ATP and proteins
3
:
Store sugars
4
:
Form sieve areas
87 : What is the primary function of phloem?
1
:
Transport of water
2
:
Transport of sugars
3
:
Transport of minerals
4
:
Transport of oxygen
88 : How does the use of auxins in cuttings affect plant propagation?
1
:
It promotes root growth and callus formation
2
:
It inhibits root growth and leaf formation
3
:
It induces leaf senescence
4
:
It provides bud initiation
89 : How can gibberellins be used to improve crop yields?
1
:
By promoting faster leaf senescence
2
:
By increasing cell division and elongation in fruits
3
:
By delaying fruit ripening
4
:
By inhibiting root growth
90 : How are cytokinins useful in plant tissue culture?
1
:
They inhibit cell division and root formation
2
:
They promote bud initiation and shoot growth
3
:
They delay leaf senescence
4
:
They break seed dormancy
91 : What application of abscisic acid is used in agriculture?
1
:
To promote flowering in long-day plants
2
:
To protect plants from drought stress
3
:
To increase the rate of seed germination
4
:
To promote leaf expansion
92 : How is ethylene used in the commercial production of fruit?
1
:
To prevent fruit ripening
2
:
To delay leaf senescence
3
:
To induce fruit ripening
4
:
To promote fruit growth
93 : How does gibberellin affect rosette plants?
1
:
It promotes bolting (flowering)
2
:
It inhibits seed germination
3
:
It causes leaf senescence
4
:
It reduces root growth
94 : Why does ethylene inhibit stem growth?
1
:
It increases the levels of cytokinins
2
:
It reduces cell division in stems
3
:
It promotes apical dominance
4
:
It stimulates cell elongation in stems
95 : Why does gibberellin promote flowering in long day plants?
1
:
It increases auxin production
2
:
It substitutes for red light, which is essential for flowering
3
:
It inhibits abscission in flowers
4
:
It reduces leaf senescence
96 : How does abscisic acid help during water stress?
1
:
Promotes leaf senescence
2
:
Closes stomata to conserve water
3
:
Stimulates fruit ripening
4
:
Promotes seed dormancy
97 : What is ethylene's main function in plants?
1
:
Promote root growth
2
:
Break seed dormancy
3
:
Stimulate fruit ripening
4
:
Delay bud initiation
98 : What does abscisic acid (ABA) mainly regulate in plants?
1
:
Promotes growth of roots and shoots
2
:
Inhibits stem and root growth during stress
3
:
Stimulates fruit ripening
4
:
Breaks seed dormancy
99 : What is the main role of gibberellins in plants?
1
:
Inhibit cell division
2
:
Promote cell enlargement and seed germination
3
:
Delay leaf senescence
4
:
Promote flowering in short-day plants
100 : Where are cytokinins primarily produced in plants?
1
:
In leaves and flowers
2
:
In roots, young fruits, and seeds
3
:
In stems and leaves
4
:
In roots and flower petals
101 : Which of the following is the primary function of auxins in plants?
1
:
Inhibit cell division
2
:
Promote cell enlargement and growth in roots
3
:
Stimulate leaf senescence
4
:
Promote seed dormancy
102 : Why is spring wood lighter?
1
:
Wider vessels
2
:
More water availability
3
:
Denser vessels
4
:
More xylem cells
103 : How is dendrochronology used in climate studies?
1
:
By measuring tree age
2
:
By analyzing wood growth
3
:
By comparing roots
4
:
By counting fruit
104 : What happens if vascular cambium is damaged?
1
:
No height growth
2
:
No leaf production
3
:
No thickness growth
4
:
Loss of bark protection
105 : Why study growth in plants for agriculture?
1
:
To control plant height
2
:
To increase flower production
3
:
To strengthen stems
4
:
To improve crop yield and quality
106 : How does cambium affect wood production?
1
:
Creates annual rings
2
:
Increases root growth
3
:
Forms more branches
4
:
Increases leaf size
107 : How does vascular cambium aid in growth?
1
:
By forming cork cells
2
:
By making phloem and xylem
3
:
By producing leaves
4
:
By increasing height
108 : Which meristem forms the bark?
1
:
Apical meristem
2
:
Cork cambium
3
:
Vascular cambium
4
:
Intercalary meristem
109 : Why do cells in elongation zone become large?
1
:
For cell differentiation
2
:
For cell division
3
:
For plant expansion
4
:
For sugar storage
110 : Why is secondary growth important in woody plants?
1
:
More vascular cambium
2
:
Less intercalary meristem
3
:
No lateral meristems
4
:
No apical meristems
111 : How do annual rings help in determining tree age?
1
:
By counting branches
2
:
By observing wood growth
3
:
By counting rings
4
:
By measuring roots
112 : How does cohesion help in water movement?
1
:
It prevents leakage
2
:
It binds with xylem walls
3
:
It forms an unbroken water column
4
:
It stops transpiration
113 : Where are intercalary meristems found?
1
:
Root tip
2
:
Between two vascular tissues
3
:
Base of internodes
4
:
Outer stem layer
114 : What is the function of lateral meristems?
1
:
Length growth
2
:
Thickness growth
3
:
Leaf production
4
:
Flower formation
115 : What causes primary growth in plants?
1
:
Apical meristem
2
:
Lateral meristem
3
:
Vascular cambium
4
:
Cork cambium
116 : What do salt glands in hydrophytes do?
1
:
Absorb water
2
:
Store nutrients
3
:
Excrete salts
4
:
Promote growth
117 : Why are mesophytes important?
1
:
They control salinity
2
:
They support food webs
3
:
They prevent soil erosion
4
:
They increase water levels
118 : How do halophytes tolerate salinity?
1
:
Absorb less salt
2
:
Excrete excess salts
3
:
Grow faster
4
:
Reduce salt in soil
119 : How do xerophytes prevent water loss?
1
:
Water storage in stems
2
:
Large leaves
3
:
Shallow roots
4
:
Leaf shedding
120 : How do hydrophytes expel excess water?
1
:
Through roots
2
:
Through hydathodes
3
:
Through leaves
4
:
Through flowers
121 : How does a hypertonic solution affect plant cells?
1
:
Cell swells
2
:
Causes plasmolysis
3
:
No effect
4
:
Cell divides
122 : Why do halophytes have succulent leaves?
1
:
To store nutrients
2
:
To store water
3
:
To store sugars
4
:
To store salt
123 : How do xerophytes minimize water loss?
1
:
Large leaves for transpiration
2
:
Waxy coatings, reduced leaves
3
:
Deep root systems
4
:
Water absorption through leaves
124 : Why do hydrophytes expel excess water?
1
:
To store more water
2
:
To avoid overhydration
3
:
To absorb nutrients
4
:
To store salts
125 : Why is the pressure-flow theory important in plant transport?
1
:
It explains water transport in xylem
2
:
It explains sugar transport to roots
3
:
It helps nutrient absorption
4
:
It explains nutrient storage
126 : What is a hypertonic solution?
1
:
Low solute concentration
2
:
Equal solute concentration
3
:
High solute concentration, water leaves
4
:
No movement of water
127 : Which environment do hydrophytes thrive in?
1
:
Dry conditions
2
:
Saline conditions
3
:
Aquatic environments
4
:
Moderate conditions
128 : What is a hypotonic solution?
1
:
High solute concentration
2
:
Equal solute concentration
3
:
Low solute concentration, water enters
4
:
No effect on the cell
129 : What is osmoregulation in plants?
1
:
Temperature regulation
2
:
Water and salt balance
3
:
Photosynthesis regulation
4
:
Respiratory control
130 : How does chemotropism benefit plants in nutrient-rich environments?
1
:
By guiding roots to grow towards high oxygen areas
2
:
By enabling roots to grow towards chemical nutrients like nitrogen
3
:
By preventing the loss of water
4
:
By facilitating flower pollination
131 : Why do plants in temperate regions produce heat-shock proteins?
1
:
To increase photosynthesis rates
2
:
To protect enzymes from high temperatures
3
:
To improve water uptake
4
:
To prevent leaf loss
132 : How does osmotic regulation help plants cope with drought stress?
1
:
By maintaining high sugar content in leaves
2
:
By absorbing excess water from the soil
3
:
By synthesizing heat-shock proteins
4
:
By increasing solute concentration in cells to retain water
133 : Why is thigmotropism important for climbing plants like vines?
1
:
It allows them to grow towards light
2
:
It enables them to coil around supports for stability
3
:
It helps them absorb more water
4
:
It accelerates root development
134 : How do heat-shock proteins help pigments in heat-stressed environments?
1
:
By reducing water loss
2
:
By enhancing protein folding and stability
3
:
By increasing cell division
4
:
By promoting flower growth
135 : How do plants avoid damage from freezing temperatures?
1
:
By accumulating sugar in the cells
2
:
By forming ice crystals in the cell wall but not inside the cell
3
:
By reducing water content
4
:
By increasing transpiration rates
136 : Why is gradual chilling less stressful for plants compared to rapid chilling?
1
:
It allows plants to adapt and adjust their membrane structure
2
:
It promotes faster nutrient uptake
3
:
It prevents ice crystals from forming
4
:
It helps plants grow faster
137 : How do plants respond to cold stress?
1
:
By forming ice crystals within cells
2
:
By increasing the proportion of unsaturated fatty acids in the membrane
3
:
By synthesizing heat-shock proteins
4
:
By decreasing the number of stomata
138 : Why do plants synthesize heat-shock proteins during heat stress?
1
:
To increase the rate of photosynthesis
2
:
To prevent enzyme denaturation
3
:
To promote seed formation
4
:
To enhance nutrient absorption
139 : What is geotropism in plants?
1
:
Movement of plants in response to touch
2
:
Movement of plants in response to gravity
3
:
Movement of plants towards light
4
:
Growth towards chemicals
140 : What is phototropism in plants?
1
:
Movement in response to water
2
:
Movement towards light
3
:
Movement in response to touch
4
:
Movement in response to gravity
141 : What is the effect of low temperature on plant cell membranes?
1
:
Membranes become more flexible
2
:
Membranes freeze and break
3
:
Membranes become rigid due to crystalline structure
4
:
Membranes become impermeable to water
142 : How do plants cope with high temperatures?
1
:
By synthesizing heat-shock proteins
2
:
By increasing transpiration
3
:
By closing stomata
4
:
By expanding their leaves
143 : What is thermoregulation in plants?
1
:
Maintaining body temperature through water absorption
2
:
Maintaining body temperature despite environmental changes
3
:
Cooling the plant using sunlight
4
:
Increasing temperature to speed up growth
144 : Which pigment absorbs red light at 660 nm?
1
:
Chlorophyll
2
:
P660
3
:
P730
4
:
Xanthophyll
145 : Why is florigen important for flowering?
1
:
Inhibits root growth
2
:
Induces flowering
3
:
Stops photosynthesis
4
:
Initiates dormancy
146 : In which condition will henbane flower?
1
:
Long night
2
:
Interrupted night
3
:
Short night
4
:
No dark period
147 : Which plant flowers regardless of photoperiod?
1
:
Cucumber
2
:
Chrysanthemum
3
:
Wheat
4
:
Tomato
148 : Which of the following is a short-day plant?
1
:
Tomato
2
:
Henbane
3
:
Tobacco
4
:
Chrysanthemum
149 : What would likely happen if a short-day plant is exposed to red light during night?
1
:
It will flower early
2
:
It will not flower
3
:
No effect
4
:
Increases leaf growth
150 : Why is P730 considered a time regulator?
1
:
Converts into light energy
2
:
Controls oxygen release
3
:
Signals flowering condition
4
:
Converts florigen into sugar
151 : What controls the time measurement for flowering?
1
:
Florigen only
2
:
Phytochrome alone
3
:
Hormones and dark period
4
:
Water and nutrients
152 : How do long-day plants respond to night interruption?
1
:
No effect
2
:
Delay flowering
3
:
Promote flowering
4
:
Cause leaf fall
153 : Why does interrupting long night with light prevent flowering in SDPs?
1
:
Light increases P660
2
:
Darkness stops hormones
3
:
Light halts florigen transport
4
:
Red light converts P730
154 : What happens to P660 in daylight?
1
:
Converts to sugar
2
:
Becomes inactive
3
:
Converts to P730
4
:
Triggers cell division
155 : What pigment detects light changes in plants?
1
:
Auxin
2
:
Phytochrome
3
:
Florigen
4
:
Chlorophyll
156 : What triggers flowering in short-day plants?
1
:
Long day
2
:
Long nights
3
:
High temperature
4
:
Rainfall
157 : Who first studied photoperiodism?
1
:
Mendel and Darwin
2
:
Watson and Crick
3
:
Garner and Allard
4
:
Hooker and Allard
158 : What is photoperiodism in plants?
1
:
Growth due to water
2
:
Movement toward light
3
:
Response to temperature
4
:
Response to day/night length
159 : What results from secondary growth?
1
:
Length increase
2
:
Thickness increase
3
:
Leaf size increase
4
:
Root number increase
160 : What are mesophytes?
1
:
Plants for dry conditions
2
:
Plants for saline environments
3
:
Plants for moderate environments
4
:
Plants for aquatic environments
Chapter 8 : Plant Physiology
Biology 11th MCQs || Ilam Ghar
Biology 11th
