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Biology
Which plant hormone is strongly associated with stomatal closure during water stress?
A
Auxin
B
Gibberellin
C
Abscisic acid
D
Cytokinin
Correct Answer
C
Biology
Which hormone promotes cell elongation and phototropic growth in plants?
A
Ethylene
B
Auxin
C
Abscisic acid
D
Cytokinin
Correct Answer
B
Biology
C4 plants have an advantage over C3 plants mainly because they:
A
Do not require sunlight
B
Reduce photorespiration under hot conditions
C
Do not perform photosynthesis
D
Lack chloroplasts
Correct Answer
B
Biology
Which enzyme catalyzes the fixation of carbon dioxide during the Calvin cycle?
A
ATP synthase
B
Rubisco
C
PEP carboxylase
D
Catalase
Correct Answer
B
Biology
The Calvin cycle occurs primarily in the:
A
Thylakoid membrane
B
Mitochondrial matrix
C
Chloroplast stroma
D
Cytoplasm
Correct Answer
C
Biology
Which photosynthetic pigment is directly involved in the reaction centers of photosystems?
A
Chlorophyll a
B
Chlorophyll b only
C
Carotene only
D
Xanthophyll
Correct Answer
A
Biology
Which property of phospholipids causes them to form a bilayer in water?
A
They are entirely hydrophobic
B
They are entirely hydrophilic
C
They are amphipathic
D
They contain only proteins
Correct Answer
C
Biology
Which molecule is the major structural component of the plasma membrane?
A
Phospholipid
B
Glycogen
C
Cellulose
D
Starch
Correct Answer
A
Biology
Which type of cell junction allows direct communication between adjacent animal cells?
A
Tight junction
B
Desmosome
C
Gap junction
D
Cell wall
Correct Answer
C
Biology
Which mechanism allows animal cells to engulf large particles?
A
Pinocytosis
B
Phagocytosis
C
Exocytosis
D
Osmosis
Correct Answer
B