Prepare with MCQs
Thousands of verified questions for competitive exams
25K+
MCQs
15+
Categories
500+
Tests
Free
Access
All
๐ General Knowledge
๐ Current Affairs
๐ต๐ฐ Pakistan Affairs
โช Islamic Studies
๐ค English
๐ป Computer
๐งฎ Mathematics
โ Physics
๐งช Chemistry
๐งฌ Biology
๐ฌ Everyday Science
๐ฉโ๐ซ Pedagogy
ุงุฑุฏู Urdu
๐บ World Geography
๐ History
Biology
Which component of blood is primarily responsible for clot formation?
A
Erythrocytes
B
Platelets
C
Lymphocytes
D
Plasma
Correct Answer
B
Biology
Which type of immunity develops after vaccination?
A
Artificial active immunity
B
Natural passive immunity
C
Artificial passive immunity
D
Innate immunity only
Correct Answer
A
Biology
Which cells are primarily responsible for producing antibodies?
A
T cells
B
Plasma cells
C
Neutrophils
D
Macrophages
Correct Answer
B
Biology
Which immunoglobulin is generally the first antibody produced during a primary immune response?
A
IgA
B
IgE
C
IgG
D
IgM
Correct Answer
D
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