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Branch 2 SPCB Actual Exam 2026-2027 BANK QUESTIONS
WITH DETAILED VERIFIED ANSWERS EXAM QUESTIONS
WILL COME FROM HERE (100% CORRECT ANSWERS A+
GRADED
1. Which of the following best describes the primary function of the
sodium-potassium (Na+/K+) ATPase pump?
A. Facilitated diffusion of sodium and potassium ions down their
concentration gradients
B. Active transport of sodium ions into the cell and potassium ions out
of the cell
C. Active transport of sodium ions out of the cell and potassium ions
into the cell
D. Passive cotransport of sodium and glucose into the cell
Answer: C
Explanation: The Na+/K+ ATPase pump is a primary active transporter
that uses the energy from ATP hydrolysis to move three sodium ions
out of the cell and two potassium ions into the cell against their
respective concentration gradients. This establishes the resting
membrane potential and maintains cellular osmotic balance.
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2. In Mendelian genetics, a dihybrid cross between two heterozygous
individuals (AaBb x AaBb) typically yields which phenotypic ratio in the
offspring, assuming independent assortment?
A. 3:1
B. 9:3:3:1
C. 1:2:1
D. 9:3:4
Answer: B
Explanation: The 9:3:3:1 ratio is characteristic of a dihybrid cross where
two genes assort independently. The ratio represents 9/16 offspring
having both dominant traits, 3/16 having the first dominant and second
recessive, 3/16 having the first recessive and second dominant, and
1/16 being doubly recessive.
3. What is the primary role of ribulose-1,5-bisphosphate carboxylase-
oxygenase (RuBisCO) in the Calvin cycle?
A. Regeneration of ribulose-1,5-bisphosphate
B. Reduction of 3-phosphoglycerate
C. Fixation of atmospheric carbon dioxide
D. Synthesis of glucose from glyceraldehyde-3-phosphate
Answer: C
Explanation: RuBisCO catalyzes the first major step of the Calvin cycle
by attaching carbon dioxide to ribulose-1,5-bisphosphate (RuBP), which
yields an unstable six-carbon intermediate that quickly splits into two
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molecules of 3-phosphoglycerate. This carbon fixation is the gateway
for inorganic carbon to enter the biosphere.
4. The Second Law of Thermodynamics states that for any spontaneous
process, the entropy of the universe:
A. Decreases
B. Remains constant
C. Increases
D. Becomes zero
Answer: C
Explanation: The Second Law of Thermodynamics asserts that the total
entropy of an isolated system, or the universe, always increases for a
spontaneous process. Entropy is a measure of disorder, and natural
processes tend to move toward greater disorder and dispersal of
energy.
5. Which type of chemical bond is characterized by the sharing of
electron pairs between atoms?
A. Ionic bond
B. Hydrogen bond
C. Covalent bond
D. Van der Waals interaction
Answer: C
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Explanation: A covalent bond is formed when two atoms share one or
more pairs of valence electrons to achieve a more stable electron
configuration. This contrasts with ionic bonds, which involve the
transfer of electrons, and intermolecular forces like hydrogen bonds
and van der Waals interactions.
6. In economics, the concept of "opportunity cost" refers to:
A. The total monetary expenditure on a good
B. The value of the next best alternative forgone
C. The cost incurred from inflation
D. The fixed cost of production
Answer: B
Explanation: Opportunity cost is a fundamental economic principle
representing the potential benefits an individual, investor, or business
misses out on when choosing one alternative over another. It includes
both explicit and implicit costs, not just monetary outlays.
7. Which organelle is primarily responsible for the synthesis of lipids
and detoxification of drugs?
A. Rough endoplasmic reticulum
B. Golgi apparatus
C. Smooth endoplasmic reticulum
D. Lysosome
Answer: C
Branch 2 SPCB Actual Exam 2026-2027 BANK QUESTIONS
WITH DETAILED VERIFIED ANSWERS EXAM QUESTIONS
WILL COME FROM HERE (100% CORRECT ANSWERS A+
GRADED
1. Which of the following best describes the primary function of the
sodium-potassium (Na+/K+) ATPase pump?
A. Facilitated diffusion of sodium and potassium ions down their
concentration gradients
B. Active transport of sodium ions into the cell and potassium ions out
of the cell
C. Active transport of sodium ions out of the cell and potassium ions
into the cell
D. Passive cotransport of sodium and glucose into the cell
Answer: C
Explanation: The Na+/K+ ATPase pump is a primary active transporter
that uses the energy from ATP hydrolysis to move three sodium ions
out of the cell and two potassium ions into the cell against their
respective concentration gradients. This establishes the resting
membrane potential and maintains cellular osmotic balance.
,2|Page
2. In Mendelian genetics, a dihybrid cross between two heterozygous
individuals (AaBb x AaBb) typically yields which phenotypic ratio in the
offspring, assuming independent assortment?
A. 3:1
B. 9:3:3:1
C. 1:2:1
D. 9:3:4
Answer: B
Explanation: The 9:3:3:1 ratio is characteristic of a dihybrid cross where
two genes assort independently. The ratio represents 9/16 offspring
having both dominant traits, 3/16 having the first dominant and second
recessive, 3/16 having the first recessive and second dominant, and
1/16 being doubly recessive.
3. What is the primary role of ribulose-1,5-bisphosphate carboxylase-
oxygenase (RuBisCO) in the Calvin cycle?
A. Regeneration of ribulose-1,5-bisphosphate
B. Reduction of 3-phosphoglycerate
C. Fixation of atmospheric carbon dioxide
D. Synthesis of glucose from glyceraldehyde-3-phosphate
Answer: C
Explanation: RuBisCO catalyzes the first major step of the Calvin cycle
by attaching carbon dioxide to ribulose-1,5-bisphosphate (RuBP), which
yields an unstable six-carbon intermediate that quickly splits into two
,3|Page
molecules of 3-phosphoglycerate. This carbon fixation is the gateway
for inorganic carbon to enter the biosphere.
4. The Second Law of Thermodynamics states that for any spontaneous
process, the entropy of the universe:
A. Decreases
B. Remains constant
C. Increases
D. Becomes zero
Answer: C
Explanation: The Second Law of Thermodynamics asserts that the total
entropy of an isolated system, or the universe, always increases for a
spontaneous process. Entropy is a measure of disorder, and natural
processes tend to move toward greater disorder and dispersal of
energy.
5. Which type of chemical bond is characterized by the sharing of
electron pairs between atoms?
A. Ionic bond
B. Hydrogen bond
C. Covalent bond
D. Van der Waals interaction
Answer: C
, 4|Page
Explanation: A covalent bond is formed when two atoms share one or
more pairs of valence electrons to achieve a more stable electron
configuration. This contrasts with ionic bonds, which involve the
transfer of electrons, and intermolecular forces like hydrogen bonds
and van der Waals interactions.
6. In economics, the concept of "opportunity cost" refers to:
A. The total monetary expenditure on a good
B. The value of the next best alternative forgone
C. The cost incurred from inflation
D. The fixed cost of production
Answer: B
Explanation: Opportunity cost is a fundamental economic principle
representing the potential benefits an individual, investor, or business
misses out on when choosing one alternative over another. It includes
both explicit and implicit costs, not just monetary outlays.
7. Which organelle is primarily responsible for the synthesis of lipids
and detoxification of drugs?
A. Rough endoplasmic reticulum
B. Golgi apparatus
C. Smooth endoplasmic reticulum
D. Lysosome
Answer: C
