DAT BIOLOGY EXAM QUESTIONS AND
ANSWERS 2025/2026
1. If a cell's RNA is degraded, what immediate effect would this have on the
cell's function?
Protein synthesis would be impaired.
Cell division would occur more rapidly.
The cell would produce more lipids.
DNA replication would be halted.
2. Describe the significance of cholesterol in hormone synthesis.
Cholesterol is only involved in the synthesis of non-steroid
hormones.
Cholesterol serves as a precursor for steroid hormones, which
include aldosterone, cortisol, testosterone, and progesterone,
but not epinephrine.
Cholesterol is a byproduct of hormone synthesis.
Cholesterol is converted directly into epinephrine without any
intermediates.
3. Describe how linked genes affect inheritance patterns in organisms.
Linked genes can be separated by crossing over during meiosis.
Linked genes are always expressed together in the phenotype.
Linked genes assort independently during gamete formation.
Linked genes tend to be inherited together because they are
located on the same chromosome.
,4. A lake had a native population of a certain kind of fish. Over time, that
population diverged into many species. All the new fish species lived in
, the same lake, but ate different foods and occupied different habitats.
What type of speciation would have been involved in the changes to
the lake over a long period of time?
sympatric speciation
convergent
allopatric speciation
analogous
vicariance
5. Which of the following white blood cells are initially involved with the
inflammatory response?
Neutrophils and monocytes
Lymphocytes and plasma cells
Neutrophils and lymphocytes
Macrophages and lymphocytes
6. If a woman with an Rh- blood type has a first child who is Rh+, what
precautions should be taken during her subsequent pregnancies?
Monitor the baby's blood type closely after birth.
Encourage breastfeeding to improve the baby's immunity.
Administer Rh immunoglobulin to prevent sensitization.
Perform a blood transfusion before delivery.
7. Describe why plastids are considered an exception in the context of
animal cell structures.
Plastids are essential for cell division in animal cells.
Plastids are involved in energy production in animal cells.
, Plastids are primarily found in plant cells and are involved in
photosynthesis and storage, unlike animal cells.
Plastids are a type of vacuole found in animal cells.
8. The survival of some bacteria even in harsh and extreme environmental
conditions is facilitated by which structure?
Teichoic acid
Gram-negative membrane
Glycocalyx
Gram-positive membrane
Endospore
9. Describe the key difference between vascular plants that produce seeds
and those that do not.
All vascular plants produce seeds, but some do so in different
environments.
Vascular plants that do not produce seeds rely solely on
photosynthesis for reproduction.
Vascular plants that produce seeds have reproductive
structures that allow for seed formation, while those that do
not, like ferns, reproduce via spores.
Ferns and mosses are both vascular plants that produce seeds.
10. In a laboratory experiment, if the cortical reaction is inhibited in a
fertilized egg, what would be the expected outcome regarding
fertilization?
The egg will successfully develop into a normal embryo
Polyspermy may occur, leading to abnormal embryo
development
ANSWERS 2025/2026
1. If a cell's RNA is degraded, what immediate effect would this have on the
cell's function?
Protein synthesis would be impaired.
Cell division would occur more rapidly.
The cell would produce more lipids.
DNA replication would be halted.
2. Describe the significance of cholesterol in hormone synthesis.
Cholesterol is only involved in the synthesis of non-steroid
hormones.
Cholesterol serves as a precursor for steroid hormones, which
include aldosterone, cortisol, testosterone, and progesterone,
but not epinephrine.
Cholesterol is a byproduct of hormone synthesis.
Cholesterol is converted directly into epinephrine without any
intermediates.
3. Describe how linked genes affect inheritance patterns in organisms.
Linked genes can be separated by crossing over during meiosis.
Linked genes are always expressed together in the phenotype.
Linked genes assort independently during gamete formation.
Linked genes tend to be inherited together because they are
located on the same chromosome.
,4. A lake had a native population of a certain kind of fish. Over time, that
population diverged into many species. All the new fish species lived in
, the same lake, but ate different foods and occupied different habitats.
What type of speciation would have been involved in the changes to
the lake over a long period of time?
sympatric speciation
convergent
allopatric speciation
analogous
vicariance
5. Which of the following white blood cells are initially involved with the
inflammatory response?
Neutrophils and monocytes
Lymphocytes and plasma cells
Neutrophils and lymphocytes
Macrophages and lymphocytes
6. If a woman with an Rh- blood type has a first child who is Rh+, what
precautions should be taken during her subsequent pregnancies?
Monitor the baby's blood type closely after birth.
Encourage breastfeeding to improve the baby's immunity.
Administer Rh immunoglobulin to prevent sensitization.
Perform a blood transfusion before delivery.
7. Describe why plastids are considered an exception in the context of
animal cell structures.
Plastids are essential for cell division in animal cells.
Plastids are involved in energy production in animal cells.
, Plastids are primarily found in plant cells and are involved in
photosynthesis and storage, unlike animal cells.
Plastids are a type of vacuole found in animal cells.
8. The survival of some bacteria even in harsh and extreme environmental
conditions is facilitated by which structure?
Teichoic acid
Gram-negative membrane
Glycocalyx
Gram-positive membrane
Endospore
9. Describe the key difference between vascular plants that produce seeds
and those that do not.
All vascular plants produce seeds, but some do so in different
environments.
Vascular plants that do not produce seeds rely solely on
photosynthesis for reproduction.
Vascular plants that produce seeds have reproductive
structures that allow for seed formation, while those that do
not, like ferns, reproduce via spores.
Ferns and mosses are both vascular plants that produce seeds.
10. In a laboratory experiment, if the cortical reaction is inhibited in a
fertilized egg, what would be the expected outcome regarding
fertilization?
The egg will successfully develop into a normal embryo
Polyspermy may occur, leading to abnormal embryo
development
