Q.1 What are stem cells?
Cells that can only do one job
Cells that can turn into many different types of cells
Cells that are already specialized
Cells that cannot divide
Explanation - Stem cells are undifferentiated cells capable of both self‑renewal and differentiation into various specialized cell types.
Correct answer is: Cells that can turn into many different types of cells
Q.2 Which of the following is an example of a stem cell?
Red blood cell
Neuronal cell
Embryonic stem cell
Epithelial cell
Explanation - Embryonic stem cells are derived from early embryos and can become almost any cell type.
Correct answer is: Embryonic stem cell
Q.3 Stem cells are best described as:
Cells that cannot divide
Specialized cells that repair tissues
Undifferentiated cells that can become many types
Dead cells that no longer function
Explanation - Undifferentiated means they have not yet specialized, giving them the ability to turn into many different kinds of cells.
Correct answer is: Undifferentiated cells that can become many types
Q.4 Which type of stem cell is found in bone marrow?
Embryonic stem cell
Adult stem cell
Stem cell factor
Stem cell niche
Explanation - Bone marrow contains adult (somatic) stem cells that help renew blood cells.
Correct answer is: Adult stem cell
Q.5 Stem cells can be used to help grow new:
Bones only
Muscles only
Tissues and organs
None of the above
Explanation - Stem cells can differentiate into many cell types, aiding the regeneration of tissues and organs.
Correct answer is: Tissues and organs
Q.6 What is a key difference between embryonic and adult stem cells?
Embryonic can become many types; adult are more limited
Adult can become many types; embryonic are limited
Both can become any cell type
Neither can divide
Explanation - Embryonic stem cells are pluripotent, while adult stem cells are multipotent with a narrower range.
Correct answer is: Embryonic can become many types; adult are more limited
Q.7 What does 'multipotent' mean?
Can become many cell types
Can become only one cell type
Can become a few different types
Cannot divide
Explanation - Multipotent cells can differentiate into several related cell types but not all.
Correct answer is: Can become a few different types
Q.8 Which organ is commonly used to harvest stem cells for research?
Heart
Liver
Bone marrow
Kidney
Explanation - Bone marrow is a primary source of adult stem cells, especially hematopoietic stem cells.
Correct answer is: Bone marrow
Q.9 Stem cells are important for:
Learning new languages
Regenerating damaged tissues
Cooking meals
Driving cars
Explanation - Their ability to renew and differentiate makes them key to tissue repair and regeneration.
Correct answer is: Regenerating damaged tissues
Q.10 What is a 'niche' in stem cell biology?
A type of stem cell
The place where stem cells live and are supported
A tool used to measure stem cell activity
A disease affecting stem cells
Explanation - Stem cell niches provide the microenvironment that regulates stem cell fate and maintenance.
Correct answer is: The place where stem cells live and are supported
Q.11 Which of these is NOT a function of stem cells?
Self-renewal
Differentiation
Cell death
Repair
Explanation - Stem cells mainly self-renew and differentiate; they are not primarily known for programmed cell death.
Correct answer is: Cell death
Q.12 Which organ system most directly uses stem cells for repair?
Digestive
Circulatory
Respiratory
Immune
Explanation - The immune system relies on hematopoietic stem cells in bone marrow to produce new immune cells.
Correct answer is: Immune
Q.13 Stem cells can be moved into a lab setting to grow new cells. This process is called:
Culturing
Recycling
Sequencing
Amplification
Explanation - Cell culture is the technique of growing cells outside their natural environment.
Correct answer is: Culturing
Q.14 Which type of stem cell therapy uses a patient's own cells?
Allogeneic
Autologous
Synthetic
None
Explanation - Autologous therapies use the patient's own stem cells, reducing rejection risk.
Correct answer is: Autologous
Q.15 The ability of stem cells to become many cell types is called:
Potency
Self-renewal
Differentiation
Migration
Explanation - Potency refers to the range of cell types a stem cell can produce.
Correct answer is: Potency
Q.16 Which of the following is a major ethical concern about embryonic stem cells?
They are too expensive
They are difficult to isolate
They involve destroying embryos
They are not useful
Explanation - Obtaining embryonic stem cells often requires destroying the embryo, raising ethical issues.
Correct answer is: They involve destroying embryos
Q.17 Which factor influences how stem cells differentiate?
Temperature only
Genetic signals and the environment
The color of the lab
The time of day
Explanation - External cues and intracellular signaling pathways guide stem cell fate decisions.
Correct answer is: Genetic signals and the environment
Q.18 Stem cells that can become any cell type are called:
Multipotent
Unipotent
Totipotent
Transdifferentiated
Explanation - Totipotent cells, such as early embryonic cells, can develop into an entire organism.
Correct answer is: Totipotent
Q.19 Which organ contains the most adult stem cells?
Brain
Skin
Bone marrow
Eye
Explanation - Bone marrow is rich in hematopoietic stem cells that replenish blood cells.
Correct answer is: Bone marrow
Q.20 What does 'self-renewal' mean in stem cells?
They can turn into any cell type
They can divide to produce more stem cells
They can change color
They can die quickly
Explanation - Self-renewal allows stem cells to maintain their population over time.
Correct answer is: They can divide to produce more stem cells
Q.21 In tissue engineering, what role does electrical stimulation play?
It kills cells
It encourages cells to grow and align
It has no effect
It makes cells move away
Explanation - Electric fields can influence cell behavior, promoting growth and directional organization.
Correct answer is: It encourages cells to grow and align
Q.22 Which type of stem cell is used in most cancer research?
Embryonic stem cell
Adult stem cell
Induced pluripotent stem cell
None of the above
Explanation - Induced pluripotent stem cells (iPSCs) are reprogrammed from adult cells and can mimic embryonic properties.
Correct answer is: Induced pluripotent stem cell
Q.23 What is the main difference between stem cells and specialized cells?
Stem cells can divide, specialized cells cannot
Specialized cells can divide, stem cells cannot
Stem cells can become many types; specialized cells are fixed
Specialized cells are always larger
Explanation - Stem cells retain the ability to differentiate, while specialized cells perform specific functions and are terminal.
Correct answer is: Stem cells can become many types; specialized cells are fixed
Q.24 Which of these is an example of a signaling molecule that influences stem cell fate?
Insulin
Glucose
Water
Oxygen
Explanation - Growth factors and hormones like insulin can direct stem cell differentiation.
Correct answer is: Insulin
Q.25 What does 'induced pluripotent stem cell' mean?
Stem cells that are naturally pluripotent
Adult cells reprogrammed to behave like embryonic stem cells
Stem cells that can only become one cell type
Stem cells that cannot divide
Explanation - iPSCs are created by reactivating embryonic genes in adult cells, giving them pluripotency.
Correct answer is: Adult cells reprogrammed to behave like embryonic stem cells
Q.26 Why are bone marrow stem cells important in medicine?
They help heal broken bones directly
They can be used to produce blood cells for transfusions
They replace all tissues in the body
They are not used medically
Explanation - Bone marrow transplants use hematopoietic stem cells to regenerate a patient's blood system.
Correct answer is: They can be used to produce blood cells for transfusions
Q.27 Which of the following best describes a 'multipotent' stem cell?
Can become any cell type in the body
Can become only one cell type
Can become a limited set of related cell types
Cannot divide
Explanation - Multipotent cells are restricted to a certain lineage, unlike pluripotent or totipotent cells.
Correct answer is: Can become a limited set of related cell types
Q.28 What is a common source of induced pluripotent stem cells (iPSCs) in research?
Skin fibroblasts
Red blood cells
Hair follicles
All of the above
Explanation - iPSCs can be generated from various adult cell types, including skin, blood, and hair.
Correct answer is: All of the above
Q.29 In tissue engineering, a scaffold is used for:
Providing mechanical support for cells to grow
Generating electric signals
Storing energy
Measuring temperature
Explanation - Scaffolds mimic the extracellular matrix, giving structure and guiding tissue formation.
Correct answer is: Providing mechanical support for cells to grow
Q.30 Which of these is a potential risk of stem cell therapy?
Tumor formation
Improved immunity
Increased hair growth
Decreased bone density
Explanation - Uncontrolled stem cell proliferation can lead to tumorigenesis if not properly regulated.
Correct answer is: Tumor formation
Q.31 Which organ is NOT a major site for adult stem cell activity?
Skin
Liver
Heart
Brain
Explanation - While some cardiac progenitors exist, the heart has very limited stem cell populations compared to skin, liver, or brain.
Correct answer is: Heart
Q.32 The process by which a stem cell becomes a specialized cell is called:
Transmutation
Differentiation
Duplication
Translocation
Explanation - Differentiation is the biological pathway leading a stem cell toward a specific cell lineage.
Correct answer is: Differentiation
Q.33 Which factor can enhance the differentiation of stem cells into bone cells?
High glucose
Vitamin D
Salt
Carbon dioxide
Explanation - Vitamin D promotes osteogenic differentiation, aiding bone formation.
Correct answer is: Vitamin D
Q.34 In stem cell research, the 'microenvironment' refers to:
The laboratory temperature
The surrounding cells and extracellular matrix
The computer used for analysis
The stem cell itself
Explanation - The microenvironment provides signals and support that influence stem cell behavior.
Correct answer is: The surrounding cells and extracellular matrix
Q.35 Which of the following is an example of an adult stem cell used for hair regrowth?
Hematopoietic stem cell
Neural stem cell
Hair follicle stem cell
Cardiac stem cell
Explanation - Hair follicle stem cells can regenerate hair and are studied for treating alopecia.
Correct answer is: Hair follicle stem cell
Q.36 What is a common method to assess stem cell potency?
Measuring cell size
Differentiation assays
Counting DNA strands
Testing for color changes
Explanation - Potency is evaluated by the ability of stem cells to differentiate into various cell types in assays.
Correct answer is: Differentiation assays
Q.37 Which of the following is a key difference between totipotent and pluripotent stem cells?
Totipotent cells can form any cell type including extraembryonic tissues; pluripotent cannot
Pluripotent cells can form all cell types; totipotent cannot
Both can form only one cell type
Totipotent cells are only found in adults
Explanation - Totipotent cells have the capacity to form an entire organism, whereas pluripotent cells cannot generate extraembryonic tissues.
Correct answer is: Totipotent cells can form any cell type including extraembryonic tissues; pluripotent cannot
Q.38 Electrical stimulation can influence stem cell differentiation by:
Increasing oxygen consumption
Altering gene expression patterns
Reducing cell adhesion
Increasing cell death rate
Explanation - Electrical cues can modify intracellular signaling cascades, affecting transcription factors that drive differentiation.
Correct answer is: Altering gene expression patterns
Q.39 Which of the following best describes an induced pluripotent stem cell (iPSC)?
A naturally occurring embryonic stem cell
A stem cell that has lost its multipotency
An adult cell reprogrammed to a pluripotent state
A stem cell that cannot differentiate
Explanation - iPSCs are generated by introducing key transcription factors into somatic cells, restoring embryonic-like potency.
Correct answer is: An adult cell reprogrammed to a pluripotent state
Q.40 Which signaling pathway is commonly involved in stem cell self-renewal?
Wnt/β-catenin
JAK/STAT
Notch
All of the above
Explanation - Wnt, JAK/STAT, and Notch pathways all play crucial roles in regulating stem cell proliferation and renewal.
Correct answer is: All of the above
Q.41 What is a potential application of stem cells in regenerative medicine?
Repair of spinal cord injuries
Enhancing athletic performance
Improving eyesight by creating new photoreceptors
All of the above
Explanation - Stem cells can be used to regenerate diverse tissues, including nervous system, muscle, and ocular tissues.
Correct answer is: All of the above
Q.42 Which type of scaffold material is most commonly used in bone tissue engineering?
Collagen
Hydroxyapatite
Polyethylene
Silicone
Explanation - Hydroxyapatite mimics bone mineral and supports osteogenic differentiation of stem cells.
Correct answer is: Hydroxyapatite
Q.43 What is the role of growth factors in stem cell differentiation?
They act as signals to activate differentiation pathways
They block all differentiation
They kill the stem cells
They serve no function
Explanation - Growth factors bind receptors and trigger intracellular cascades that direct stem cell fate.
Correct answer is: They act as signals to activate differentiation pathways
Q.44 Which of the following is a risk associated with stem cell transplantation?
Immune rejection
Infection
Tumor formation
All of the above
Explanation - Transplantation can elicit immune responses, infection risk, and potentially tumorigenic growth if not controlled.
Correct answer is: All of the above
Q.45 The term 'stem cell niche' refers to:
A special type of stem cell
A microenvironment that regulates stem cell behavior
The location where stem cells are stored in the lab
The area of a cell where DNA is located
Explanation - The niche provides signals, extracellular matrix, and cell-cell interactions essential for stem cell maintenance.
Correct answer is: A microenvironment that regulates stem cell behavior
Q.46 Which of the following best describes the term 'cellular senescence' in stem cells?
Permanent withdrawal from the cell cycle
Rapid division
Cell death
Migration to a new location
Explanation - Senescent cells cease proliferation and often secrete inflammatory factors.
Correct answer is: Permanent withdrawal from the cell cycle
Q.47 In stem cell research, what does 'in vitro' mean?
In living organisms
In a test tube or culture dish
In a living organism's body
In a computer simulation
Explanation - In vitro experiments are conducted outside of a living organism, typically in controlled laboratory settings.
Correct answer is: In a test tube or culture dish
Q.48 Which technique is commonly used to create induced pluripotent stem cells?
CRISPR gene editing
Retroviral transduction of Yamanaka factors
PCR amplification
Western blotting
Explanation - Introducing Oct4, Sox2, Klf4, and c-Myc via retroviruses reprograms somatic cells into iPSCs.
Correct answer is: Retroviral transduction of Yamanaka factors
Q.49 What is the primary function of the Wnt signaling pathway in stem cells?
Promote apoptosis
Maintain self-renewal and proliferation
Trigger differentiation into neurons
Inhibit cell cycle
Explanation - Wnt signaling activates β‑catenin, which promotes stem cell renewal and proliferation.
Correct answer is: Maintain self-renewal and proliferation
Q.50 Why are mesenchymal stem cells (MSCs) considered useful in regenerative therapies?
They can differentiate into bone, cartilage, and fat
They secrete immunomodulatory factors
They are easy to harvest from bone marrow
All of the above
Explanation - MSCs are versatile, can generate multiple lineages, and modulate immune responses.
Correct answer is: All of the above
Q.51 Which of the following best describes 'stem cell therapy'?
Using stem cells to replace damaged tissues
Using stem cells as a drug
Using stem cells to kill bacteria
None of the above
Explanation - Stem cell therapy aims to regenerate damaged or diseased tissues by introducing new cells.
Correct answer is: Using stem cells to replace damaged tissues
Q.52 Which of the following is NOT a characteristic of stem cells?
Self-renewal
Unlimited proliferation
Differentiation into specialized cells
Ability to remain undifferentiated
Explanation - Stem cells have limited proliferation potential; they cannot divide indefinitely without differentiation or exhaustion.
Correct answer is: Unlimited proliferation
Q.53 What is the main ethical concern regarding the use of embryonic stem cells?
High cost of treatment
Risk of tumor formation
Destruction of early embryos
Potential for overpopulation
Explanation - Obtaining embryonic stem cells often involves the destruction of a human embryo, raising ethical debates.
Correct answer is: Destruction of early embryos
Q.54 Which signaling pathway is key for maintaining stem cell pluripotency in culture?
PI3K/AKT
MAPK/ERK
TGF-β
All of the above
Explanation - PI3K/AKT, MAPK/ERK, and TGF-β pathways collectively regulate stem cell maintenance and pluripotency.
Correct answer is: All of the above
Q.55 In the context of tissue engineering, what role does electrical stimulation play when applied to stem cells?
It triggers apoptosis
It enhances cell proliferation and alignment
It changes the cell's DNA sequence
It reduces stem cell viability
Explanation - Electrical cues can influence stem cell behavior, promoting proliferation and directing cell orientation for tissue formation.
Correct answer is: It enhances cell proliferation and alignment
Q.56 Which of the following is a method used to evaluate the differentiation potential of stem cells?
Flow cytometry
Western blotting
Electrophoresis
All of the above
Explanation - Flow cytometry allows analysis of surface markers indicative of differentiation states in stem cells.
Correct answer is: Flow cytometry
Q.57 Which of the following best defines 'totipotency' in stem cells?
The capacity to give rise to all cell types, including extraembryonic tissues
The capacity to give rise to only one cell type
The ability to divide but not differentiate
The ability to become a tumor
Explanation - Totipotent cells, such as early zygotes, can generate an entire organism with both embryonic and extraembryonic tissues.
Correct answer is: The capacity to give rise to all cell types, including extraembryonic tissues
Q.58 Which of the following is a key advantage of using induced pluripotent stem cells (iPSCs) over embryonic stem cells?
iPSCs can be derived from adult tissues without ethical concerns
iPSCs can differentiate into any cell type
iPSCs are cheaper to produce
All of the above
Explanation - iPSCs circumvent the ethical issues associated with destroying embryos, while still offering pluripotency.
Correct answer is: iPSCs can be derived from adult tissues without ethical concerns
Q.59 Which of the following is NOT typically found in a stem cell niche?
Extracellular matrix proteins
Growth factors
Lipid bilayers
Immune cells
Explanation - While cell membranes contain lipid bilayers, the niche refers to the microenvironment surrounding stem cells, not the membrane itself.
Correct answer is: Lipid bilayers
Q.60 What is the primary role of the Notch signaling pathway in stem cell biology?
Promote differentiation into osteoblasts
Regulate cell fate decisions and maintain stemness
Induce apoptosis in stem cells
Enhance DNA repair mechanisms
Explanation - Notch signaling mediates cell-cell communication that influences stem cell maintenance and lineage specification.
Correct answer is: Regulate cell fate decisions and maintain stemness
Q.61 Which of the following is an example of a mechanical cue used in tissue engineering to influence stem cell differentiation?
Hydrostatic pressure
Chemical gradients
Electrical currents
Light exposure
Explanation - Mechanical stimuli such as pressure, shear stress, or stretch can direct stem cell fate toward specific lineages.
Correct answer is: Hydrostatic pressure
Q.62 Which type of stem cell is most commonly used in clinical trials for bone regeneration?
Embryonic stem cell
Neural stem cell
Mesenchymal stem cell
Hematopoietic stem cell
Explanation - Mesenchymal stem cells (MSCs) can differentiate into osteoblasts and are widely used for bone repair.
Correct answer is: Mesenchymal stem cell
Q.63 Which of the following best describes the role of growth factors in stem cell differentiation?
They serve as nutrients
They act as extracellular signals to initiate differentiation pathways
They block stem cell proliferation
They have no effect
Explanation - Growth factors bind receptors and trigger intracellular cascades that drive stem cell fate decisions.
Correct answer is: They act as extracellular signals to initiate differentiation pathways
Q.64 What does the term 'self-renewal' refer to in the context of stem cells?
The ability to differentiate into other cell types
The ability to undergo mitosis to produce identical stem cells
The ability to migrate to new locations
The ability to produce energy efficiently
Explanation - Self-renewal is the process by which stem cells divide to replenish their own population.
Correct answer is: The ability to undergo mitosis to produce identical stem cells
Q.65 Which signaling pathway is crucial for maintaining the pluripotency of embryonic stem cells?
Wnt/β-catenin
PI3K/AKT
JAK/STAT
All of the above
Explanation - Multiple pathways, including Wnt, PI3K/AKT, and JAK/STAT, cooperate to sustain embryonic stem cell pluripotency.
Correct answer is: All of the above
Q.66 Which type of scaffold material is often used in cardiac tissue engineering to support stem cell growth?
Chitosan
Polycaprolactone
Silicone rubber
All of the above
Explanation - Cardiac scaffolds can incorporate natural polymers like chitosan or synthetic ones such as polycaprolactone to guide stem cell differentiation.
Correct answer is: All of the above
Q.67 Which of the following is NOT a typical feature of adult stem cells?
Limited differentiation potential
High self-renewal capacity
Origin from embryonic development
Presence in specific tissues
Explanation - Adult stem cells arise during post-embryonic development and reside in tissues for maintenance and repair.
Correct answer is: Origin from embryonic development
Q.68 Which of the following best describes a 'unipotent' stem cell?
A stem cell that can differentiate into one specialized cell type
A stem cell that can differentiate into multiple types
A stem cell that can only self-renew
A stem cell that can differentiate into any cell type
Explanation - Unipotent stem cells can produce only a single cell lineage, but retain self-renewal ability.
Correct answer is: A stem cell that can differentiate into one specialized cell type
Q.69 In tissue engineering, which of the following techniques is used to apply electrical stimulation to stem cells?
Transcutaneous electrical nerve stimulation (TENS)
Electric field application in culture chambers
Magnetic resonance imaging (MRI)
Ultrasonic imaging
Explanation - Controlled electric fields in bioreactors can influence stem cell proliferation and differentiation.
Correct answer is: Electric field application in culture chambers
Q.70 Which of the following is a commonly used marker to identify mesenchymal stem cells?
CD34
CD90
CD45
CD4
Explanation - CD90 (Thy-1) is one of several cell surface markers used to isolate MSCs.
Correct answer is: CD90
Q.71 What is the primary mechanism by which stem cells can contribute to tissue regeneration?
They replace damaged cells by differentiation
They release anti-inflammatory cytokines only
They act solely as structural components
They become immune cells
Explanation - Stem cells differentiate into needed cell types, integrating into tissues and restoring function.
Correct answer is: They replace damaged cells by differentiation
Q.72 Which of the following best describes 'stem cell therapy' in the context of regenerative medicine?
Using stem cells to replace damaged tissues
Using stem cells to deliver drugs
Using stem cells to cause disease
Using stem cells to monitor patient health
Explanation - Stem cell therapy aims to regenerate or replace damaged or diseased tissues.
Correct answer is: Using stem cells to replace damaged tissues
Q.73 Which of the following is a key challenge in translating stem cell therapies to clinical practice?
Ensuring long-term safety and avoiding tumorigenesis
High costs of basic research
Lack of interest from clinicians
None of the above
Explanation - Safety concerns, particularly tumorigenic potential, are major hurdles before widespread clinical adoption.
Correct answer is: Ensuring long-term safety and avoiding tumorigenesis
Q.74 Which of the following best describes the role of electric fields in influencing stem cell behavior?
They have no effect on stem cells
They can direct stem cell migration and differentiation
They only affect cell membrane potential
They cause stem cells to die
Explanation - Electric fields can modulate intracellular signaling and cytoskeletal organization, guiding cell behavior.
Correct answer is: They can direct stem cell migration and differentiation
Q.75 In regenerative medicine, what does 'directed differentiation' refer to?
Allowing stem cells to differentiate randomly
Guiding stem cells to become a specific cell type using biochemical signals
Preventing stem cells from differentiating
Forcing stem cells to self-renew indefinitely
Explanation - Directed differentiation uses defined cues to steer stem cells toward desired lineages.
Correct answer is: Guiding stem cells to become a specific cell type using biochemical signals
Q.76 Which of the following signaling pathways is often targeted to promote osteogenic differentiation of stem cells?
Wnt/β-catenin
Notch
TGF-β/SMAD
All of the above
Explanation - Osteogenesis involves multiple pathways, including Wnt, Notch, and TGF-β/SMAD.
Correct answer is: All of the above
Q.77 What is a primary benefit of using induced pluripotent stem cells (iPSCs) over embryonic stem cells in personalized medicine?
They are ethically superior
They can be derived from a patient's own cells, reducing immune rejection
They are easier to culture
They have unlimited proliferation
Explanation - iPSCs derived from a patient’s somatic cells minimize rejection risks in autologous therapies.
Correct answer is: They can be derived from a patient's own cells, reducing immune rejection
Q.78 In the context of stem cell niche, which component is NOT typically involved in regulating stem cell fate?
Extracellular matrix components
Growth factor gradients
Cell–cell contact
Atmospheric pressure
Explanation - The niche relies on biochemical and biophysical signals, not atmospheric pressure, to influence stem cell behavior.
Correct answer is: Atmospheric pressure