Q.1 Which cellular organelle is responsible for producing the majority of ATP in a cell?
Ribosome
Nucleus
Mitochondria
Golgi apparatus
Explanation - Mitochondria are known as the powerhouses of the cell because they generate ATP through cellular respiration.
Correct answer is: Mitochondria
Q.2 In tissue engineering, what is the primary purpose of a scaffold?
To deliver growth factors
To provide a 3D structure for cell attachment
To replace damaged DNA
To generate electrical impulses
Explanation - Scaffolds mimic the extracellular matrix, giving cells a framework to attach, grow, and organize into functional tissues.
Correct answer is: To provide a 3D structure for cell attachment
Q.3 Which of the following tissues is primarily involved in hormone secretion?
Muscle tissue
Epithelial tissue
Neural tissue
Endocrine tissue
Explanation - Endocrine tissues secrete hormones directly into the bloodstream to regulate distant organs.
Correct answer is: Endocrine tissue
Q.4 Which cell type is commonly used as a starting material for engineering engineered cartilage?
Neuronal cells
Adipocytes
Chondrocytes
Osteoblasts
Explanation - Chondrocytes are the resident cells of cartilage and are often isolated or derived for cartilage tissue engineering.
Correct answer is: Chondrocytes
Q.5 What does the term 'biocompatible' mean when describing a material used in implants?
It is made from natural tissue
It can survive in water
It does not cause an adverse reaction in the body
It is biodegradable within a year
Explanation - Biocompatibility refers to a material's ability to perform its intended function without eliciting harmful immune responses.
Correct answer is: It does not cause an adverse reaction in the body
Q.6 Which of the following best describes an epithelial tissue’s primary function?
Contract and produce force
Conduct electrical signals
Line surfaces and protect underlying tissues
Store energy
Explanation - Epithelial tissues form protective barriers over body surfaces and cavities, and they can also secrete and absorb substances.
Correct answer is: Line surfaces and protect underlying tissues
Q.7 Which electrical property of a cell is described by the voltage across its plasma membrane at rest?
Action potential
Resting membrane potential
Synaptic potential
Conductance
Explanation - The resting membrane potential is the steady voltage across a cell’s membrane when it is not actively transmitting signals.
Correct answer is: Resting membrane potential
Q.8 What is the main component of the extracellular matrix that provides tensile strength to connective tissues?
Collagen
Elastin
Fibronectin
Glycosaminoglycans
Explanation - Collagen fibers give connective tissues (e.g., tendons, ligaments) their tensile strength and structural support.
Correct answer is: Collagen
Q.9 Which signaling molecule is most commonly used to induce stem cells to differentiate into bone cells?
Insulin-like growth factor
Bone morphogenetic protein (BMP)
Vascular endothelial growth factor (VEGF)
Fibroblast growth factor (FGF)
Explanation - BMPs are key osteogenic growth factors that promote differentiation of stem cells into osteoblasts, forming bone.
Correct answer is: Bone morphogenetic protein (BMP)
Q.10 Which type of muscle tissue is directly controlled by the nervous system for voluntary movements?
Cardiac muscle
Smooth muscle
Striated skeletal muscle
Myofibrillar muscle
Explanation - Striated skeletal muscle receives voluntary neural input, allowing conscious control of movements.
Correct answer is: Striated skeletal muscle
Q.11 Which property of a material is critical for enabling electrical stimulation of engineered cardiac tissue?
Hydrophilicity
Electrical conductivity
Porosity
Color
Explanation - Electrical conductivity allows the material to transmit signals that can synchronize heart muscle contractions in engineered tissues.
Correct answer is: Electrical conductivity
Q.12 What is the primary function of adipose (fat) tissue in the body?
Store and release energy
Transmit nerve impulses
Contract to produce movement
Produce blood cells
Explanation - Adipose tissue stores excess calories as triglycerides and releases fatty acids when the body needs energy.
Correct answer is: Store and release energy
Q.13 Which of the following best describes the role of growth factor release from a scaffold in tissue engineering?
To increase scaffold stiffness
To attract immune cells
To promote cell proliferation and differentiation
To decrease scaffold porosity
Explanation - Controlled release of growth factors from a scaffold can stimulate cells to grow, proliferate, and differentiate into target tissue types.
Correct answer is: To promote cell proliferation and differentiation
Q.14 Which of these tissues is characterized by the presence of a basement membrane?
Adipose tissue
Neural tissue
Epithelial tissue
Cartilage
Explanation - Basement membranes provide structural support and act as a barrier between epithelial layers and underlying connective tissue.
Correct answer is: Epithelial tissue
Q.15 The process by which a cell changes its phenotype to become another cell type is known as:
Metaplasia
Apoptosis
Differentiation
Proliferation
Explanation - Differentiation is the specialization of a cell, allowing it to acquire functions characteristic of a specific tissue type.
Correct answer is: Differentiation
Q.16 Which of the following cells is most important for repairing damaged neural tissue?
Neurons
Astrocytes
Microglia
Oligodendrocytes
Explanation - Astrocytes support neurons and participate in repair processes by releasing neurotrophic factors and modulating the inflammatory response.
Correct answer is: Astrocytes
Q.17 In the context of tissue engineering, what does 'in situ' refer to?
Engineering cells outside the body and then implanting them
Creating tissues in a bioreactor
Engineering tissues directly within the patient's body
Using synthetic polymers only
Explanation - In situ tissue engineering involves delivering cells and materials to a defect site so that tissue forms directly in the body.
Correct answer is: Engineering tissues directly within the patient's body
Q.18 Which type of tissue is primarily composed of cells that can produce and secrete neurotransmitters?
Cardiac tissue
Muscle tissue
Neural tissue
Epithelial tissue
Explanation - Neural tissue contains neurons that synthesize, store, and release neurotransmitters to communicate with other cells.
Correct answer is: Neural tissue
Q.19 Which component of the extracellular matrix is responsible for providing resistance to compression?
Collagen fibers
Elastin fibers
Proteoglycans
Fibronectin
Explanation - Proteoglycans attract water, creating a hydrated gel that resists compressive forces, especially in cartilage.
Correct answer is: Proteoglycans
Q.20 What is the primary source of energy for active transport across the plasma membrane?
Glucose
ATP
Oxygen
Carbon dioxide
Explanation - Active transport requires ATP to power pumps that move ions and molecules against their concentration gradients.
Correct answer is: ATP
Q.21 Which of the following best describes the function of a neural stem cell in regenerative medicine?
Produce bone matrix
Differentiate into nerve cells
Provide structural support
Create blood vessels
Explanation - Neural stem cells can give rise to neurons and glial cells, making them valuable for repairing nervous tissue damage.
Correct answer is: Differentiate into nerve cells
Q.22 Which property of a scaffold is critical for cell infiltration and nutrient diffusion?
High stiffness
Large pore size
Low porosity
High density
Explanation - Scaffold porosity and pore size allow cells to migrate in and ensure adequate nutrient and waste transport throughout the material.
Correct answer is: Large pore size
Q.23 The presence of what structural feature distinguishes skeletal muscle from smooth muscle?
Non-striated fibers
Presence of sarcomeres
Multinucleated cells
No pacemaker cells
Explanation - Skeletal muscle fibers contain organized sarcomeres, giving them a striped appearance and enabling voluntary contraction.
Correct answer is: Presence of sarcomeres
Q.24 Which of the following cells is responsible for forming the myelin sheath around peripheral nerve axons?
Schwann cells
Oligodendrocytes
Microglia
Astrocytes
Explanation - Schwann cells wrap around peripheral axons to form myelin, which increases the speed of electrical impulses.
Correct answer is: Schwann cells
Q.25 Which of the following is NOT a primary tissue type in the human body?
Epithelial
Connective
Muscle
Nuclear
Explanation - The four primary tissue types are epithelial, connective, muscle, and nervous. ‘Nuclear’ is not a tissue type.
Correct answer is: Nuclear
Q.26 What role do fibroblasts play in connective tissue?
Transmit nerve impulses
Produce extracellular matrix
Contract muscles
Form blood vessels
Explanation - Fibroblasts synthesize collagen, elastin, and proteoglycans that make up the extracellular matrix of connective tissues.
Correct answer is: Produce extracellular matrix
Q.27 Which electrical activity is characteristic of cardiac muscle cells during a heartbeat?
Action potentials with a plateau phase
Rapid oscillations without plateau
Slow depolarization only
No electrical activity
Explanation - Cardiac myocytes have a unique action potential that includes a prolonged plateau, essential for coordinated contraction.
Correct answer is: Action potentials with a plateau phase
Q.28 In tissue engineering, what is the advantage of using a biodegradable scaffold?
It never degrades
It provides permanent support
It allows gradual transfer of load to new tissue
It prevents cell adhesion
Explanation - Biodegradable scaffolds degrade over time, allowing the regenerated tissue to take over the mechanical load.
Correct answer is: It allows gradual transfer of load to new tissue
Q.29 Which of the following is a characteristic of stem cells used in tissue engineering?
Limited differentiation potential
Ability to self-renew indefinitely
No capacity for proliferation
Inability to respond to growth factors
Explanation - Stem cells can replicate themselves many times while retaining the potential to differentiate into specialized cell types.
Correct answer is: Ability to self-renew indefinitely
Q.30 What is the main difference between smooth and skeletal muscle regarding innervation?
Smooth muscle is voluntary, skeletal is involuntary
Smooth muscle receives autonomic innervation, skeletal receives somatic
Both receive autonomic innervation
Both receive somatic innervation
Explanation - Smooth muscle is controlled by the autonomic nervous system, whereas skeletal muscle is controlled by the somatic nervous system.
Correct answer is: Smooth muscle receives autonomic innervation, skeletal receives somatic
Q.31 Which of the following molecules acts as a key signaling component in the Wnt/β‑catenin pathway used in stem cell differentiation?
Insulin
Wnt protein
Glucagon
Epinephrine
Explanation - Wnt proteins bind to receptors to stabilize β‑catenin, which then promotes gene transcription for differentiation.
Correct answer is: Wnt protein
Q.32 Which property of an engineered tissue would be most important for a load‑bearing bone graft?
High electrical conductivity
High mechanical stiffness
High porosity for cell growth
Low surface roughness
Explanation - Load‑bearing bone must withstand mechanical forces, so a high stiffness matching native bone is critical.
Correct answer is: High mechanical stiffness
Q.33 Which of the following is a key feature of endothelial cells lining blood vessels?
Large nucleus
Production of collagen fibers
Regulation of vascular permeability
Contractile ability
Explanation - Endothelial cells control the movement of substances between the bloodstream and surrounding tissues.
Correct answer is: Regulation of vascular permeability
Q.34 What does the term 'osteogenic' refer to in tissue engineering?
Inducing bone formation
Inducing cartilage formation
Inducing muscle formation
Inducing nerve formation
Explanation - Osteogenic agents stimulate stem cells or progenitor cells to become bone-forming osteoblasts.
Correct answer is: Inducing bone formation
Q.35 Which of the following best describes the role of proteoglycans in cartilage?
Provide tensile strength
Store calcium ions
Resist compressive forces
Serve as structural support
Explanation - Proteoglycans attract water, creating a gel that compresses, thereby cushioning cartilage under load.
Correct answer is: Resist compressive forces
Q.36 Which of the following is a key advantage of using induced pluripotent stem cells (iPSCs) in tissue engineering?
Limited differentiation capacity
Reduced ethical concerns
Permanent immunogenicity
Inability to proliferate
Explanation - iPSCs are derived from adult cells, circumventing many ethical issues associated with embryonic stem cells.
Correct answer is: Reduced ethical concerns
Q.37 What does 'cellular apoptosis' refer to?
Cell division
Cell death through a controlled mechanism
Cell migration
Cell differentiation
Explanation - Apoptosis is a programmed, orderly process of cell death that prevents harmful effects on neighboring cells.
Correct answer is: Cell death through a controlled mechanism
Q.38 Which of these tissues is considered a 'non‑contractile' tissue type?
Muscle tissue
Neural tissue
Epithelial tissue
All of the above
Explanation - Epithelial tissue does not contract; it covers surfaces and secretes substances, unlike muscle or neural tissue.
Correct answer is: Epithelial tissue
Q.39 What is the main function of the basement membrane in epithelial tissues?
Signal to the immune system
Serve as a barrier and support structure
Conduct electrical impulses
Store nutrients
Explanation - The basement membrane anchors epithelial cells to underlying tissue and restricts unregulated cell migration.
Correct answer is: Serve as a barrier and support structure
Q.40 In tissue engineering, what does 'mechanotransduction' refer to?
Electrical stimulation of cells
Chemical signaling in tissues
Conversion of mechanical signals into biochemical responses
Cell migration due to chemical gradients
Explanation - Mechanotransduction involves cells translating physical forces into signals that influence behavior and differentiation.
Correct answer is: Conversion of mechanical signals into biochemical responses
Q.41 Which of the following is NOT a function of cartilage in the body?
Provide a smooth surface for joint movement
Store calcium ions
Serve as a shock absorber
Transmit signals between cells
Explanation - Cartilage primarily provides a smooth, low‑friction surface and cushions joints; it does not store calcium.
Correct answer is: Store calcium ions
Q.42 Which of the following proteins is most abundant in the cytoplasm of muscle cells?
Myosin
Collagen
Elastin
Actin
Explanation - Myosin is the motor protein that interacts with actin to produce muscle contraction.
Correct answer is: Myosin
Q.43 What is the main difference between a natural and a synthetic biomaterial used for scaffolds?
Natural materials are always biodegradable
Synthetic materials cannot be functionalized
Natural materials are derived from biological sources, synthetic from non‑living sources
Synthetic materials always have higher biocompatibility
Explanation - Natural biomaterials come from living organisms (e.g., collagen), whereas synthetic biomaterials are chemically manufactured.
Correct answer is: Natural materials are derived from biological sources, synthetic from non‑living sources
Q.44 Which cell type is primarily responsible for the production of the extracellular matrix in bone?
Osteoclasts
Chondrocytes
Osteoblasts
Fibroblasts
Explanation - Osteoblasts synthesize bone matrix proteins like collagen and initiate mineral deposition.
Correct answer is: Osteoblasts
Q.45 What does 'immunogenicity' refer to in the context of implanted biomaterials?
The ability to conduct electricity
The potential to cause an immune response
The mechanical strength of a material
The degradation rate of a material
Explanation - Immunogenicity describes how likely a material is to trigger the body’s immune system, affecting biocompatibility.
Correct answer is: The potential to cause an immune response
Q.46 Which of these is a hallmark of stem cell pluripotency?
Differentiation into only one cell type
Self‑renewal without differentiation
Ability to differentiate into multiple cell lineages
Resistance to all growth factors
Explanation - Pluripotent stem cells can become any of the three germ layers, allowing differentiation into many tissue types.
Correct answer is: Ability to differentiate into multiple cell lineages
Q.47 Which type of tissue is primarily responsible for the rapid transmission of electrical signals along the spinal cord?
Epithelial tissue
Connective tissue
Nervous tissue
Muscle tissue
Explanation - Nervous tissue, specifically neurons, conduct electrical impulses throughout the nervous system.
Correct answer is: Nervous tissue
Q.48 What is the significance of the 'plateau phase' in the cardiac action potential?
It increases the frequency of beats
It allows more Ca²⁺ influx, prolonging contraction
It reduces the time for repolarization
It is responsible for repolarization
Explanation - The plateau phase extends the action potential, permitting sustained Ca²⁺ entry and a longer contraction period.
Correct answer is: It allows more Ca²⁺ influx, prolonging contraction
Q.49 Which of the following is a common method to enhance cell adhesion to a synthetic scaffold?
Adding a fluorescent dye
Coating with fibronectin
Increasing scaffold density
Heating the scaffold
Explanation - Fibronectin is an extracellular matrix protein that promotes integrin-mediated cell attachment to biomaterials.
Correct answer is: Coating with fibronectin
Q.50 What is a primary function of the vascular system in engineered tissues?
Provide structural support
Store nutrients
Deliver oxygen and remove waste
Generate electrical signals
Explanation - Vascularization is crucial for supplying oxygen and nutrients, and for removing metabolic waste from engineered tissues.
Correct answer is: Deliver oxygen and remove waste
Q.51 Which of the following is an example of a natural polymer used as a scaffold material?
Polyethylene glycol
Collagen
Polylactic acid
Polyethylene
Explanation - Collagen is a naturally occurring protein in the extracellular matrix, widely used for biomaterial scaffolds.
Correct answer is: Collagen
Q.52 What does the term 'bioreactor' refer to in tissue engineering?
A device that provides mechanical and biochemical cues to developing tissues
A type of scaffold material
A natural tissue found in the body
An implantable electrical stimulator
Explanation - Bioreactors simulate physiological conditions to grow tissues in vitro before implantation.
Correct answer is: A device that provides mechanical and biochemical cues to developing tissues
Q.53 Which of the following best describes the role of integrins in cell‑matrix interactions?
They act as ion channels
They are enzymes that degrade ECM
They mediate cell adhesion to the extracellular matrix
They store calcium ions
Explanation - Integrins are transmembrane receptors that connect the cytoskeleton to the ECM, facilitating adhesion and signaling.
Correct answer is: They mediate cell adhesion to the extracellular matrix
Q.54 Which of the following is a typical outcome of applying cyclic mechanical stretch to cultured cardiac cells?
Inhibition of cell proliferation
Enhanced differentiation into myocytes
Reduction in cell viability
Loss of cell alignment
Explanation - Mechanical stretch can promote alignment and maturation of cardiac cells, improving contractile function.
Correct answer is: Enhanced differentiation into myocytes
Q.55 In the context of tissue engineering, what is the purpose of using a hydrogel?
To provide electrical conduction
To offer a hydrated, porous environment for cells
To increase scaffold stiffness
To serve as a source of nutrients
Explanation - Hydrogels retain water, mimic natural ECM, and support cell infiltration and nutrient diffusion.
Correct answer is: To offer a hydrated, porous environment for cells
Q.56 Which of the following best describes the 'Goldilocks principle' in scaffold design?
The scaffold must be too stiff for cells
The scaffold must be too flexible for cells
The scaffold must have moderate mechanical properties suitable for the target tissue
The scaffold must be non‑biocompatible
Explanation - The scaffold should mimic the natural mechanical environment of the target tissue – not too hard, not too soft.
Correct answer is: The scaffold must have moderate mechanical properties suitable for the target tissue
Q.57 What is the main reason for incorporating growth factors into a tissue engineering scaffold?
To increase mechanical strength
To enhance cell adhesion only
To direct cell proliferation and differentiation
To make the scaffold fluorescent
Explanation - Growth factors act as biochemical cues that guide stem or progenitor cells toward specific lineages.
Correct answer is: To direct cell proliferation and differentiation
Q.58 Which of the following is a key advantage of using 3D bioprinting for tissue engineering?
It reduces the need for cells
It allows precise placement of cells and materials in a layer‑by‑layer fashion
It eliminates the need for scaffolds
It is faster than all other methods
Explanation - 3D bioprinting can produce complex architectures by depositing cells and bioinks in specific spatial patterns.
Correct answer is: It allows precise placement of cells and materials in a layer‑by‑layer fashion
Q.59 What is a major challenge in vascularizing engineered tissue constructs?
Preventing electrical conduction
Maintaining scaffold shape
Establishing an efficient capillary network throughout the tissue
Reducing cell proliferation
Explanation - Without adequate vasculature, cells in the interior of a construct become hypoxic and die.
Correct answer is: Establishing an efficient capillary network throughout the tissue
Q.60 Which of the following statements best describes the action of matrix metalloproteinases (MMPs) in tissue engineering?
They provide structural support to scaffolds
They degrade extracellular matrix components to facilitate cell migration
They produce growth factors
They increase scaffold stiffness
Explanation - MMPs remodel the ECM by breaking down proteins, enabling cells to move and remodel their environment.
Correct answer is: They degrade extracellular matrix components to facilitate cell migration
Q.61 Which of the following best illustrates the concept of a 'bioactive' surface?
A surface that remains inert in body fluids
A surface that actively releases antibiotics
A surface that promotes specific cellular responses such as adhesion or differentiation
A surface with high electrical resistance
Explanation - Bioactive surfaces interact with biological molecules or cells to elicit desired responses.
Correct answer is: A surface that promotes specific cellular responses such as adhesion or differentiation
Q.62 What role does the 'basement membrane' play in epithelial tissues?
It stores energy
It provides a structural scaffold and regulates cell behavior
It transmits electrical impulses
It is responsible for muscle contraction
Explanation - The basement membrane anchors epithelial cells and influences their proliferation, differentiation, and polarity.
Correct answer is: It provides a structural scaffold and regulates cell behavior
Q.63 Which of the following is NOT typically a function of connective tissue?
Support and protect organs
Transport nutrients
Generate force via contraction
Store fat
Explanation - Connective tissue supports, binds, and stores, but does not contract to produce force.
Correct answer is: Generate force via contraction
Q.64 Which cell type is known for its ability to form a blood clot by releasing clotting factors?
Platelets
Red blood cells
White blood cells
Erythroblasts
Explanation - Platelets are involved in hemostasis, releasing factors that initiate the clotting cascade.
Correct answer is: Platelets
Q.65 In the process of tissue engineering, what is a 'seed cell'?
A cell that produces scaffold material
A cell that initiates tissue formation within a scaffold
A cell that degrades the scaffold
A cell that becomes immune to the scaffold
Explanation - Seed cells are seeded into a scaffold to populate it and drive new tissue formation.
Correct answer is: A cell that initiates tissue formation within a scaffold
Q.66 Which of the following best describes the 'platelet‑derived growth factor (PDGF)'?
A hormone that regulates blood pressure
A cytokine that promotes cell proliferation and migration
An enzyme that degrades ECM
A structural protein of collagen
Explanation - PDGF stimulates proliferation of mesenchymal cells and is used in tissue repair strategies.
Correct answer is: A cytokine that promotes cell proliferation and migration
Q.67 What is the primary reason for using 'dynamic' (as opposed to static) culture conditions in bioreactors?
To increase scaffold degradation
To provide mechanical stimulation and improved nutrient distribution
To reduce cell adhesion
To eliminate the need for growth factors
Explanation - Dynamic conditions mimic physiological forces and enhance mass transport, promoting better cell growth.
Correct answer is: To provide mechanical stimulation and improved nutrient distribution
Q.68 Which of the following is a hallmark of bone tissue’s mechanical property?
High tensile strength
High compressive strength
Low compressive strength
Low electrical conductivity
Explanation - Bone is exceptionally strong in compression, allowing it to bear loads and protect organs.
Correct answer is: High compressive strength
Q.69 Which of these is a function of the myelin sheath?
Providing structural support to muscles
Increasing the speed of nerve impulse conduction
Storing genetic information
Transporting oxygen in blood
Explanation - Myelin insulates axons, enabling rapid transmission of electrical signals.
Correct answer is: Increasing the speed of nerve impulse conduction
Q.70 What does 'osteoclast' refer to?
A cell that forms bone
A cell that resorbs bone
A cell that produces cartilage
A type of stem cell
Explanation - Osteoclasts break down bone tissue during remodeling and calcium mobilization.
Correct answer is: A cell that resorbs bone
Q.71 Which of the following is a primary advantage of using decellularized extracellular matrix as a scaffold?
It is highly immunogenic
It retains natural biochemical cues and architecture
It cannot be sterilized
It is purely synthetic
Explanation - Decellularized ECM maintains the native tissue's composition, promoting cell adhesion and differentiation.
Correct answer is: It retains natural biochemical cues and architecture
Q.72 Which of the following best describes the 'myogenic differentiation' process?
Formation of cartilage from fibroblasts
Formation of muscle cells from stem cells
Formation of nerve cells from mesenchymal stem cells
Formation of blood cells from hematopoietic stem cells
Explanation - Myogenic differentiation refers to stem cells acquiring a muscle cell phenotype.
Correct answer is: Formation of muscle cells from stem cells
Q.73 What is the purpose of 'co-culture' in tissue engineering?
To grow only one cell type
To culture cells under anaerobic conditions
To grow two or more cell types together to mimic tissue interactions
To increase scaffold porosity
Explanation - Co-culture enables communication between different cell types, improving tissue development.
Correct answer is: To grow two or more cell types together to mimic tissue interactions
Q.74 Which of the following is a key challenge when engineering large tissue constructs?
Rapid cell division
Adequate nutrient diffusion
Excessive scaffold stiffness
High electrical resistance
Explanation - Large constructs suffer from diffusion limits, leading to central necrosis without vascularization.
Correct answer is: Adequate nutrient diffusion
Q.75 Which of these molecules is a major component of the endoplasmic reticulum’s function in protein synthesis?
Mitochondria
Ribosomes
Chloroplasts
Nucleus
Explanation - Ribosomes on the ER synthesize proteins that are either secreted, embedded in membranes, or sent to the Golgi.
Correct answer is: Ribosomes
Q.76 What role do fibroblasts play in skin regeneration?
They produce keratin
They secrete collagen to rebuild the dermis
They generate sweat
They form hair follicles
Explanation - Fibroblasts are the main producers of collagen and other ECM proteins during skin repair.
Correct answer is: They secrete collagen to rebuild the dermis
Q.77 Which of the following statements correctly describes a 'regenerative scaffold'?
It is purely decorative
It promotes cell growth and differentiation by mimicking natural tissue properties
It prevents any cell attachment
It is a type of electrode
Explanation - Regenerative scaffolds provide a template that supports cell adhesion, growth, and tissue formation.
Correct answer is: It promotes cell growth and differentiation by mimicking natural tissue properties
Q.78 Which of the following best describes the role of oxygen tension in stem cell culture?
It has no effect on differentiation
Low oxygen can enhance stem cell proliferation and maintenance
High oxygen always promotes differentiation
Oxygen tension is irrelevant
Explanation - Hypoxic conditions often preserve stemness and can influence lineage commitment.
Correct answer is: Low oxygen can enhance stem cell proliferation and maintenance
Q.79 What is the primary function of the Golgi apparatus in a cell?
Produce ATP
Package and modify proteins for secretion or delivery within the cell
Store genetic information
Control cell division
Explanation - The Golgi modifies, sorts, and packages proteins for transport to various cellular destinations.
Correct answer is: Package and modify proteins for secretion or delivery within the cell
Q.80 Which of the following is a key property of a 'hydrogel' scaffold used in cartilage tissue engineering?
Low water content
High electrical conductivity
High water content and viscoelasticity
Rigid, non‑porous structure
Explanation - Hydrogels can swell with water and mimic the lubricating environment of cartilage.
Correct answer is: High water content and viscoelasticity
Q.81 Which cell type is responsible for the production of the 'basement membrane' in tissues?
Epithelial cells
Fibroblasts
Myocytes
Osteoclasts
Explanation - Epithelial cells secrete basement membrane components that support tissue architecture.
Correct answer is: Epithelial cells
Q.82 In a tissue‑engineered bone construct, which cell type is crucial for mineral deposition?
Osteoclasts
Chondrocytes
Osteoblasts
Adipocytes
Explanation - Osteoblasts synthesize bone matrix proteins and initiate mineralization.
Correct answer is: Osteoblasts
Q.83 Which of the following is a characteristic of 'stem cell plasticity'?
Inability to change phenotype
Ability to differentiate into multiple cell types under appropriate cues
Only ability to divide without differentiation
Strict lineage restriction
Explanation - Stem cell plasticity allows them to respond to environmental signals and adopt different fates.
Correct answer is: Ability to differentiate into multiple cell types under appropriate cues
Q.84 What is the main difference between 'autograft' and 'allograft' in tissue transplantation?
Autografts come from a different species
Allografts come from the same individual
Autografts come from the same individual; allografts from another individual of the same species
Allografts are synthetic
Explanation - An autograft uses the patient's own tissue, reducing rejection risk; an allograft comes from another person.
Correct answer is: Autografts come from the same individual; allografts from another individual of the same species
Q.85 Which of these processes is essential for the development of a functional vascular network in a tissue‑engineered construct?
Inhibition of angiogenesis
Promotion of angiogenesis via growth factors
Removal of endothelial cells
Use of only non‑vascular cells
Explanation - Angiogenesis is the formation of new blood vessels, vital for delivering oxygen and nutrients to cells.
Correct answer is: Promotion of angiogenesis via growth factors
Q.86 Which of the following is NOT a typical function of cartilage?
Providing a smooth surface for joint movement
Cushioning mechanical forces
Storing calcium ions
Producing lubricating fluid
Explanation - Cartilage does not store calcium; it serves as a shock absorber and smoothens joint contact.
Correct answer is: Storing calcium ions
Q.87 What does 'osteogenesis' refer to?
Formation of bone tissue
Breakdown of bone tissue
Formation of cartilage tissue
Formation of muscle tissue
Explanation - Osteogenesis is the biological process of new bone formation.
Correct answer is: Formation of bone tissue
Q.88 Which of the following best describes the 'mechanical property' of 'viscoelasticity'?
Constant deformation under load
Immediate elastic response only
Time‑dependent deformation under load
No response to load
Explanation - Viscoelastic materials exhibit both elastic and viscous behavior, deforming over time when stressed.
Correct answer is: Time‑dependent deformation under load
Q.89 Which type of cell is responsible for producing the extracellular matrix in tendon tissue?
Tenocytes
Chondrocytes
Myocytes
Neurons
Explanation - Tenocytes are specialized fibroblasts that produce collagen fibers in tendons.
Correct answer is: Tenocytes
Q.90 Which of the following is a key factor influencing the differentiation of mesenchymal stem cells into osteoblasts?
High glucose concentration
Mechanical stiffness of the substrate
Low temperature
Absence of oxygen
Explanation - Stiffer substrates tend to promote osteogenic differentiation of stem cells.
Correct answer is: Mechanical stiffness of the substrate
Q.91 Which of the following statements best describes the role of 'growth factor' in tissue engineering?
They provide mechanical strength
They are used only for staining
They act as signaling molecules to guide cell proliferation and differentiation
They are used to increase scaffold density
Explanation - Growth factors such as BMPs and VEGF provide biochemical cues that direct cell behavior during tissue formation.
Correct answer is: They act as signaling molecules to guide cell proliferation and differentiation
Q.92 What is the primary role of the 'apical surface' of epithelial cells?
To anchor to the basement membrane
To secrete mucus and interact with the external environment
To store energy
To conduct electrical signals
Explanation - The apical surface faces the lumen or external environment and often bears specialized structures like microvilli or cilia.
Correct answer is: To secrete mucus and interact with the external environment
Q.93 Which of the following best explains 'stem cell niche'?
A type of scaffold used in tissue engineering
The microenvironment that maintains stem cells in an undifferentiated state
A genetic mutation in stem cells
A type of immune cell
Explanation - Stem cell niches provide signals that preserve stemness and regulate differentiation.
Correct answer is: The microenvironment that maintains stem cells in an undifferentiated state
Q.94 In tissue engineering, why is 'surface topography' of a scaffold important?
It determines the color of the scaffold
It influences cell adhesion, alignment, and differentiation
It has no effect on cell behavior
It controls the electrical resistance of the scaffold
Explanation - Micro‑ and nanoscale topographical cues can guide how cells attach and orient themselves on a scaffold.
Correct answer is: It influences cell adhesion, alignment, and differentiation
Q.95 Which of the following best describes the 'Wnt/β‑catenin pathway'?
A pathway for ATP production
A signaling cascade that regulates stem cell self‑renewal and differentiation
A pathway that degrades proteins
A method of mechanical stimulation
Explanation - The Wnt/β‑catenin pathway is a key regulator of cell fate decisions during development and tissue regeneration.
Correct answer is: A signaling cascade that regulates stem cell self‑renewal and differentiation
Q.96 What is the main function of the 'tight junctions' in epithelial cells?
Allow free exchange of ions between cells
Prevent paracellular transport and maintain polarity
Produce growth factors
Store energy
Explanation - Tight junctions seal adjacent epithelial cells, creating a barrier and maintaining distinct apical/basolateral domains.
Correct answer is: Prevent paracellular transport and maintain polarity
Q.97 Which of the following is NOT a type of connective tissue?
Blood
Cartilage
Neural
Bone
Explanation - Neural is a type of nervous tissue, not connective tissue.
Correct answer is: Neural
Q.98 What is the purpose of 'cell‑seeded hydrogels' in cartilage tissue engineering?
To act as an electrical conductor
To provide a hydrated environment that supports chondrocyte proliferation and matrix deposition
To increase mechanical stiffness beyond bone
To deliver antibiotics
Explanation - Hydrogels mimic the high water content of cartilage, allowing cells to thrive and produce matrix.
Correct answer is: To provide a hydrated environment that supports chondrocyte proliferation and matrix deposition
Q.99 Which of the following best describes 'apoptosis'?
Uncontrolled cell proliferation
Programmed cell death
Cellular migration
Cellular fusion
Explanation - Apoptosis is a regulated process that eliminates damaged or unnecessary cells without provoking inflammation.
Correct answer is: Programmed cell death
Q.100 Which of the following is a key feature of 'myofibroblasts' in wound healing?
They secrete neurotransmitters
They produce collagen and generate contractile force
They produce insulin
They degrade all extracellular matrix
Explanation - Myofibroblasts synthesize collagen and contract, aiding wound closure and scar formation.
Correct answer is: They produce collagen and generate contractile force
Q.101 What is the role of the 'Golgi apparatus' in the secretion pathway?
To create ATP
To package proteins and lipids for transport to the plasma membrane or secretion
To store genetic material
To control cell cycle
Explanation - The Golgi modifies and sorts cargo proteins for delivery to appropriate destinations.
Correct answer is: To package proteins and lipids for transport to the plasma membrane or secretion
Q.102 Which of the following best describes the 'electrospun scaffold' in tissue engineering?
A scaffold fabricated by electrospinning fibers to create a fibrous, porous structure
A scaffold that conducts electricity
A scaffold that is fully solid and non‑porous
A scaffold that is only used for bone tissue
Explanation - Electrospinning produces nanofiber mats that mimic the fibrous architecture of many tissues.
Correct answer is: A scaffold fabricated by electrospinning fibers to create a fibrous, porous structure
Q.103 Which of the following is a major component of the blood plasma?
Glucose
Hemoglobin
Albumin
Collagen
Explanation - Albumin is the most abundant plasma protein, maintaining oncotic pressure and transporting substances.
Correct answer is: Albumin
Q.104 Which of the following best describes the 'stem cell niche' in bone marrow?
An environment that supplies stem cells with oxygen only
A specialized microenvironment that regulates stem cell maintenance and differentiation
A region devoid of growth factors
A region that only contains mature blood cells
Explanation - The bone marrow niche provides signals and physical cues that maintain stem cell quiescence or activation.
Correct answer is: A specialized microenvironment that regulates stem cell maintenance and differentiation
Q.105 What is the main function of the 'basement membrane' in the kidney's glomerulus?
To filter blood and maintain osmotic pressure
To produce hormones
To transport oxygen
To store fat
Explanation - The basement membrane in the glomerulus acts as a selective barrier for filtration during urine formation.
Correct answer is: To filter blood and maintain osmotic pressure
Q.106 Which of the following best explains the term 'stem cell pluripotency'?
The ability to differentiate into all three germ layers
The inability to divide
The capacity to become any cell type in the body
The capacity to only become blood cells
Explanation - Pluripotent stem cells can give rise to cells of ectoderm, mesoderm, and endoderm.
Correct answer is: The ability to differentiate into all three germ layers
Q.107 In tissue engineering, why is 'dynamic perfusion' often employed?
To maintain a static environment
To enhance nutrient transport and waste removal by flowing media through the scaffold
To prevent cell attachment
To increase scaffold rigidity
Explanation - Dynamic perfusion mimics blood flow, ensuring cells receive sufficient nutrients and oxygen.
Correct answer is: To enhance nutrient transport and waste removal by flowing media through the scaffold
Q.108 Which of the following best describes 'osteoclast' activity?
Synthesizing new bone matrix
Resorbing existing bone tissue
Producing cartilage matrix
Contracting muscle fibers
Explanation - Osteoclasts break down bone to facilitate remodeling and calcium mobilization.
Correct answer is: Resorbing existing bone tissue
Q.109 Which of these is a major component of the interstitial fluid in connective tissue?
Collagen fibers
Proteoglycans
Water
Fibroblasts
Explanation - Interstitium is largely water, providing a medium for nutrient and waste transport.
Correct answer is: Water
Q.110 Which of the following is NOT a typical cell type found in the blood?
Erythrocyte
Leukocyte
Platelet
Chondrocyte
Explanation - Chondrocytes are cartilage cells; they do not circulate in blood.
Correct answer is: Chondrocyte
Q.111 Which of the following best explains the purpose of 'surface functionalization' of a scaffold?
To increase its electrical resistance
To modify the surface chemistry to enhance cell attachment and signaling
To make it invisible to the immune system
To reduce its porosity
Explanation - Functional groups or proteins on a scaffold surface can improve biocompatibility and cell behavior.
Correct answer is: To modify the surface chemistry to enhance cell attachment and signaling
Q.112 What is a key characteristic of 'vascularized' tissue constructs?
They have no blood vessels
They contain a network of blood vessels that supply nutrients and oxygen
They are always synthetic
They lack cell communication
Explanation - Vascularization is critical for delivering oxygen and nutrients to large tissue constructs.
Correct answer is: They contain a network of blood vessels that supply nutrients and oxygen
Q.113 Which of the following is a function of fibroblasts in the dermis?
Produce keratin
Synthesize collagen and elastin
Generate sweat
Produce insulin
Explanation - Dermal fibroblasts are the main producers of ECM proteins that maintain skin structure.
Correct answer is: Synthesize collagen and elastin
Q.114 Which of the following best defines 'angiogenesis'?
Breakdown of bone
Formation of new blood vessels
Formation of muscle fibers
Formation of cartilage
Explanation - Angiogenesis is the growth of new capillaries from existing vessels, essential for tissue vascularization.
Correct answer is: Formation of new blood vessels
Q.115 What is the main role of the 'basement membrane' in epithelial tissues?
It stores genetic information
It anchors epithelial cells and provides a selective barrier
It conducts electrical signals
It stores energy as glycogen
Explanation - The basement membrane supports epithelial structure and regulates molecule passage.
Correct answer is: It anchors epithelial cells and provides a selective barrier
Q.116 Which of the following is a typical component of the extracellular matrix in cartilage?
Collagen type I
Collagen type II
Elastin
Fibronectin
Explanation - Cartilage predominantly contains collagen type II, which provides tensile strength specific to cartilage.
Correct answer is: Collagen type II
Q.117 Which of the following best describes the 'Wnt/β‑catenin' pathway’s role in tissue engineering?
Regulating electrical conductivity
Controlling stem cell proliferation and differentiation
Degrading scaffold materials
Inhibiting angiogenesis
Explanation - The Wnt/β‑catenin pathway influences stem cell fate decisions, impacting tissue regeneration.
Correct answer is: Controlling stem cell proliferation and differentiation
Q.118 Which of the following is the main structural protein in bone?
Collagen type I
Collagen type II
Elastin
Fibronectin
Explanation - Collagen type I is the major organic component of bone, providing tensile strength.
Correct answer is: Collagen type I
Q.119 What is the primary function of 'tight junctions' in epithelial cells?
Allow paracellular transport of ions
Create a barrier to prevent paracellular transport
Generate action potentials
Produce mucus
Explanation - Tight junctions seal gaps between adjacent cells, restricting movement of substances between them.
Correct answer is: Create a barrier to prevent paracellular transport
Q.120 Which of the following best describes 'myofibroblasts' in the context of wound healing?
Cells that secrete insulin
Cells that produce collagen and contract wound edges
Cells that generate electrical impulses
Cells that phagocytose debris
Explanation - Myofibroblasts contribute to scar formation by producing ECM and exerting contractile force.
Correct answer is: Cells that produce collagen and contract wound edges
Q.121 Which of the following is a key component of the blood plasma that helps maintain oncotic pressure?
Red blood cells
White blood cells
Albumin
Platelets
Explanation - Albumin is a plasma protein that attracts water, helping to keep fluid within vessels.
Correct answer is: Albumin
Q.122 What does the term 'bioprinting' refer to in tissue engineering?
Printing of tissue diagrams
Printing cells and biomaterials in a precise, layer‑by‑layer fashion
Printing electrical circuits on tissue
Printing only synthetic materials
Explanation - Bioprinting uses 3D printers to deposit living cells within bioinks, creating tissue constructs.
Correct answer is: Printing cells and biomaterials in a precise, layer‑by‑layer fashion
Q.123 Which of the following best describes the 'electrospun scaffold' for tissue engineering?
A scaffold created by drawing fibers with an electric field
A scaffold that is purely metallic
A scaffold that is non‑porous
A scaffold that is only used for cartilage
Explanation - Electrospinning produces nanofiber mats that mimic the fibrous structure of many tissues.
Correct answer is: A scaffold created by drawing fibers with an electric field
Q.124 Which of the following is a primary function of the Golgi apparatus?
Produce ATP
Package proteins for transport
Store genetic material
Control cell division
Explanation - The Golgi modifies, sorts, and packages proteins and lipids for delivery to the membrane or secretion.
Correct answer is: Package proteins for transport
Q.125 Which of the following best describes the 'stem cell niche' in bone marrow?
A type of scaffold used in tissue engineering
A specialized microenvironment that maintains stem cell quiescence and promotes differentiation
A region devoid of growth factors
A region that only contains mature blood cells
Explanation - The bone marrow niche supplies signals that preserve stemness and regulate activation.
Correct answer is: A specialized microenvironment that maintains stem cell quiescence and promotes differentiation