Q.1 What is the primary role of a scaffold in tissue engineering?
Providing mechanical support for new tissue growth
Delivering nutrients directly to cells
Acting as a drug reservoir
Replacing the need for stem cells
Explanation - Scaffolds serve as a three‑dimensional matrix that offers a structure for cells to adhere, proliferate, and organize into functional tissue.
Correct answer is: Providing mechanical support for new tissue growth
Q.2 Which material is commonly used for biodegradable polymer scaffolds?
Polyethylene
Polylactic acid (PLA)
Polystyrene
Polyethylene terephthalate (PET)
Explanation - PLA degrades into lactic acid in the body and is widely used for temporary scaffolds in regenerative medicine.
Correct answer is: Polylactic acid (PLA)
Q.3 Which property is NOT essential for a biomaterial used in bone regeneration?
Biocompatibility
Electrical conductivity
Osteoconductivity
Mechanical strength
Explanation - Bone regeneration requires biocompatibility, osteoconductivity, and mechanical support, but electrical conductivity is not a primary requirement.
Correct answer is: Electrical conductivity
Q.4 Collagen type I is often used in skin grafts because it:
Is highly elastic
Is a major component of dermal extracellular matrix
Resists enzymatic degradation
Has antibacterial properties
Explanation - Collagen I provides structural support and promotes cell adhesion, making it ideal for skin tissue engineering.
Correct answer is: Is a major component of dermal extracellular matrix
Q.5 What does 'biodegradable' mean in the context of biomaterials?
It can be reused in the laboratory
It dissolves in water
It is broken down by cells or enzymes over time
It is resistant to all chemicals
Explanation - Biodegradable materials are metabolized by biological processes, eliminating the need for surgical removal.
Correct answer is: It is broken down by cells or enzymes over time
Q.6 Which of the following is a ceramic commonly used for dental implants?
Hydroxyapatite
Polycarbonate
Silicon nitride
Polyethylene
Explanation - Hydroxyapatite mimics bone mineral and is widely used for bone and dental implants due to its osteoconductivity.
Correct answer is: Hydroxyapatite
Q.7 What is the main advantage of using decellularized extracellular matrix (dECM) for scaffolds?
It is cheaper than synthetic polymers
It contains natural growth factors and biochemical cues
It is fully synthetic and chemically defined
It degrades in hours
Explanation - dECM retains native proteins and growth factors that guide cell behavior and improve tissue integration.
Correct answer is: It contains natural growth factors and biochemical cues
Q.8 Which surface modification can increase the hydrophilicity of a polymer scaffold?
Plasma treatment
Hydrophobic coating
Annealing at high temperature
Embedding metal nanoparticles
Explanation - Plasma introduces polar groups to the surface, making polymers more hydrophilic and improving cell attachment.
Correct answer is: Plasma treatment
Q.9 Why are chitosan-based hydrogels used in wound healing?
They are rigid and provide mechanical strength
They possess antimicrobial properties and promote hemostasis
They are electrically conductive
They are fluorescent under UV light
Explanation - Chitosan is biodegradable, mucoadhesive, and has antibacterial activity, which helps in wound closure.
Correct answer is: They possess antimicrobial properties and promote hemostasis
Q.10 Which term describes a scaffold’s ability to support cell attachment and proliferation?
Hydrophobicity
Porosity
Biocompatibility
Cell affinity
Explanation - Cell affinity refers to the material’s surface properties that encourage cells to adhere and grow.
Correct answer is: Cell affinity
Q.11 What is the typical pore size range for a scaffold designed to support bone tissue regeneration?
1-10 µm
20-200 µm
300-500 µm
1-2 mm
Explanation - A pore size of 20–200 µm facilitates vascularization and osteoblast infiltration necessary for bone growth.
Correct answer is: 20-200 µm
Q.12 Which biomaterial is known for its high electrical conductivity?
Polycaprolactone (PCL)
Graphene
Polyurethane
Polylactic acid (PLA)
Explanation - Graphene is a two‑dimensional carbon material with excellent electrical conductivity, useful in nerve and cardiac tissue engineering.
Correct answer is: Graphene
Q.13 In tissue engineering, what does the term 'osteoinduction' refer to?
The scaffold’s ability to conduct electricity
The recruitment of stem cells to form bone
The scaffold’s structural support
The rate at which a scaffold degrades
Explanation - Osteoinduction is the process by which materials stimulate progenitor cells to differentiate into bone-forming cells.
Correct answer is: The recruitment of stem cells to form bone
Q.14 Which FDA-approved product is a biodegradable polymer for vascular grafts?
Dacron
Gore-Tex
Polyethylene terephthalate (PET)
Poly(lactic-co-glycolic acid) (PLGA)
Explanation - PLGA degrades into lactic and glycolic acids and is used for temporary vascular grafts approved by the FDA.
Correct answer is: Poly(lactic-co-glycolic acid) (PLGA)
Q.15 What is the primary function of growth factors in a biomaterial scaffold?
To make the scaffold rigid
To encourage cell proliferation and differentiation
To increase scaffold hydrophobicity
To act as a structural backbone
Explanation - Growth factors like BMP-2 or VEGF are incorporated into scaffolds to direct cell fate and promote tissue regeneration.
Correct answer is: To encourage cell proliferation and differentiation
Q.16 Why are titanium alloys commonly used for load‑bearing implants?
They are magnetic
They are biodegradable
They have high strength-to-weight ratio and biocompatibility
They are inexpensive
Explanation - Titanium alloys provide mechanical strength, corrosion resistance, and are well tolerated by the body.
Correct answer is: They have high strength-to-weight ratio and biocompatibility
Q.17 Which of the following is a key benefit of using hydrogels in regenerative medicine?
They are rigid and permanent
They can absorb large amounts of water, mimicking soft tissues
They are always crystalline
They do not support cell adhesion
Explanation - Hydrogels swell in physiological fluids and provide a hydrated environment similar to natural soft tissue.
Correct answer is: They can absorb large amounts of water, mimicking soft tissues
Q.18 Which technique is commonly used to create porous structures in polymer scaffolds?
Electrospinning
3D printing
Freeze-drying
All of the above
Explanation - Electrospinning, 3‑D printing, and freeze‑drying can produce porous scaffolds suited for tissue engineering.
Correct answer is: All of the above
Q.19 What role does the surface roughness of a biomaterial play?
It determines the color of the material
It influences cell attachment and differentiation
It has no biological significance
It controls electrical conductivity
Explanation - Surface roughness can enhance protein adsorption and provide topographical cues that affect cell behavior.
Correct answer is: It influences cell attachment and differentiation
Q.20 Which natural polymer is derived from algae and used for wound dressings?
Alginate
Chitosan
Gelatin
Collagen
Explanation - Alginate is extracted from seaweed, forms gels in the presence of calcium, and promotes hemostasis.
Correct answer is: Alginate
Q.21 What is a major challenge when designing a scaffold for neural tissue engineering?
Making it highly rigid
Ensuring it is electrically insulating
Promoting neuronal alignment without scar tissue
Increasing its density
Explanation - Scaffolds must provide guidance cues for neurons while minimizing glial scar formation to allow functional reconnection.
Correct answer is: Promoting neuronal alignment without scar tissue
Q.22 Which of these materials is considered a natural protein-based scaffold?
Polycaprolactone
Polylactic acid
Gelatin
Polydimethylsiloxane
Explanation - Gelatin is derived from collagen and offers cell‑binding motifs for tissue engineering.
Correct answer is: Gelatin
Q.23 Why is porosity important in a biodegradable scaffold?
It reduces manufacturing cost
It allows nutrient diffusion and cell migration
It increases mechanical strength
It makes the scaffold transparent
Explanation - High porosity ensures cells can infiltrate and blood vessels can form, essential for tissue survival.
Correct answer is: It allows nutrient diffusion and cell migration
Q.24 Which of the following is NOT a typical characteristic of a suitable bone substitute material?
Osteoconductive
Osteoinductive
Non-biodegradable
Mechanical strength comparable to bone
Explanation - Bone substitutes usually degrade over time, allowing natural bone to replace the scaffold.
Correct answer is: Non-biodegradable
Q.25 The term 'bioprinting' refers to:
Printing logos on biomaterial surfaces
Printing electronic circuits on tissues
Layer‑by‑layer fabrication of cell‑laden biomaterials
Printing tissues using pure metal
Explanation - Bioprinting constructs complex tissue structures by depositing bio‑inks containing cells and biomaterials.
Correct answer is: Layer‑by‑layer fabrication of cell‑laden biomaterials
Q.26 Which of these is a primary concern when implanting a synthetic biomaterial?
Color matching
Foreign body reaction
Weight loss
Thermal conductivity
Explanation - The immune system may react to the implant, causing inflammation or encapsulation that compromises integration.
Correct answer is: Foreign body reaction
Q.27 What is the main purpose of incorporating antibiotics into a scaffold?
To increase mechanical strength
To provide anti‑inflammatory effects
To prevent post‑surgical infections
To improve electrical signaling
Explanation - Local antibiotic delivery from scaffolds helps avoid systemic side effects while targeting the surgical site.
Correct answer is: To prevent post‑surgical infections
Q.28 Which material is commonly used for making vascular grafts due to its flexibility?
Polyethylene terephthalate (PET)
Polyglycolic acid (PGA)
Polyurethane
Polylactic acid (PLA)
Explanation - Polyurethane offers high elasticity, making it suitable for blood vessel replacements.
Correct answer is: Polyurethane
Q.29 How does a scaffold’s degradation rate affect tissue regeneration?
Faster degradation always improves integration
Slower degradation supports immediate mechanical function only
Optimal degradation matches new tissue formation rate
Degradation rate has no effect
Explanation - If a scaffold degrades too quickly, it may lose support; too slowly, it can hinder tissue formation.
Correct answer is: Optimal degradation matches new tissue formation rate
Q.30 What is the role of hydroxyapatite in bone scaffolds?
To increase electrical conductivity
To serve as a source of calcium and phosphate ions
To make the scaffold biodegradable
To reduce porosity
Explanation - Hydroxyapatite mimics bone mineral, promoting bone cell attachment and mineralization.
Correct answer is: To serve as a source of calcium and phosphate ions
Q.31 Which cell type is commonly used in regenerative medicine for producing growth factors?
Red blood cells
Adipose‑derived stem cells
Neutrophils
Platelets
Explanation - Adipose‑derived stem cells secrete a variety of growth factors that aid tissue repair.
Correct answer is: Adipose‑derived stem cells
Q.32 In the context of wound healing, what does 'exudate' refer to?
A type of biomaterial
Inflamed tissue
Fluid that drains from a wound
A bacterial infection
Explanation - Exudate is a fluid rich in proteins and cells that helps keep the wound moist and supplies nutrients.
Correct answer is: Fluid that drains from a wound
Q.33 Why are metallic biomaterials like titanium often coated with hydroxyapatite?
To improve aesthetics
To increase mechanical strength
To enhance osseointegration
To reduce cost
Explanation - Hydroxyapatite coating promotes bone cell adhesion and integration with the implant.
Correct answer is: To enhance osseointegration
Q.34 What does 'osteoconductive' mean regarding a biomaterial?
It encourages bone to form on its surface
It dissolves in bone tissue
It blocks bone growth
It is electrically conductive
Explanation - Osteoconductive materials serve as a scaffold for bone growth, guiding new bone formation.
Correct answer is: It encourages bone to form on its surface
Q.35 Which of the following best describes a 'bioink' used in 3D bioprinting?
Ink that paints a picture
A blend of cells and biomaterial that can be extruded
A chemical solution for cleaning
A type of electrical ink
Explanation - Bioinks contain living cells and support matrices for creating tissue constructs.
Correct answer is: A blend of cells and biomaterial that can be extruded
Q.36 Which biomaterial is known for its ability to support cartilage regeneration?
Polylactic acid (PLA)
Hydroxyapatite
Chondroitin sulfate
Titanium alloy
Explanation - Chondroitin sulfate is a glycosaminoglycan that promotes chondrocyte proliferation and ECM production.
Correct answer is: Chondroitin sulfate
Q.37 Which technique is used to measure the mechanical stiffness of a scaffold?
SEM imaging
Nanoindentation
X‑ray diffraction
Raman spectroscopy
Explanation - Nanoindentation applies a small force to measure the elastic modulus of soft materials.
Correct answer is: Nanoindentation
Q.38 What is a typical application of silk fibroin in regenerative medicine?
As a biodegradable electrical conductor
As a drug delivery vehicle in hydrogel form
As a synthetic polymer for bone replacement
As a mineral filler
Explanation - Silk fibroin can form hydrogels that encapsulate drugs or cells for controlled release.
Correct answer is: As a drug delivery vehicle in hydrogel form
Q.39 Which property is NOT crucial for a material intended for cardiac patch applications?
Electrical conductivity
Mechanical compliance with heart tissue
Rapid biodegradation
Biocompatibility
Explanation - Cardiac patches need to persist long enough for tissue remodeling; rapid degradation would compromise support.
Correct answer is: Rapid biodegradation
Q.40 Which biomaterial can be sterilized by gamma irradiation without significant loss of mechanical integrity?
Polyethylene terephthalate (PET)
Polyglycolic acid (PGA)
Polylactic acid (PLA)
Silicone rubber
Explanation - Silicone is resistant to gamma radiation, making it suitable for sterilizing implants.
Correct answer is: Silicone rubber
Q.41 Why are collagen sponges often used in wound dressings?
They are highly conductive
They provide a scaffold for cell migration and absorb exudate
They are biodegradable and fluorescent
They prevent any cellular infiltration
Explanation - Collagen sponges support tissue ingrowth while managing wound moisture.
Correct answer is: They provide a scaffold for cell migration and absorb exudate
Q.42 Which factor primarily determines the immunogenicity of a biomaterial?
Surface roughness
Chemical composition
Mechanical stiffness
Color
Explanation - The chemical nature of a material dictates how the immune system recognizes and reacts to it.
Correct answer is: Chemical composition
Q.43 Which of these materials is NOT typically classified as a synthetic polymer for scaffolds?
Polycaprolactone (PCL)
Polylactic acid (PLA)
Gelatin
Polyethylene glycol (PEG)
Explanation - Gelatin is a natural protein, not a synthetic polymer.
Correct answer is: Gelatin
Q.44 What is the purpose of crosslinking in hydrogels?
To dissolve them faster
To increase their mechanical stability
To make them fluorescent
To remove cells
Explanation - Crosslinking creates covalent or ionic bonds that reinforce the hydrogel network.
Correct answer is: To increase their mechanical stability
Q.45 Which natural polymer is known for its strong antibacterial activity?
Alginate
Chitosan
Polyethylene glycol (PEG)
Polylactic acid (PLA)
Explanation - Chitosan’s polycationic nature disrupts bacterial membranes, providing antibacterial properties.
Correct answer is: Chitosan
Q.46 The term 'osteoclast' refers to:
A cell that builds bone
A cell that degrades bone
A type of biomaterial
An imaging technique
Explanation - Osteoclasts resorb bone tissue, balancing bone remodeling.
Correct answer is: A cell that degrades bone
Q.47 Which property of a scaffold is measured by the Young’s modulus?
Its pore size
Its density
Its stiffness
Its color
Explanation - Young’s modulus quantifies the material’s resistance to elastic deformation.
Correct answer is: Its stiffness
Q.48 Which technique is often used to evaluate cell viability on a scaffold?
SEM imaging
Live/Dead staining
X‑ray diffraction
Electrophoresis
Explanation - Live/Dead assays use fluorescent dyes to differentiate living from dead cells on a material.
Correct answer is: Live/Dead staining
Q.49 What does 'bioreactor' refer to in tissue engineering?
A type of biomaterial
A device that mimics physiological conditions
An imaging technique
A type of scaffold
Explanation - Bioreactors provide controlled environments (flow, oxygen, mechanical stimuli) for growing tissues.
Correct answer is: A device that mimics physiological conditions
Q.50 Which of the following is a common method for sterilizing polymer scaffolds?
Autoclaving at 121°C
Gamma irradiation
Dry heat at 200°C
All of the above
Explanation - All listed methods can sterilize polymers, though some materials may be sensitive to heat or radiation.
Correct answer is: All of the above
Q.51 In bone tissue engineering, what does 'osteogenic differentiation' mean?
Formation of bone marrow
Stem cells becoming bone cells
Bone resorption
Bone remodeling
Explanation - Osteogenic differentiation is the process by which precursor cells mature into osteoblasts that produce bone matrix.
Correct answer is: Stem cells becoming bone cells
Q.52 Which biomaterial is commonly used for creating microfluidic channels in tissue scaffolds?
Polydimethylsiloxane (PDMS)
Polyethylene terephthalate (PET)
Polylactic acid (PLA)
Gelatin
Explanation - PDMS is flexible, optically transparent, and easy to mold into micro‑scale channels.
Correct answer is: Polydimethylsiloxane (PDMS)
Q.53 Which surface chemistry modification improves protein adsorption on a polymer scaffold?
Hydrophobic coating
Polyethylene glycol (PEG) grafting
Introduction of carboxyl groups
Annealing at high temperature
Explanation - Carboxyl groups provide negative charges that attract proteins and enhance cell adhesion.
Correct answer is: Introduction of carboxyl groups
Q.54 Which of these is a characteristic of a 'bioactive glass'?
It dissolves quickly and is toxic
It releases ions that stimulate bone formation
It is non‑degradable
It is purely inert
Explanation - Bioactive glass releases Ca²⁺ and PO₄³⁻ ions, stimulating osteoblast activity and bone bonding.
Correct answer is: It releases ions that stimulate bone formation
Q.55 Why is 'mimicking the extracellular matrix (ECM)' important in scaffold design?
To reduce cost
To ensure mechanical strength only
To provide biochemical and mechanical cues similar to natural tissue
To increase electrical conductivity
Explanation - ECM‑like scaffolds guide cell behavior, proliferation, and differentiation similar to natural environments.
Correct answer is: To provide biochemical and mechanical cues similar to natural tissue
Q.56 Which technique can be used to create hierarchical porosity in a scaffold?
Electrospinning
3D printing with sacrificial fibers
Freeze‑casting
All of the above
Explanation - Each method can generate multiple pore sizes, creating a hierarchical structure conducive to cell infiltration.
Correct answer is: All of the above
Q.57 What is the primary role of 'growth factors' in regenerative medicine?
To act as structural components
To provide mechanical support
To signal cells to divide and differentiate
To increase scaffold stiffness
Explanation - Growth factors like VEGF and BMPs guide cellular processes essential for tissue regeneration.
Correct answer is: To signal cells to divide and differentiate
Q.58 Which biomaterial is best known for its use in cartilage repair due to its high water content?
Polyethylene glycol (PEG)
Polylactic acid (PLA)
Hydroxyapatite
Chondroitin sulfate
Explanation - Chondroitin sulfate is a key component of cartilage extracellular matrix and retains high water content.
Correct answer is: Chondroitin sulfate
Q.59 In a hydrogel, what does the term 'gelation time' refer to?
The time it takes to dissolve the hydrogel
The time taken for the liquid precursor to become a solid gel
The time required for cells to attach
The time for hydrogel to degrade
Explanation - Gelation time determines how quickly the material solidifies, affecting cell encapsulation and handling.
Correct answer is: The time taken for the liquid precursor to become a solid gel
Q.60 Which material is considered a 'bio‑inert' surface?
Gold
Polyethylene glycol (PEG)
Titanium alloy
Polylactic acid (PLA)
Explanation - Gold surfaces are chemically inert and elicit minimal immune responses, making them useful in some biomedical devices.
Correct answer is: Gold
Q.61 What is a key advantage of using decellularized bone matrix for grafts?
It is easily available in large quantities
It contains no proteins
It retains natural bone structure and biochemical signals
It degrades instantly
Explanation - Decellularized bone preserves the native architecture and signals that promote bone regeneration.
Correct answer is: It retains natural bone structure and biochemical signals
Q.62 Which of the following is NOT a type of biomaterial used for drug delivery?
Polylactic acid (PLA)
Hydrogel
Polyethylene glycol (PEG)
Glass
Explanation - While glass can be bioactive, it is not commonly used as a drug delivery vehicle compared to polymers or hydrogels.
Correct answer is: Glass
Q.63 Which property is critical for a material used as a corneal implant?
High opacity
Transparency and mechanical flexibility
High electrical conductivity
Fast degradation
Explanation - Corneal implants must allow light passage and flex with eye movements without cracking.
Correct answer is: Transparency and mechanical flexibility
Q.64 What does the term 'mechanotransduction' refer to in tissue engineering?
Conversion of mechanical stimuli into cellular signals
Measurement of scaffold stiffness
Electrical conduction in cells
Biodegradation rate of polymers
Explanation - Mechanotransduction is how cells sense and respond to mechanical forces, influencing differentiation.
Correct answer is: Conversion of mechanical stimuli into cellular signals
Q.65 Which material is frequently used as a 3D printing filament for bone scaffolds due to its biocompatibility?
PLA (polylactic acid)
ABS
PETG
Nylon
Explanation - PLA is biodegradable, easy to print, and widely used for bone tissue scaffolds.
Correct answer is: PLA (polylactic acid)
Q.66 In tissue engineering, what is the purpose of using 'bioactive ions' such as zinc and copper?
To increase scaffold color
To promote angiogenesis and reduce oxidative stress
To make the scaffold conductive
To accelerate degradation
Explanation - Zinc and copper ions support new blood vessel formation and act as antioxidant agents.
Correct answer is: To promote angiogenesis and reduce oxidative stress
Q.67 Which technique can create a gradient of mechanical stiffness within a single scaffold?
Layer‑by‑layer printing
Electrospinning with variable voltage
Solvent casting
All of the above
Explanation - All these methods can produce varying stiffness across a scaffold, mimicking native tissue gradients.
Correct answer is: All of the above
Q.68 Which biomaterial has the highest known biocompatibility for long‑term implants?
Polyglycolic acid (PGA)
Polyurethane
Titanium alloy
Polyethylene terephthalate (PET)
Explanation - Titanium alloys have excellent long‑term biocompatibility and corrosion resistance.
Correct answer is: Titanium alloy
Q.69 What does 'hydrogel swelling ratio' measure?
The amount of water the hydrogel can retain
Its electrical conductivity
The degradation speed
Its color change in water
Explanation - The swelling ratio indicates how much fluid a hydrogel can absorb relative to its dry weight.
Correct answer is: The amount of water the hydrogel can retain
Q.70 Which of the following is an example of a natural biomaterial used for bone replacement?
Polylactic acid (PLA)
Hydroxyapatite
Polydimethylsiloxane (PDMS)
Polyethylene terephthalate (PET)
Explanation - Hydroxyapatite is a natural mineral component of bone, often used in bone grafts.
Correct answer is: Hydroxyapatite
Q.71 Why is 'biomechanical mismatch' a concern for implanted scaffolds?
It causes increased electrical signals
It leads to scaffold color change
It can cause tissue failure or implant rejection
It has no impact
Explanation - If a scaffold’s mechanical properties differ too much from native tissue, it can impede integration.
Correct answer is: It can cause tissue failure or implant rejection
Q.72 Which cell type is typically used for producing 'biologic dressings' in wound healing?
Red blood cells
Fibroblasts
Neutrophils
Erythrocytes
Explanation - Fibroblasts produce collagen and growth factors essential for tissue repair in dressings.
Correct answer is: Fibroblasts
Q.73 What does the abbreviation 'MSCs' stand for?
Muscle Stem Cells
Mesenchymal Stem Cells
Mastoid Stem Cells
Monocyte Stem Cells
Explanation - MSCs are multipotent cells that can differentiate into bone, cartilage, and fat cells.
Correct answer is: Mesenchymal Stem Cells
Q.74 Which property of a scaffold influences its ability to promote blood vessel formation?
Porosity
Color
Electrical resistance
Density
Explanation - Adequate porosity allows endothelial cells to migrate and form new capillaries.
Correct answer is: Porosity
Q.75 Which type of polymer is commonly used for making nerve conduits due to its flexibility?
Polyethylene terephthalate (PET)
Polyethylene glycol (PEG)
Polyurethane (PU)
Polylactic acid (PLA)
Explanation - Polyurethane is elastic and can guide nerve regrowth through a flexible conduit.
Correct answer is: Polyurethane (PU)
Q.76 What is the main function of a 'bioreactor' when used in cartilage tissue engineering?
To sterilize the construct
To provide dynamic compression and fluid flow
To make the scaffold rigid
To reduce cell viability
Explanation - Bioreactors supply mechanical stimuli that mimic joint movement, enhancing cartilage formation.
Correct answer is: To provide dynamic compression and fluid flow
Q.77 Which biomaterial is often used as a matrix for stem cell delivery in the brain?
Polylactic acid (PLA)
Hydroxyapatite
Chondroitin sulfate
Alginate
Explanation - Alginate gels can encapsulate stem cells and are minimally invasive for neural delivery.
Correct answer is: Alginate
Q.78 Why are 'fibrin gels' used in wound healing?
They are opaque
They provide a scaffold for cell migration and release growth factors
They are non‑biodegradable
They are electrically conductive
Explanation - Fibrin gels mimic the natural clot, supporting tissue repair and delivering key molecules.
Correct answer is: They provide a scaffold for cell migration and release growth factors
Q.79 Which property is most important for a material used in dental implants?
Electrical conductivity
Radiopacity
Osseointegration
Fluorescence
Explanation - Osseointegration is the direct bone-to-implant interface essential for implant stability.
Correct answer is: Osseointegration
Q.80 In the context of bone healing, what does 'osteoblast' refer to?
A type of immune cell
A bone-forming cell
An enzyme that degrades bone
A vascular cell
Explanation - Osteoblasts synthesize bone matrix and are key to bone regeneration.
Correct answer is: A bone-forming cell
Q.81 Which biomaterial property is evaluated by the term 'contact angle'?
Surface wettability
Electrical resistance
Biodegradation rate
Thermal stability
Explanation - The contact angle indicates how hydrophilic or hydrophobic a surface is.
Correct answer is: Surface wettability
Q.82 What is the advantage of using 'nanoparticles' in drug‑laden scaffolds?
They increase color intensity
They provide targeted and controlled drug release
They reduce scaffold porosity
They make the scaffold magnetic
Explanation - Nanoparticles can release drugs in a controlled manner and target specific cells or tissues.
Correct answer is: They provide targeted and controlled drug release
Q.83 Which of the following is an example of a 'bio‑inert' polymer?
Polylactic acid (PLA)
Polyethylene glycol (PEG)
Chitosan
Hydroxyapatite
Explanation - PEG is hydrophilic and resists protein adsorption, making it biochemically inert.
Correct answer is: Polyethylene glycol (PEG)
Q.84 Which biomaterial can be used as a scaffold for bone repair that also acts as a source of calcium ions?
Polylactic acid (PLA)
Polyethylene glycol (PEG)
Calcium sulfate
Polyurethane
Explanation - Calcium sulfate dissolves and releases calcium, promoting bone mineralization.
Correct answer is: Calcium sulfate
Q.85 Which type of mechanical loading is applied to cartilage constructs in a bioreactor to promote matrix synthesis?
Static compression
Dynamic compression
Shear flow
All of the above
Explanation - Dynamic compression mimics joint loading, stimulating cartilage cells to produce ECM.
Correct answer is: Dynamic compression
Q.86 Which biomaterial is a 'polymer' that is commonly used for making sutures due to its high strength?
Polyethylene terephthalate (PET)
Polylactic acid (PLA)
Chitosan
Hydroxyapatite
Explanation - PET (Dacron) is a strong synthetic polymer used in many suture applications.
Correct answer is: Polyethylene terephthalate (PET)
Q.87 What is the main reason for incorporating 'silver nanoparticles' into wound dressings?
To increase mechanical strength
To provide a metallic sheen
To impart antimicrobial properties
To speed up scaffold degradation
Explanation - Silver nanoparticles release ions that kill bacteria and reduce infection risk.
Correct answer is: To impart antimicrobial properties
Q.88 Which of the following describes a 'hydrophilic' biomaterial?
Repels water
Attracts water and is water‑absorbing
Conducts electricity
Is transparent
Explanation - Hydrophilic materials readily absorb water and interact well with aqueous environments.
Correct answer is: Attracts water and is water‑absorbing
Q.89 Which imaging technique can be used to assess the integration of a scaffold in vivo?
MRI
X‑ray radiography
CT scan
All of the above
Explanation - MRI, X‑ray, and CT can each visualize scaffold integration depending on material properties.
Correct answer is: All of the above
Q.90 What is the primary advantage of using a 'biodegradable' scaffold in tissue engineering?
It can be permanently implanted
It eliminates the need for a second surgery to remove it
It is cheaper
It is stronger
Explanation - Biodegradable scaffolds degrade in the body, allowing natural tissue to replace them without removal.
Correct answer is: It eliminates the need for a second surgery to remove it
Q.91 Which material is known for its 'superelastic' behavior, useful in stents?
Polyethylene terephthalate (PET)
Nitinol (NiTi alloy)
Polylactic acid (PLA)
Chitosan
Explanation - Nitinol exhibits shape memory and superelasticity, enabling it to recover after deformation.
Correct answer is: Nitinol (NiTi alloy)
Q.92 Which of these is a common method to control the degradation rate of a polymer scaffold?
Altering the polymer’s crystallinity
Changing the pore size
Modifying the crosslink density
All of the above
Explanation - Crystallinity, porosity, and crosslinking all influence how quickly a polymer degrades.
Correct answer is: All of the above
Q.93 Which biomaterial is typically used to create a porous scaffold for bone regeneration via sintering?
Polylactic acid (PLA)
Hydroxyapatite powder
Polydimethylsiloxane (PDMS)
Chitosan
Explanation - Sintered hydroxyapatite produces a porous, load‑bearing scaffold suitable for bone tissue engineering.
Correct answer is: Hydroxyapatite powder
Q.94 In regenerative medicine, what is meant by 'cell‑scaffold interaction'?
The electrical signal between cells
The mechanical fit of the scaffold
The biological communication between cells and the material surface
The color change of the scaffold
Explanation - Cell‑scaffold interaction involves adhesion, signaling, and differentiation influenced by material properties.
Correct answer is: The biological communication between cells and the material surface
Q.95 Which biomaterial is known for its ability to form 'nanofibrous' structures that mimic native ECM?
Polylactic acid (PLA)
Polyethylene glycol (PEG)
Polyurethane (PU)
Chitosan
Explanation - PLA can be electrospun into nanofibers that replicate the architecture of natural extracellular matrix.
Correct answer is: Polylactic acid (PLA)
Q.96 What is the main benefit of incorporating 'silk fibroin' into a scaffold?
It provides electrical conductivity
It increases degradation rate
It offers mechanical strength and biocompatibility
It is highly hydrophobic
Explanation - Silk fibroin has excellent tensile strength and is biocompatible, making it suitable for load‑bearing scaffolds.
Correct answer is: It offers mechanical strength and biocompatibility
Q.97 Which technique can be used to evaluate the porosity of a scaffold?
Scanning electron microscopy (SEM)
Porosimetry
X‑ray diffraction
All of the above
Explanation - Porosimetry directly measures pore size and volume distribution within a scaffold.
Correct answer is: Porosimetry
Q.98 Which of the following materials is known to be 'bioactive' when implanted in bone?
Polylactic acid (PLA)
Polyglycolic acid (PGA)
Calcium sulfate
Polyurethane (PU)
Explanation - Calcium sulfate not only degrades but also stimulates bone formation by releasing calcium ions.
Correct answer is: Calcium sulfate
Q.99 What is the primary purpose of adding 'growth factor-loaded microspheres' to a scaffold?
To increase scaffold stiffness
To provide a controlled release of signaling molecules
To make the scaffold magnetic
To reduce porosity
Explanation - Microspheres allow sustained delivery of growth factors, enhancing tissue regeneration.
Correct answer is: To provide a controlled release of signaling molecules
Q.100 Which biomaterial is most suitable for creating a 'soft tissue' scaffold that mimics skin?
Polyethylene terephthalate (PET)
Hydroxyapatite
Polyurethane (PU)
Calcium phosphate
Explanation - PU has low modulus and high elasticity, resembling the mechanical behavior of skin.
Correct answer is: Polyurethane (PU)
Q.101 Which of the following is NOT a common method for sterilizing biomaterials?
Ethylene oxide gas
Gamma radiation
High‑temperature autoclaving
Boiling water at 100°C for 10 minutes
Explanation - Most biomaterials cannot withstand the temperature or pressure of a standard autoclave or boiling water.
Correct answer is: Boiling water at 100°C for 10 minutes
Q.102 What does 'osteoconductive' specifically refer to in scaffold design?
It degrades into bone cells
It acts as a scaffold for bone growth without influencing cell differentiation
It contains growth factors
It is electrically conductive
Explanation - Osteoconductive materials provide a surface that supports bone ingrowth but do not actively induce differentiation.
Correct answer is: It acts as a scaffold for bone growth without influencing cell differentiation
Q.103 Which material can be used to create 'micro‑channels' for vascularization within a scaffold?
Polyethylene glycol (PEG)
Polylactic acid (PLA)
Polycaprolactone (PCL)
All of the above
Explanation - PEG, PLA, and PCL can all be patterned or fabricated to form micro‑channel networks.
Correct answer is: All of the above
Q.104 What is the key difference between 'hydrophilic' and 'hydrophobic' biomaterials?
Color difference
Water affinity
Electrical conductivity
Degradation rate
Explanation - Hydrophilic materials attract water; hydrophobic materials repel it, influencing cell behavior.
Correct answer is: Water affinity
Q.105 Which of the following is a common additive used to improve the mechanical strength of a hydrogel?
Silane coupling agent
Carbon nanotubes
Silver nanoparticles
All of the above
Explanation - All these additives can reinforce hydrogels by forming crosslinks or adding mechanical load‑bearing capacity.
Correct answer is: All of the above
Q.106 What does the 'contact angle' of a material indicate?
Its electrical conductivity
Its wettability or hydrophobicity
Its degradation speed
Its color
Explanation - A low contact angle indicates high wettability (hydrophilic), while a high angle indicates hydrophobicity.
Correct answer is: Its wettability or hydrophobicity
Q.107 Which biomaterial is known for its high biocompatibility and is used in long‑term cardiac patches?
Polyglycolic acid (PGA)
Polylactic acid (PLA)
Polyethylene glycol (PEG)
Polyurethane (PU)
Explanation - PU offers elastic, biocompatible properties suitable for dynamic heart tissue environments.
Correct answer is: Polyurethane (PU)
Q.108 What is the primary advantage of using 'hydrogel' as a delivery vehicle for stem cells?
It provides a rigid matrix
It protects cells from mechanical stress and allows nutrient diffusion
It accelerates cell death
It makes cells fluorescent
Explanation - Hydrogels create a soft, hydrated environment that protects and nourishes encapsulated cells.
Correct answer is: It protects cells from mechanical stress and allows nutrient diffusion
Q.109 Which type of biomaterial is commonly used for creating bone grafts that also acts as a source of phosphate ions?
Polylactic acid (PLA)
Polydimethylsiloxane (PDMS)
Calcium phosphate
Polyurethane (PU)
Explanation - Calcium phosphate releases phosphate ions, aiding in new bone mineral formation.
Correct answer is: Calcium phosphate
Q.110 Which biomaterial property is evaluated by measuring its 'Young’s modulus'?
Its density
Its stiffness
Its degradation rate
Its color change in water
Explanation - Young’s modulus quantifies how resistant a material is to elastic deformation under load.
Correct answer is: Its stiffness
Q.111 In the design of a scaffold for cardiac tissue, why is 'electrical conductivity' important?
It helps cells to generate heat
It allows electrical signals to propagate between cardiomyocytes
It prevents scaffold degradation
It reduces porosity
Explanation - Electrical conductivity in cardiac patches facilitates synchronized contraction of heart muscle cells.
Correct answer is: It allows electrical signals to propagate between cardiomyocytes
Q.112 Which natural polymer is derived from seaweed and is used for wound dressing due to its gel‑forming ability?
Alginate
Chitosan
Collagen
Gelatin
Explanation - Alginate forms a gel in the presence of calcium ions, creating a moist environment favorable for healing.
Correct answer is: Alginate
Q.113 What does the 'biocompatibility' of a material refer to?
Its color under UV
Its ability to support cell growth without causing adverse immune responses
Its mechanical strength
Its degradation rate
Explanation - Biocompatibility is the property that allows materials to interact safely with biological tissues.
Correct answer is: Its ability to support cell growth without causing adverse immune responses
Q.114 Which technique can be used to create a scaffold with a gradient of pore sizes?
Layer‑by‑layer 3D printing
Electrospinning with variable voltage
Freeze‑casting with a temperature gradient
All of the above
Explanation - All listed methods can generate spatial gradients in pore size to mimic complex tissues.
Correct answer is: All of the above
Q.115 Which of the following is a key feature of a 'bioactive glass' used in bone regeneration?
It is non‑degradable
It releases bioactive ions that promote bone healing
It is highly magnetic
It is fluorescent
Explanation - Bioactive glass dissolves, releasing ions that stimulate osteogenesis and vascularization.
Correct answer is: It releases bioactive ions that promote bone healing
Q.116 What is the purpose of crosslinking in a hydrogel scaffold?
To increase its stiffness
To reduce cell adhesion
To make it opaque
To speed up degradation
Explanation - Crosslinking creates covalent bonds that strengthen the hydrogel network and control mechanical properties.
Correct answer is: To increase its stiffness
Q.117 Which property of a biomaterial is evaluated by measuring its 'contact angle'?
Wettability
Electrical conductivity
Thermal stability
Color intensity
Explanation - The contact angle reflects how a liquid droplet spreads on a surface, indicating hydrophilicity or hydrophobicity.
Correct answer is: Wettability
Q.118 Which biomaterial is commonly used to fabricate 'micro‑fluidic devices' for cell culture?
PDMS (polydimethylsiloxane)
PLA (polylactic acid)
Calcium sulfate
Titanium alloy
Explanation - PDMS is flexible, optically clear, and easy to mold into microfluidic channels for cell culture.
Correct answer is: PDMS (polydimethylsiloxane)
Q.119 What does 'biodegradability' mean for a scaffold used in tissue engineering?
It is permanent and never degrades
It slowly breaks down into non‑toxic byproducts
It dissolves instantly
It resists all enzymes
Explanation - Biodegradable scaffolds degrade at a rate that matches tissue growth, producing harmless metabolites.
Correct answer is: It slowly breaks down into non‑toxic byproducts
Q.120 Which biomaterial is known for its high mechanical strength and is used in load‑bearing implants?
Polylactic acid (PLA)
Polyethylene glycol (PEG)
Titanium alloy
Chitosan
Explanation - Titanium alloys provide high strength, corrosion resistance, and biocompatibility for orthopedic implants.
Correct answer is: Titanium alloy
Q.121 Which of the following is a common method to assess cell viability on a scaffold?
Live/Dead assay
X‑ray diffraction
Scanning electron microscopy (SEM)
Thermogravimetric analysis (TGA)
Explanation - Live/Dead staining distinguishes living from dead cells, providing a quick viability assessment.
Correct answer is: Live/Dead assay
Q.122 What is the main role of 'growth factors' in tissue regeneration?
To increase scaffold stiffness
To promote cell migration, proliferation, and differentiation
To change scaffold color
To accelerate degradation
Explanation - Growth factors act as biochemical cues that guide cells during tissue repair and regeneration.
Correct answer is: To promote cell migration, proliferation, and differentiation
Q.123 Which of the following best describes a 'bioactive' scaffold?
It remains inert in the body
It actively interacts with surrounding tissues to promote regeneration
It degrades immediately
It is non‑degradable
Explanation - Bioactive scaffolds release signals or ions that stimulate tissue growth and integration.
Correct answer is: It actively interacts with surrounding tissues to promote regeneration
Q.124 Which biomaterial is commonly used as a scaffold for bone tissue engineering due to its similarity to natural bone mineral?
Polylactic acid (PLA)
Hydroxyapatite
Silicone rubber
Polydimethylsiloxane (PDMS)
Explanation - Hydroxyapatite closely matches bone mineral composition and promotes osteoconductivity.
Correct answer is: Hydroxyapatite
Q.125 What is the primary advantage of using 'hydrogel' for drug delivery?
It provides a rigid delivery system
It allows for controlled release and maintains a moist environment
It increases electrical conductivity
It reduces pore size
Explanation - Hydrogels swell, releasing drugs slowly while preserving a hydrated microenvironment.
Correct answer is: It allows for controlled release and maintains a moist environment
Q.126 Which biomaterial is typically used in 'tissue‑engineered skin' due to its excellent biocompatibility?
Polyglycolic acid (PGA)
Collagen
Polystyrene
Polyethylene terephthalate (PET)
Explanation - Collagen is a major component of skin ECM and supports cell attachment and proliferation.
Correct answer is: Collagen
Q.127 Which term describes a scaffold’s ability to mimic the mechanical properties of the target tissue?
Osteoconductivity
Mechanical compliance
Electrical conductivity
Biodegradability
Explanation - Mechanical compliance refers to how well a scaffold’s stiffness matches the native tissue.
Correct answer is: Mechanical compliance
Q.128 Which of the following is a commonly used natural polymer for making cartilage scaffolds?
Polyethylene glycol (PEG)
Chondroitin sulfate
Polylactic acid (PLA)
Polydimethylsiloxane (PDMS)
Explanation - Chondroitin sulfate is a glycosaminoglycan that promotes chondrocyte proliferation and matrix production.
Correct answer is: Chondroitin sulfate
Q.129 Which property of a biomaterial is assessed by measuring its 'contact angle'?
Wettability
Electrical conductivity
Degradation rate
Color intensity
Explanation - The contact angle indicates how hydrophilic or hydrophobic a surface is.
Correct answer is: Wettability
Q.130 Which material is used to create a 'soft tissue' scaffold that mimics the elasticity of skin?
Polyethylene terephthalate (PET)
Polylactic acid (PLA)
Polyurethane (PU)
Calcium phosphate
Explanation - PU has a low modulus and high elasticity, resembling the mechanical behavior of soft tissues.
Correct answer is: Polyurethane (PU)
Q.131 Which technique can be used to create a scaffold with a gradient of pore sizes?
Layer‑by‑layer 3D printing
Electrospinning with variable voltage
Freeze‑casting with a temperature gradient
All of the above
Explanation - All listed methods can generate spatial gradients in pore size to mimic complex tissues.
Correct answer is: All of the above
Q.132 What does the 'biocompatibility' of a material refer to?
Its color under UV
Its ability to support cell growth without causing adverse immune responses
Its mechanical strength
Its degradation rate
Explanation - Biocompatibility is the property that allows materials to interact safely with biological tissues.
Correct answer is: Its ability to support cell growth without causing adverse immune responses
Q.133 Which of the following is a key feature of a 'bioactive glass' used in bone regeneration?
It is non‑degradable
It releases bioactive ions that promote bone healing
It is highly magnetic
It is fluorescent
Explanation - Bioactive glass dissolves, releasing ions that stimulate osteogenesis and vascularization.
Correct answer is: It releases bioactive ions that promote bone healing
Q.134 What is the purpose of crosslinking in a hydrogel scaffold?
To increase its stiffness
To reduce cell adhesion
To make it opaque
To speed up degradation
Explanation - Crosslinking creates covalent bonds that strengthen the hydrogel network and control mechanical properties.
Correct answer is: To increase its stiffness
Q.135 Which biomaterial can be used to create a 'soft tissue' scaffold that mimics the elasticity of skin?
Polyethylene terephthalate (PET)
Polylactic acid (PLA)
Polyurethane (PU)
Calcium phosphate
Explanation - PU has a low modulus and high elasticity, resembling the mechanical behavior of soft tissues.
Correct answer is: Polyurethane (PU)