Tissue Engineering Interview Questions and Answers for Experienced people focuses on “Natural Biomaterials – 2”.
1. Mechanical properties of alginate reduce in the presence of K+ ions.
A. TRUE
B. FALSE
Answer: A
Clarification: In a clinical trial, patients suffering from a lesion in the femoral condyle were successfully treated with the autologous chondrocytes cultured in the alginate–agarose scaffolds. However, alginate gels are relatively unstable in physiological media because of a decrease in mechanical properties of the gels due to the replacement of Ca2+ ions with Na+ or K+ ions in the polymer chains.
2. ___________ can be obtained by the deacetylation of chitin.
A. Chitosan
B. Cellulose
C. Actin
D. Fibrin
Answer: A
Clarification: Chitin on deacetylation gives Chitosan. Chitosan can be used as a biomaterial that is biomimetic in nature, this is due to its structural similarity to the GAGs in native tissues.
3. Chitosan can be dissolved only in dilute acs because of its high porosity.
A. TRUE
B. FALSE
Answer: B
Clarification: Due to the high crystallinity and a chemical structure with amino acs, only dilute acs have the ability to dissolve Chitosan.
4. Chitosan has a similar structure to Glycos-Amino-Glycans (GAGs) in cartilage.
A. TRUE
B. FALSE
Answer: A
Clarification: Chitosan is a favorite scaffold material in articular TE applications because of its similar structure to GAGs in cartilage-stimulating chondrogenesis.
5. ____________ is a natural polymer derived from collagen.
A. Gelatin
B. Keratin
C. PVC
D. Polythene
Answer: A
Clarification: Gelatin is a thermoresponsive, natural biomaterial extracted from collagen via breaking its triple-helix structure into single-strand molecules. It is more cost-effective and less antigenic than collagen.
6. ____________ consists of a network of fibrous proteins.
A. Fibrin
B. Collagen
C. Alginate
D. Gelatin
Answer: A
Clarification: Fibrin comprises a network of fibrous proteins. The structural unit of fibrin polymer is fibrinogen, which can be derived from blood coagulated as a result of an injury.
7. Fibrin is formed by the enzymatic polymerization of fibrinogen using ____________
A. thrombin
B. keratin
C. calcium
D. hydrochloric ac
Answer: A
Clarification: Fibrin gels are formed at room temperature through the enzymatic polymerization of fibrinogen using thrombin and its degradation rate can be controlled by aprotinin or tranexamic ac.
8. The major drawback of using fibrin is its shrinkage.
A. TRUE
B. FALSE
Answer: A
Clarification: A major drawback of using fibrin is its shrinkage in vivo. In addition, fibrin gel has limited mechanical strength particularly after implantation in vivo.
9. Silk is a natural biomaterial produced by ____________
A. spers
B. cockroaches
C. ants
D. earthworms
Answer: A
Clarification: Silk is a natural biomaterial produced by spers. It has been studied intensively for a long time as a biomaterial because of its low inflammatory response, biodegradability, tunable structural and chemical properties and high mechanical properties.
10. _____________ was synthesized by the reaction of silk with lactose using cyanuric chlore as the coupling spacer.
A. Galactosylated silk fibroin
B. Sulfonated silk fibroin
C. Elastin
D. Fibrin
Answer: A
Clarification: Galactosylated silk fibroin was synthesized by the reaction of silk with lactose using cyanuric chlore as the coupling spacer. Hepatocytes were able to attach to the galactosylated-silk-coated substrates by approximately eightfold higher than those attached to the untreated substrates.
11. Peptes are composed of amino acs.
A. TRUE
B. FALSE
Answer: A
Clarification: Proteins are the main constituents of all living cells. They are composed of amino ac chains. A pepte molecule is made up of more than one amino ac linked together with a pepte bond.
12. ___________ Elastin is one of the components in natural ECM.
A. Chitosan
B. Cellulose
C. Elastin
D. Fibrin
Answer: C
Clarification: Elastin is one of the components in natural ECM, proving elasticity to the different tissues in the body, such as the lungs, skin and blood vessels.
13. The half-life of elastin is 24 hours.
A. TRUE
B. FALSE
Answer: B
Clarification: The half-life of elastin in the body is almost 70 years, and elastic fibers are insoluble and highly stable in native tissues, preventing their ease of processing as a biomaterial.
Engineering for Interviews,