Mechanical Properties Of Biological Tissues

Question 1

Stress

Answer 1

Internal resistive force per unit area in a structure due to application of an external force
F/A

Question 2

Strain

Answer 2

Ratio of the change in length relative to the original length of the structure being stressed

Question 3

Stiffness

Answer 3

Change in force applied to tissue, divided by the change in tissues length
Elastic portion

Question 4

Normal

Answer 4

Force applied perpendicular to the contact surface
Creates compression between 2 segments

Question 5

Shear

Answer 5

Force produced as 2 compressed objects slide past each other in opposite directions (parallel to contact surface)
Creates translation between 2 segments

Question 6

Fracture strength

Answer 6

Stress/strain at which tissue fracture begins - microfracture

Question 7

Ultimate stress

Answer 7

Maximum stress required to cause failure

Question 8

Ultimate strain

Answer 8

Maximum deformation or strain that occurs before failure

Question 9

Toughness

Answer 9

Maximum energy storage before failure
Represented by area under the curve in stress-strain curve