test 3

Question 1

State and describe a technique to measure thermal properties of polymers?

Answer 1

Thermogravimetry-Technique based on the monitoring and recording of the changes in weight of a sample as it undergoes controlled thermal degradation, with varying temperature or time.

Question 2

what is the sequence of host reactions following implantation of medical devices?

Answer 2

Injury
• Blood-material interactions
• Provisional matrix formation
• Acute inflammation
• Chronic inflammation
• Granulation tissue
• Foreign-body reaction
• Fibrous capsule development

Question 3

what is resolution?

Answer 3

Presence of implant prevents attainment of original condition but a steady state can be attained which is termed as resolution

Question 4

what is the objective of blood clotting?

Answer 4

objective is to form a patch that isolates the leak and stops blood loss

Question 5

what is the difference between immunity and allergy?

Answer 5

Immunity is the property of being secure or nonsusceptible to the adverse effects of foreign agents

Allergy is the property of being especially sensitive (or hypersensitive) to foreign agents

Question 6

name 3 cells that actively take part in the sequence of local events following implantation

Answer 6

• granulocytes
• leukocyte
• macrophage

Question 7

what are granulocytes

Answer 7

any blood cell containing specific granules

Examples: neutrophils, basophils, eosinophils

Question 8

give 2 characteristics of platelets

Answer 8

“little plates” non nucleated, disc shaped

produced in bone marrow

Question 9

what is a leukocyte?

Answer 9

a colorless (white) blood cell capable of ameboid movement

(e.g. lymphocytes, monocytes, granulocytes)

Question 10

Fibrinolytic system removes unwanted ______ deposits to improve blood flow and facilitate healing process

Answer 10

Fibrinolytic system removes unwanted fibrin deposits to improve blood flow and facilitate healing process

Question 11

______ is the first in the sequence of host reaction following implantation of medical devices

Answer 11

**Injury **is the first….

Question 12

what is body’s response to damaged blood vessels

Answer 12

blood coagulation or clotting

Question 13

what is tumorigenesis

Answer 13

tumor formation around implanted devices

Question 14

Differentiate between benign and malignant tumors

Answer 14

Benign- do not invade adjacent tumors nor do they metastasize

**malignant- **tend to invade to adjacent tissues

metastasize via blood and lymph vessels

Question 15

what is the function of mitochondria

Answer 15

produces most of the cells ATP

Question 16

the DNA is contained within the __________

Answer 16

nucleus

Question 17

what is the extracellular matrix (ECM) and what are the componets?

Answer 17

Interconnected network of macromolecules present between cells 
• Composed of large number of proteins and polysaccharides
 • ECM exerts control over many cellular fate processes through binding to class of receptors.
 • For eg cell migration, adhesion, cell shape varies with ECM density

components

Collagen
• Elastin
• Proteoglycans
• Glycoproteins

Question 18

what are the types of cell junctions?

Answer 18

Tight Junctions: Form when adjacent cell membranes adhere to each other, preventing even small molecules from passing between cells
• Gap Junctions: Small hydrophilic channels created by a plaque like structure that connects two different cell membranes
• desmosomes : mechanical attachment of two cells, either in broad bands (belt desmosomes) or is specific spots (spot desmosomes)

Question 19

what are the 4 cell adaptive responses?

Answer 19

Question 20

name componets of ECM

Answer 20

Collagen
• Elastin
• Proteoglycans
• Glycoproteins
• Other ECM Components

Question 21

the two methods of cell death are _____ and ________

Answer 21

necrosis

apoptosis

Question 22

what are gap junctions?

Answer 22

Gap Junctions: Small hydrophilic channels created by a plaque like structure that connects two different cell membranes

Question 23

what are the building blocks of proteins

Answer 23

amino acids

Question 24

name 3 structures inside the cell

Answer 24

ribosome

lysosome

mitochondria

Question 25

What is gel permeation chromatography

Answer 25

an extremely powerful method for determining molecular weight distribution of a polymer

Question 26

what principle is thermogravimetry analysis based on?

Answer 26

Technique based on the monitoring and recording of the changes in weight of a sample as it undergoes controlled thermal degradation, with varying temperature or time.

Question 27

state 3 advantages of SIMS vs EXPS for surface analysis

Answer 27

1. high sensitivity 2. more sensative to top surface 3. aplicable to any solid

Question 28

what is contact angle measurement?

Answer 28

liquid wetting of surfaces is used to estimate the energy of surfaces

Question 29

what does in-vitro and in-vivo mean

Answer 29

in-vitro: cell cultures in glass in-vivo: animal experiments

Question 30

state 2 techniques for image analysis and describe the information obtained by each of this technique

Answer 30

scanning electron microscopy (SEM): The electrons interact with the atoms that make up the sample producing signals that contain information about the **sample's surface topography, composition, and other properties such as electrical conductivity.**” Transmission Electron Spectroscopy (TEM) Transmission electron microscopy (TEM) is a microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it passes through. An image is formed from the interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen, on a layer of photographic film, or to be detected by a sensor such as a CCD camera.

Question 31

what is GPC and what information does it provide?

Answer 31

gel permeation chromatography an extremely powerful method for determining molecular weight distrubution of a polymer

Question 32

what is XRD and what information does this technique provide

Answer 32

x-ray difraction X-Rays to Determine Crystal Structure