Tissue Architecture

Question 1

Which of the following correctly describes intermediate filaments?

A. Locomotion

B. Resistant to stretching forces

C. Forms mesh like structure called nuclear lamina

D. Part of cilia and flagella

E. A and D

F. B and C

Answer 1

F B. Resistant to stretching forces C. Forms mesh like structure called nuclear lamina

Question 2

Progeria is a disease that affects ___________ a type of __________ cytoskeleton filament, so that the body appears to rapidly age.

Answer 2

Progeria is a disease that affects ___nuclear lamina____ causing the ______intermediate_______ cytoskeleton filament, so that the body appears to rapidly age.

Question 3

Which of the following intermediate filaments are found in connective tissue cells, muscle cells, and glial cells?

A. Keratin Filaments

B. Vimentin

C. Neurofilaments

D. Nuclear lamins

Answer 3

Vimentin

Question 4

All of the following are drugs that are specific to microtubules. All except one binds tubulin dimers and prevents their polymerization, except which? What does it do instead?

A. Taxol

B. Colchine and colcemid

C. Vinblastine and Vinecristine

D. None of the above

Answer 4

Taxol - binds and stabilizes microtubules

Question 5

Which of the following actin specific drugs binds and stabilizes filaments?

A. Cytochalisin

B. Latrunculin

C. Phalloidin

D. All of the above

Answer 5

Phalloidin

Question 6

Which of the following actin specific drugs binds the plus end of the filament in order to prevent polymerization?

A. Cytochalisin

B. Latrunculin

C. Phalloidin

D. All of the above

Answer 6

Cytochalisin

Question 7

Which of the following actin specific drugs binds actin monomers and prevents their polymerization?

A. Cytochalisin

B. Latrunculin

C. Phalloidin

D. All of the above

Answer 7

Latrunculin

Question 8

Nidogen/enactin are a subset of which of the following extracellular matrix proteins?

A. Proteoglycans

B. Collagens

C. Multi-adhesive matrix proteins

D. None of the above

Answer 8

Multi-adhesive matrix proteins - Nidogen/enactin - Laminin - Fibronectin NOTE: Perlecan is a type of proteoglycan

Question 9

All of the following are fibrillar collagens EXCEPT which?

A. Type I

B. Type II

C. Type III

D. Type IV

Answer 9

Type IV - sheet-forming collagen

Question 10

Which of the follwoing is the main structural protein in the ECM?

A. Proteoglycans

B. Collagens

C. Multi-adhesive matrix proteins

D. None of the above

Answer 10

Collagens

Question 11

Below are the following steps of collagen synthesis. 1. Synthesis of preprocollagen –> insertion into ER lumen 2. Hydroxylation of proline and lysine and glycosylation of hydroxylysine residues 3. Self-assembly of the tropocollagen molecule and triple helic formation in ER and golgi 4. Procollagen prepared for secretion from cell and secreted via vesicles 5. Cleavage of propeptides and self assembly of collagen molecules into fibrils then fibers outside in the extracell state

Answer 11

1. Synthesis of preprocollagen –> insertion into ER lumen 2. Hydroxylation of proline and lysine and glycosylation of hydroxylysine residues 3. Self-assembly of the tropocollagen molecule and triple helic formation in ER and golgi 4. Procollagen prepared for secretion from cell and secreted via vesicles 5. Cleavage of propeptides and self assembly of collagen molecules into fibrils then fibers outside in the extracell state

Question 12

Scurvy is a loss of what 2 cofactors that prevents the enzyme prolyl hydroxylase to convert 2-oxoglutarate into CO2 and succinate?

Answer 12

Iron

Ascorbate

Question 13

Which of the following link cells to extracellular matrix or basal lamina?

A. Cell junctions

B. Focal contacts

Answer 13

Focal contacts

Question 14

All of the following are examples of Classical Cadherins except for which of the followin that are examples of Atypical Cadherins? (select All that apply)

A. E-cadherin

B. T-cadherin

C. N-cadherin

D. R-cadherin

E. VE-cadherin

F. LI-cadherin

Answer 14

T-cadherin

LI-cadherin

Question 15

Which of the following correctly describes Atypical Cadherins and not Classical cadherins?

A. Well established Calcium dependent adhesion function

B. Cytoplasmic domains interact with Beta-catenin, alpha-catenin, and p120

C. Associated with adherens junctions

D. Function as homophilic adhesion proteins without interaction with catenins or link to actin cytoskeleton

Answer 15

Function as homophilic adhesion proteins without interaction with catenins or link to actin cytoskeleton

Question 16

Which of the following is most likely to be seen in metastatic tumors with increased invasiveness? (select all that apply)

A. Increase in E-cadherin and N-cadherins

B. Decrease in E-cadherin and N-cadherins

C. Decrease in E-cadherin and Increase in N-cadherins

D. Epithelial Mesenchymal Transition

Answer 16

Epithelial Mesenchymal Transition

Decrease in E-cadherin and Increase in N-cadherins