The following statements are made to describe the biosynthetic pathway of IAA;

a)  IPA pathway involves a deamination reaction to form IPA, followed by a decarboxylation reaction to form indole-3-acetaldehyde (IAld) and then oxidized to IAA by a specific dehydrogenase

b) IAN pathway is similar to the IPA pathway, except that the order of the deamination and decarboxylation reactions is reversed, and different enzymes are involved

c) IAM pathway  involves the two enzymes  tryptophan monooxygenase and IAM hydrolase

d) In the IAN pathway, tryptophan is first converted to indole-3-acetaldoxime and then to indole-3-acetonitrile. The enzyme that converts IAN to IAA is called nitrilase

Which of the following is the correct  statements  of about the biosynthesis of  IAA?

#Question id: 2425

#Unit 2. Cellular Organization

Which of the following is (are) actin-based structures?

a. adherins belt                        b. contractile ring        c. mitotic spindle

d. nuclear lamina         e. stress fibers

#Question id: 2426

#Unit 2. Cellular Organization

Actin assembly in vitro

a. consists of three phases.     

b. requires addition of actin oligomers termed nuclei.

c. requires ATP hydrolysis.

d. is reversible.

e. requires actin-binding proteins.

#Question id: 2427

#Unit 2. Cellular Organization

Known functions of actin-binding proteins include

a. severing of long filaments to generate shorter filaments.

b. inhibition of filament polymerization.                   

c. bundling of filaments.

d. acceleration of filament polymerization rates.

e. capping of the (+) end.

#Question id: 2428

#Unit 2. Cellular Organization

Which of the following prevent(s) acting disassembly?

a. cytochalasin D         b. jasplakinolide          c. latrunculin               d. phalloidin

#Question id: 2429

#Unit 2. Cellular Organization

Which of the following statements is (are) true of actin assembly?

a. ADP-actin can assemble into filaments.    

b. Actin (+) ends grow faster than actin (-) ends.

c. ATP-actin can assemble into filaments.

d. Toxins that alter the assembly of actin filaments have been used as tools to study actin in living cells.

#Question id: 2430

#Unit 2. Cellular Organization

Actin-binding proteins that generate actin filament bundles: