You have isolated a set of five yeast mutants that form dark red colonies instead of the usual white colonies of wild-type yeast. You cross each of the mutants to a wild-type haploid strain and obtain the results shown below;

you cross each haploid mutant strain to a different haploid mutant of the opposite mating type. From the results shown below deduce as much as you can about which mutations lie in the same gene. Clearly state any remaining ambiguities and suggest some general ways that the ambiguities might be resolved

a) That mutants 1 and 3 form one complementation group and are mutations in the same gene (gene A) 

b) That mutations 2 and 5 form a second complementation group and are mutations in a second gene (gene B).

c) That mutations 3 and 5 form a second complementation group and are mutations in a second gene (gene B).

d) The first ambiguity is whether mutant 4 has a mutation in gene A or B, or whether it represents a unique gene.

Which of the following is the correct prediction about mutants?

#Question id: 2440

#Unit 2. Cellular Organization

Microtubule assembly in vitro requires

a. ATP.                                                           

b. a threshold (critical) concentration of tubulin.

c. warming the solution to 37°C.                   

d. microtubule-associated proteins.         

e. GTP.

#Question id: 2441

#Unit 2. Cellular Organization

Which of the following statement(s) is (are) true of microtubule assembly?

a. GDP-tubulin normally assembles into microtubules.

b. Microtubule (-) ends grow faster than microtubule (+) ends.

c. Tubulin subunits assemble to form a protofilament.

d. Microtubules consist of multiple protofilaments.

e. Microtubules with a GTP cap will shorten.

#Question id: 2442

#Unit 2. Cellular Organization

The drug colchicine acts to

a. promote microtubule assembly.     

b. inhibit microtubule assembly.

c. sever microtubules.                        

d. block cell division.

e. cap microtubule ends.

#Question id: 2443

#Unit 2. Cellular Organization

Microtubule-associated proteins

a. typically co-localize with microtubules inside cells.

b. are divided into two types: those that stabilize microtubules and those that destabilize microtubules.

c. typically co-purify with microtubules.                  

d. are similar to α- and β-tubulin.

#Question id: 2444

#Unit 2. Cellular Organization

Kinesin I moves vesicles

#Question id: 2445

#Unit 2. Cellular Organization

All members of the kinesin family of motor proteins