Species-specific sperm attraction has been documented in numerous species. In echinoderms, sperm are attracted toward eggs of their species by chemotaxis. Following statements are about chemoattraction-

A. In this process Sperm follows a gradient of a chemical secreted by the egg.

B. These oocytes control only the type of sperm they attract, but not the time at which they attract them.

C. Releasing the chemotactic factor only when the sea urchin egg has completed all of its meiotic divisions .

D. Releasing the chemotactic factor only when the sea urchin egg is in second metaphase of its meiotic division.

E. The mechanisms of chemotaxis differ among species and chemotactic molecules are different even in closely related species.

Which of the following statement are incorrect about this process?

TLS Online TPP Program

#Question id: 26498

#Unit 3. Fundamental Processes

Which of the following shows correct bond pattern in Lactose and Allolactose

TLS Online TPP Program

#Question id: 26497

#Unit 3. Fundamental Processes

There are three type of Splicing signals 1. Major U2-type or GU-AG introns 2. Minor U12-type or AU-AC introns & 3. Minor U12-type with GU-AG introns (hybrid type), which of the following is responsible for the recognition of branch point sequence UACUAAC?

TLS Online TPP Program

#Question id: 26496

#Unit 3. Fundamental Processes

Two transesterification reactions takes place for 2 exon -1 intron configuration. Choose the correct  statement

a. First transesterification is always caused by exon 1 -3’OH

b. second transesterification is catalysed variably either by external G or branch point while .

c. First transesterification is catalysed variably either by external G or branch point while 

d. second transesterification is always caused by exon 1 -3’OH.

TLS Online TPP Program

#Question id: 26495

#Unit 3. Fundamental Processes

Which of the following is (are) required for splicing to occur?

a. two transesterification reactions

b. intact, naturally occurring introns

c. formation of a lariat like structure 

d. a branch-point G residue

TLS Online TPP Program

#Question id: 26494

#Unit 3. Fundamental Processes

Class and abundance is given Match them correctly

TLS Online TPP Program

#Question id: 26490

#Unit 3. Fundamental Processes

Choose which of the following factors are involved in the Regeneration of CTD tail