Question

1)Which metal center is responsible for oxidation of water within photosystem II?

2) Which metal ion is bound in a molecule of plastocyanin?

3) Guanosine-capping and methylation events occur at 3’-end of mRNA during the transcription in yeast. TRUE OR FALSE? 4)The operator sequence can be overlapped with the promoter sequence in prokaryotes. TURE OR FALSE?

5) Yeast RNA polymerase recognize the TATA box binding protein at the promoter sequence. TRUE OR FALSE?

6)There are three DNA polymerases in prokaryotes. All of them have 5’à3’ polymerase activity. However, only one of them has 5’à3’ exonuclease activity to digest the primer part of __________________ fragments for the legging strand synthesis. FILL IN THE GAP PLEASE.

Answer 1

1. Manganese metal center is responsible for the oxidation of water with in the photosystem - II.

This metal center composed of metallo oxo-cluster comprising of four manganese ions and one divalent calcium ion. It oxidizes water by producing oxygen gas and protons. So this metal center also called as oxygen evolving complex.

2. Plstocuanin is a copper containing protein. It is found in all photosynthetic plants. The main function of plastocyanin is electron transporter during photosynthesis.

3. False.

Guanosine cap is added at the 5' end of the nescent MRNA.

4. True.

Example: lac operon gene regulation.

5. True. Yeast RNA polymerase recognize the TATA box binding protein.

6. There are three DNA polymerases in prokaryotes. All of them have 5’à3 polymerase activity, however only one of them have 5’à3 exonuclease activity to digest the primer part of okazaki fragments for the legging strand synthesis.