Lysozyme is an enzyme that destroys bacterial cell walls. It does so by hydrolyzing the β(1→4) glycosidic linkages from N- acetylmuramic acid (NAM or MurNAc) to N- acetylglucosamine (NAG or GlcNAc) in cell wall peptidoglycans. The only functional groups in the immediate vicinity of lysozyme’s reactive center that have the required catalytic properties are the side chains of Glu 35 and Asp 52.

a- Glu perform reaction in its protonated state and Asp perform reaction in its deprotonated state. 

b- Glu perform reaction in its deprotonated state and Asp perform reaction in its protonated state. 

c- both in its protonated form

d- both in its deprotonated form 

Choose the correct option?

#Question id: 10151

#Unit 6. System Physiology – Plant

Light regulates the stability of the ternary complex through the ferredoxin–thioredoxin system Regulation of chloroplast phosphoribulokinase and glyceraldehyde-3-phosphate dehydrogenase. Chloroplasts contain two isoforms of glyceraldehyde3-phosphate dehydrogenases, named A4 and A2B2. Which of the following statement about isoform of glyceraldehyde3-phosphate dehydrogenases is False?

#Question id: 10138

#Unit 6. System Physiology – Plant

The Calvin–Benson cycle proceeds in three phases that are highly coordinated in the chloroplast these three phases namely--Carboxylation, Reduction and Regeneration. The following statements are not related to the three phases of Calvin–Benson cycle:

#Question id: 10136

#Unit 6. System Physiology – Plant

A protein complex contain a Rieske protein known as

#Question id: 10134

#Unit 6. System Physiology – Plant

Some herbicides such as dichlorophenyldimethylurea (DCMU, also known as diuron) and paraquat, block photosynthetic electron flow from where ?

a.) DCMU blocks electron flow at the quinone acceptors of PSII, by competing for the binding site of plastoquinone that is normally occupied by PQB

b.) Paraquat accepts electrons from the early acceptors of PSI and then reacts with oxygen to form superoxide, O2 – , a species that is very damaging to chloroplast components

c.) DCMU blocks electron flow at the pheophytin acceptors of PSII, by competing for the binding site of pheophytin

d.) Paraquat accepts electrons from the Iron-sulfur system of PSI and then reacts with oxygen to form superoxide, O2 – , a species that is very damaging to chloroplast components

Which of the following combination is true?

#Question id: 10133

#Unit 6. System Physiology – Plant

The PSI reaction center complex is a large multi-subunit complex in which the antenna chlorophylls are associated with the reaction center Components of the PSI reaction center are organized around as follows choose the incorrect one;

#Question id: 10132

#Unit 6. System Physiology – Plant

Which of the following statements would be correct for photophosphorylation ?