TLS Online TPP Program

#Question id: 10349


Elevated plastid levels of glutamine stimulate the activity of glutamate synthase (also known as glutamine:2- oxoglutarate aminotransferase, or GOGAT). Given below some of the statements about GOGAT, which one of the following is incorrect?

#Unit 6. System Physiology – Plant
  1. Plants contain two types of GOGAT; one accepts electrons from NADH, and the other accepts electrons from ferredoxin (Fd)
  2. The NADH type of the enzyme (NADH-GOGAT) is located in plastids of nonphotosynthetic tissues such as roots or the vascular bundles of developing leaves
  3. The ferredoxin-dependent type of glutamate synthase (Fd-GOGAT) is found in chloroplasts and serves in photorespiratory nitrogen metabolism
  4. This enzyme transfers the amide group of glutamate to 2-oxoglutarate, yielding two molecules of glutamine
More Questions
TLS Online TPP Program

#Question id: 13122

#Unit 2. Cellular Organization

Choose the incorrect?
1- COPI vesicles transport proteins from the rough ER to the cis -Golgi; COPII vesicles transport proteins in the reverse s Direction.
2- The KDEL receptor binds more tightly to its ligand ar low pH, and it is thought that the receptor is able to bind KDEL peptides in the cis-Golgi but to release these peptides in the ER because the pH of the Golgi is slightly lower than that of the ER.
3- The KDEL sorting signal is recognized and bound by the KDEL receptor, a transmembrane protein found primarily on small transport vesicles shuttling between the ER and the cis -Golgi and on the cis-Golgi reticulum.

TLS Online TPP Program

#Question id: 13121

#Unit 2. Cellular Organization

--------- act as a nuclear export factor and directs the associated mRNP to the central channel of the NPC by transiently interacting with FG- nucleoporins.

TLS Online TPP Program

#Question id: 13120

#Unit 2. Cellular Organization

Match the correct one?

Target organelle

 

Location of sequence within protein

 

Removal of sequence

 

Nature of sequence

 

1- ER

 

i- N- terminal

 

a- yes

P- Core of 6-12 hydrophobic aa often preceded by one or

more basic ammo acids (Arg, Lys)

 

2-Mtochrondria matrix

 

ii- N- terminal

b- yes

Q- Multiple different kinds;  rich in Lys and Arg

residues

3-Chloroplast stroma

 

iii- N- terminal

c- no

R- Lys and arg one side and other side hydrophobic aa

4-Nucleus

 

iv-varies

d- yes

S- Generally rich in ser and thr, poor in glu and asp


TLS Online TPP Program

#Question id: 13119

#Unit 2. Cellular Organization

Ions, small metabolites, and globular proteins up to about ---------- can diffuse passively through the central aqueous region of the nuclear pore complex.

TLS Online TPP Program

#Question id: 2059

#Unit 2. Cellular Organization

For a protein to be an integral membrane protein, it would have to be:

TLS Online TPP Program

#Question id: 2060

#Unit 2. Cellular Organization

An animal cell lacking carbohydrates on the external surface of its plasma membrane would likely be impaired in which function?