Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 2953
TLS Online TPP Program

#Question id: 2978

The most important regulatory control that restricts cyclins to the appropriate cell cycle stage is ubiquitin mediated, proteasome-dependent protein degradation. Which of the following statement is incorrect regarding to the degradation of protein?

#Unit 2. Cellular Organization

  1. SCF and APC/C are multisubunit ubiquitin-protein ligases that belong to the RING finger family of ubiquitin protein ligases which ensure that the cell cycle engine is driven forward and that cells cannot “go backward” in the cell cycle.

  2. SCF recognizes its substrates only when they are phosphorylated.

  3. The substrate specificity of active, dephosphorylated APC/C is determined in part by its association with one of two related substrate targeting factors called Cdc20 and Cdh1.

  4. The substrates of APC/C contain recognition motifs known as destruction box which is lysine rich.

More Questions
TLS Online TPP Program

#Question id: 10411

#Unit 6. System Physiology – Plant

Phytochrome chromophore which absorbs light known as Phytochromobilin , that are synthesized in
TLS Online TPP Program

#Question id: 10412

#Unit 6. System Physiology – Plant

Red and far-red lights are perceived by plants through various photoreceptors including phytochromes. The red/far-red reversibility of seed germination was due to the-
a) photoreversibility of phytochrome
b) presence of red and far-red light at different fluence rate
c) Conversion of Pr to Pfr form through the effect of red light
d) equal proportion of red and far red light at same fluence rate
Which of the following combinations is correct?
TLS Online TPP Program

#Question id: 10413

#Unit 6. System Physiology – Plant

Following are certain statements are related to the effect of red and far-red light;
a) under a dense canopy much of the red light is absorbed by plant pigments, resulting in transmittance of mostly far-red light
b) Pr (red) has highest photon flux at 680 nm while Pfr (far-red) has highest photon flux at 730nm
c) Pfr far-red light–absorbing form, which is considered to be the physiologically active form of phytochrome
d) R:FR ratio is strongly affected by the presence of a canopy because chlorophyll absorbs far-red but not red light
Which one of the combinations of above statements is incorrect?
TLS Online TPP Program

#Question id: 10414

#Unit 6. System Physiology – Plant

Plants have evolved with multiple photoreceptors, Phytochrome is one of them. Which of the following statements is incorrect about these photoreceptors?
TLS Online TPP Program

#Question id: 10415

#Unit 6. System Physiology – Plant

Bacterial phytochromes are light-dependent kinases Which of the following classes of kinases does it represent?
TLS Online TPP Program

#Question id: 10416

#Unit 6. System Physiology – Plant

Phytochromes  involved  in  red/far‐red  response  are  dimeric  chromoproteins contains N-terminal and C-terminal moiety have domains, which perform various functions such as;
a) Photochromobillin attach with the N-terminal GAF domain, it is an enzyme which causes isomerisation activity in the phytochromobilin
b) PAS-GAF-PHY is a photosensory domain
c) PAS domain perform the lyase activity at C-14 and C-15, which creates a double bond
d) PRD is PAS related domain which involve in import of Phy-B in the nucleus
Which of the following combinations of domain functions is incorrect?