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TLS Online TPP Program

#Question id: 12836

The final layer of control that is critical in the regulation of CDKs is a family of proteins known as CDK inhibitors, or CKIs, which bind directly to the cyclin-CDK complex and inhibit its activity. Which of the following function not done by CKIs?

#Unit 2. Cellular Organization
  1. Binding of INK4s to CDK4 and CDK6 blocks their interaction with cyclin D and hence their protein kinase activity. 
  2. p27 prevents the premature activation of S phase CDKs during G1.
  3. p21CIP plays an important role in the response of metazoan cells to DNA damage by inhibiting G1/S phase CDKs and S phase CDKs, and thereby blocking entry into or passage through S phase.
  4. During ongoing DNA replication and in response to replication stress (slow DNA replication fork movement or DNA replication fork collapse), the ATR-Chk1 protein kinase cascade phosphorylates and inactivates Cdc25C, thereby preventing the activation of mitotic CDKs and inhibiting entry into mitosis.
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TLS Online TPP Program

#Question id: 10225

#Unit 6. System Physiology – Plant

Air circulation around the leaf removes heat from the leaf surfaces if the temperature of the leaf is higher than that of the air; this phenomenon is called
TLS Online TPP Program

#Question id: 10250

#Unit 6. System Physiology – Plant

Glycolysis involves a series of reactions catalyzed by enzymes located in,
TLS Online TPP Program

#Question id: 10196

#Unit 6. System Physiology – Plant

Why are light compensation points lower for shade plants?
TLS Online TPP Program

#Question id: 10228

#Unit 6. System Physiology – Plant

Photorespiration and the quantum yield differ between C3 and C4 photosynthesis, with changes particularly noticeable as temperatures vary quantum yield for photosynthesis as a function of leaf temperature in C3 plants and C4 plants. Following are some statements  based on this study.

 a.) In the C4 plants the quantum yield remains constant with temperature, reflecting low rates of photorespiration

 b.) At lower temperatures the quantum yield of C3 plants is higher than that of C4 plants

c.) C3 photosynthesis is more efficient at lower temperatures

 d.) At higher temperatures the quantum yield of C3 plants is higher  than that of C4 plants

 Which one of the following combination of above statements is correct?
TLS Online TPP Program

#Question id: 10226

#Unit 6. System Physiology – Plant

Under moderate excess light Quantum efficiency decreases , but the maximum photosynthetic rate remains unchanged and caused by the diversion of absorbed light energy toward heat dissipation—hence the decrease in quantum efficiency this term is known as
TLS Online TPP Program

#Question id: 10223

#Unit 6. System Physiology – Plant

when plastoquinone is accumulates in the reduced state, Reduced plastoquinone accumulates when PSII is being activated more frequently than PSI. What will happen when plastoquinone becomes more oxidized?