Cellular senescence may have evolved to protect organisms against cancer. Instead of dividing out of control, the cells die. Cellular senescence appears to be regulated by several tumor suppressor genes, especially p53.what is the most appropriate reason behind this,

1) Transcription factor p53 is thought to suppress tumorigenesis by causing cell arrest and senescence in response to short telomeres, DNA damage, and viral or external signals to divide

2) This factor can stop the cell cycle, cause cellular senescence in rapidly dividing cells, instruct genes to initiate cellular apoptosis, and activate DNA repair enzymes.

3) Induction of apoptosis or cellular senescence by p53 always beneficial.

#Question id: 454

#Unit 1. Molecules and their Interaction Relevant to Biology

Which statement is false about most metabolic pathways?

#Question id: 455

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following is correct for a step in a reaction pathway to serve as a control point

A) irreversible  B) endergonic  C) far from equilibrium

#Question id: 456

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following function is done by compartmentation of enzymes?

A) helps loss by diffusion.

B) keeps separate pools of metabolites in cells.

C) can help control metabolic pathways.

#Question id: 457

#Unit 1. Molecules and their Interaction Relevant to Biology

Which are membrane associated pathways?

A) electron transport chain in eukaryotes

B) citric acid cycle in bacteria

C) photosynthesis

D) glycolysis

#Question id: 458

#Unit 1. Molecules and their Interaction Relevant to Biology

Ten people are sitting in a row. Their objective is to whisper a secret from one person to the next all the way down the row. The first person whispers the secret to the second person who passes the secret to the third person and so on. After whispering to the third person, the second person in the row notices the ninth person has fallen asleep in their chair, so she gets up, goes down the row and shakes person nine awake. This example is similar to ________.

#Question id: 459

#Unit 1. Molecules and their Interaction Relevant to Biology

Calculate △G°ʹ for the reaction shown if the mass action ratio, Q, is 5.3 × 102 M-1 and △G is 46 kJ/mol at a temperature of 298 K. (R = 8.315 J/K-mol)

ADP + Pi ⇌ ATP