Following statements are regarding to multiple signaling pathways in vertebrate cells that regulate outer mitochondrial membrane permeability and apoptosis.

A. In healthy cells, the anti-apoptotic protein Bcl-2, or its homolog Bcl-xL, binds to Bak or Bax pro-apoptotic proteins, blocking the ability of Bak or Bax to oligomerize and form pores in the outer mitochondrial membrane.

B. The presence of specific trophic factors (e.g., NGF) leads to activation of their cognate receptor tyrosine kinases (e.g., TrkA) and inactivation of the PI-3 kinase–PKB (protein kinase B) pathway.

C. PKB phosphorylates Bad, and phosphorylated Bad forms a complex with a cytosolic 14-3-3 protein. This sequestered Bad is unable to bind to Bcl-2.

D. In the absence of trophic factors, nonphosphorylated Bad binds to Bcl-2, releasing Bax and Bak and allowing them to form oligomeric membrane pores and holes.

E. DNA damage or ultraviolet irradiation leads to induction of synthesis of the BH3-only Puma protein. Puma binds to Bak and Bax as well as to Bcl-2, allowing Bak and Bax to form oligomeric pores.

F. Removal of a cell from its substratum disrupts integrin signaling, leading to release of the BH3-only Bim protein from the cytoskeleton. Bim also binds to Bak and Bax to promote pore formation.

Which of the following is incorrect?

#Question id: 997

#Unit 1. Molecules and their Interaction Relevant to Biology

Complete oxidation of 1 mole of which fatty acid would yield the most ATP?

#Question id: 998

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following statements apply (applies) to the B oxidation of fatty acids?

1.  The process takes place in the cytosol of mammalian cells.

2.  Carbon atoms are removed from the acyl chain one at a time.

3.  Before oxidation, fatty acids must be converted to their CoA derivatives.

4.  NADP+ is the electron acceptor.

5.  The products of B oxidation can directly enter the citric acid cycle for further oxidation.

#Question id: 999

#Unit 1. Molecules and their Interaction Relevant to Biology

The balanced equation for the degradation of CH3(CH2)10COOH via the B-oxidation pathway is:

#Question id: 1000

#Unit 1. Molecules and their Interaction Relevant to Biology

 Which of the following is (are) true of the B oxidation of long-chain fatty acids?

1. The enzyme complex that catalyzes the reaction contains biotin.

2. FADH2 serves as an electron carrier.

3. NADH serves as an electron carrier.

4. Oxidation of an 18-carbon fatty acid produces six molecules of propionyl-CoA.

5. Oxidation of a 15-carbon fatty acid produces at least one propionyl-CoA.

#Question id: 1001

#Unit 1. Molecules and their Interaction Relevant to Biology

The following fatty acid, in which the indicated carbon is labeled with ¹⁴C, is fed to an animal:  ¹⁴CH₃(CH₂)₉COOH After allowing 30 minutes for fatty acid B oxidation, the label would most likely be recovered in:

#Question id: 1002

#Unit 1. Molecules and their Interaction Relevant to Biology

What would be the product of the transamination of the structure shown below? (The unionized forms are shown.)